A wide variety of mammographic findings are seen after surgical procedures on the breast. Surgical procedures—including core needle biopsy, excisional breast biopsy, wide excision or segmental mastectomy, subcutaneous or modified radical mastectomy with reconstruction, reduction mammoplasty, and lumpectomy with radiation therapy—produce a spectrum of classical and unusual findings. Critical to an accurate analysis of a mammogram and to determination that findings are of postsurgical origin is knowledge of the history and clinical examination of the patient.
It is of help to place a wire or BB marker on the skin to avoid repeating films because of uncertainty about positions of scars. If this is not done, then it is absolutely necessary that the technologist be responsible for clearly marking the location and orientation of any scars on a drawing of the breast. The surgical site is sometimes demarcated with surgical clips, particularly in cases of lumpectomy performed for carcinoma. Additionally, it is equally important to document the location and size of any palpable masses and particularly their relationship to the surgical scar.
In interpreting a mammogram of a postsurgical breast, it is important for the radiologist to compare present studies with previous studies. Temporal changes are reflective of the normal evolution of postsurgical findings. Also, knowledge of the appearance of the original lesion in patients who have undergone lumpectomy and correlation with the specimen film is helpful to identify residual disease.
Immediately after a needle biopsy of a breast lesion, there may be a small amount of air at the biopsy site, especially when a vacuum-assisted biopsy is performed. Occasionally, there also may be irregular increased density at the site from edema and hematoma formation. Unless there is significant bleeding during the biopsy, the changes are subtle. If there is a puncture of a vessel during a needle biopsy, a hematoma may form. If the hematoma dissects through the tissue, an amorphous ill-defined density is seen on mammography. If a hematoma is more localized, then the appearance is that of a relatively circumscribed mass (Fig. 12.1). These findings are typically observed immediately after the biopsy on the postprocedure mammogram. In most cases, however, there is no long-term mammographic finding after a needle biopsy.
The mammographic findings associated with excisional biopsy are localized to the area of the biopsy site. It is, therefore, important to correlate the position of the scar to the mammographic findings and to be aware of the temporal changes that are expected postsurgically. In a study of 1,049 breast biopsies, Sickles and Herzog (1) found mammographic abnormalities attributed to postsurgical changes in 474 (45%). Normal postsurgical changes include localized skin thickening or retraction, an asymmetric glandular defect, architectural distortion, contour deformity of the breast, hematoma or seroma, fat necrosis formation, parenchymal scarring (Figs. 12.2,12.3,12.4,12.5,12.6), calcifications of fibrosis (Figs. 12.7 and 12.8), fat necrosis and sutures, and opaque foreign bodies (1,2) (Figs. 12.9,12.10,12.11).
Skin thickening is localized to the biopsy site unless there is superimposed infection, in which case a more generalized thickening is present. A contour deformity may be associated with the skin thickening. Skin thickening is maximum on mammography during the first 6 months after biopsy and gradually diminishes. In a majority of patients who have undergone a lumpectomy or excisional biopsy for benign disease, the focal skin thickening is nearly inapparent on mammography after several years.
A hematoma may be seen at the biopsy site on a mammogram performed soon after biopsy. Postoperative hematoma or seromas are seen more commonly if a drain has not been placed and may actually be related to an improved cosmetic result with a lesser degree of contour
deformity (3). On mammography, fluid collections are usually relatively circumscribed medium- to high-density masses and may range from 2 to 10 cm in diameter. In a series of postlumpectomy patients who were referred for radiotherapy, Mendelson (3) found postoperative fluid collections in 47%. On ultrasound, hematomas or seromas are relatively smooth and anechoic but may contain some internal echoes or debris, depending on the degree of organization (4). Because fluid collections may contain debris even if they are not infected, the clinical findings are of more help to suggest the presence of superimposed infection.
Figure 12.1 HISTORY: A 45-year-old woman for biopsy of multiple left breast lesions.
MAMMOGRAPHY: Left CC view (A) immediately after needle biopsy and left CC (B) and ML (C) views 2 hours later. A spiculated mass is present centrally (white arrow), and an indistinct mass is located medially (arrow), both of which were biopsied. There are also faint, pleomorphic microcalcifications laterally that were biopsied. Following vacuum-assisted core needle biopsies, the medial area was associated with the interval development of a lobulated circumscribed mass, consistent with a hematoma.
IMPRESSION: Hematoma following core needle biopsy of suspicious left breast lesion, multiple left breast lesions suspicious for carcinoma.
HISTOPATHOLOGY: Invasive ductal carcinoma, multicentric.
NOTE: The medial round mass represented a small hematoma secondary to core biopsy.
Figure 12.2 HISTORY: Routine mammography following surgical excision for left breast microcalcifications that were benign.
MAMMOGRAPHY: Left MLO (A) and left MLO (B) 1 year later, following surgical excision. There is dense parenchyma with some fine punctuate and amorphous microcalcifications in a regional distribution (A). These were removed by surgical excision following needle localization.
IMPRESSION: Contour defect following surgical excision or lumpectomy.
Areas of architectural disturbance are a common finding after surgery and include asymmetric decrease in glandular tissue from resection that does not change over time (1), architectural distortion, and focal increased density or parenchymal scar and fat necrosis. As a hematoma resolves, it is usual to see some residual, irregular increased density and/or distortion. Architectural distortion was the second most common postsurgical finding after skin thickening by Sickles and Herzog (1) in the evaluation of 474 postoperative breasts.
The changes of increased density and architectural distortion are maximum at 0 to 6 months after surgery and gradually diminish over time (1). The presence of entrapped fat within the distortion is also suggestive of scar. Scars also tend to have a different shape on two views, appearing as a spiculated area of architectural distortion on one view and as much less distorted on the orthogonal view. Often the extension of the distortion to the skin scar is also noted.
Figure 12.3 HISTORY: A 48-year-old gravida 2, para 2 woman 6 months after left breast biopsy, presenting with no new palpable findings.
MAMMOGRAPHY: Left CC view from a needle localization (A) and left CC view (B) and ultrasound (C) 6 months after biopsy. On the initial film (A), a needle localization wire is marking a cluster of microcalcifications (arrow) for biopsy. The histopathology was benign. On the subsequent study (B), there is a large, high-density, partially circumscribed mass at the biopsy site. On ultrasound (C), the mass is complex, appearing circumscribed with some acoustic enhancement. The features are typical of a postoperative hematoma or seroma, and a fluid collection of this size may not be palpable. The patient was followed without aspiration of the seroma.
IMPRESSION: Large postoperative hematoma or seroma.
Figure 12.4 HISTORY: A 51-year-old woman status post–benign right breast biopsy.
MAMMOGRAPHY: Right MLO (A) and CC (B) views show an essentially fatty-replaced breast. The postsurgical site is indicated by a wire marker. This appears dense and spiculated on the CC view but is more amorphous and vertically oriented on the MLO view. The differing appearance on the two projections is typical of a scar.
IMPRESSION: Postsurgical scar.
Figure 12.5 HISTORY: A 72-year-old gravida 2, para 2 woman for follow-up 1 year after a right breast biopsy that showed fibrocystic change.
MAMMOGRAPHY: Bilateral MLO (A) and CC (B) views. There is an irregular density in the right upper-outer quadrant (arrows). On the MLO view (A), the lesion appears somewhat less dense and spiculated than on the CC view (B). The difference in shape of such a density suggests more likely a benign rather than a malignant etiology. This density was confirmed to be in the location of the scar from the previous biopsy.
IMPRESSION: Irregular density consistent with fat necrosis and scar after excisional biopsy.
Figure 12.6 HISTORY: A 55-year-old gravida 0 woman for follow-up mammography after a benign biopsy in the right breast.
MAMMOGRAPHY: Right MLO film (preoperative) (A), right MLO (B) and CC (C) view 6 months after biopsy, and right MLO (D) and CC (E) views 12 months after biopsy. The preoperative film (A) demonstrates a small cluster (arrow) of microcalcifications that were biopsied and found to be benign. On the initial postoperative study (B and C), there is a 3-cm ill-defined area of increased density in the right middle-outer quadrant. On the CC view (C), the area is of lower density than would be expected for a neoplastic process. Because the location of the biopsy was in this area, the density is most consistent with scar and fat necrosis. Six months later (D andE), the area of that fat necrosis has decreased in size, as would be expected for normal postoperative changes.
IMPRESSION: Postoperative fat necrosis and scar, decreasing in size.
Figure 12.7 HISTORY: A 32-year-old gravida 0 woman who had had breast reduction 3 years ago, presenting with a firm irregular nodule in the right lower-inner quadrant.
MAMMOGRAPHY: Bilateral MLO (A), CC (B), and enlarged (2÷) right CC (C) views. The breasts show fatty replacement. In the right lower-inner quadrant, there is an irregular area of increased density associated with a radiolucent mass containing eggshell calcification in the wall (curved arrow). A radiolucent lesion is typical of an oil cyst and is most consistent with posttraumatic changes from reduction mammoplasty. The area was biopsied because of clinical concern about the palpable findings. Incidental note is also made of a small degenerating fibroadenoma in the left middle-inner quadrant (arrow).
IMPRESSION: Fat necrosis, oil cyst.
HISTOPATHOLOGY: Fat necrosis.
Figure 12.8 HISTORY: A 78-year-old gravida 2, para 2 woman after right breast biopsy for microcalcifications that were found to be epithelial hyperplasia, presenting for routine follow-up.
MAMMOGRAPHY: Right enlarged (2÷) CC view (A) 6 months postoperatively and right MLO (B) and enlarged XCCL (C) views 12 months postoperatively. On the initial study (A), there is an irregular area (arrow) of increased density in the outer aspect of the breast. This corresponded in location to the scar and was presumed to represent fat necrosis. Six months later (B and C), the density has resolved and has been replaced by a lucent mass with a calcifying rim (B, arrow), consistent with an oil cyst.
IMPRESSION: Postoperative fat necrosis evolving into an oil cyst.
Figure 12.9 HISTORY: A 52-year-old woman 5 years after treatment for intraductal carcinoma of the left breast with lumpectomy and radiation therapy.
MAMMOGRAPHY: Left MLO view. The breast is moderately dense. Surgical clips have been placed at the lumpectomy site to outline the tumor bed for radiation therapy planning. A single calcification of fat necrosis (arrow) is noted at the tumor bed.
IMPRESSION: Foreign bodies: surgical clips marking tumor bed.
Figure 12.10 HISTORY: A 64-year-old woman status postlumpectomy and radiotherapy for right breast ductal carcinoma.
MAMMOGRAPHY: Right MLO (A) and CC (B) views show marked distortion and skin retraction related to postsurgical scarring. Surgical clips demonstrate the tumor bed, and wires have been placed on the skin to mark the surgical scars. In the medial aspect of the breast is a segment of the hook wire (arrow) used during a prior needle localization. The wire was present for three subsequent years and has not been associated with any side effects.
IMPRESSION: Posttreatment changes, retained segment of localization hook wire.
Figure 12.11 HISTORY: A 24-year-old woman with acute leukemia and neutropenia, presenting with a 2 ×2-cm tender mass in the left upper-inner quadrant. (A BB was placed over the palpable lesion for mammography).
MAMMOGRAPHY: Left MLO view (A) and left enlarged (2÷) CC view (B). There are scattered fibroglandular densities present. Far posteriorly in the upper inner quadrant in the area of palpable mass is a tubular intraparenchymal artifact. Some surrounding increased density is present (A and B). This tubular structure is the tip of a catheter for chemotherapy, which had been removed several months earlier. The tip was severed and remained in the breast and had not been clinically evident until the surrounding inflammation occurred.
IMPRESSION: Catheter tip with surrounding inflammatory changes.
When one is interpreting a spiculated density as a postsurgical change, it is important to review the mammogram before biopsy to confirm that the lesion removed was in fact in the area of concern and, if nonpalpable, was present in the specimen. The most helpful factor that can aid one in making the diagnosis of “postsurgical change” on subsequent studies is a mammogram at 3 to 6 months after biopsy (1). This is particularly important when the biopsy demonstrated an atypical lesion.
Calcifications of fat necrosis form at variable times after biopsy but usually later than 6 months. These calcifications are typically ringlike, with lucent centers, and may be small (liponecrosis macrocystica calcificans) or larger oil cysts (radiolucent masses with eggshell calcifications). Occasionally, fat necrosis may be associated with clumps of irregular but rather coarse microcalcifications. Other forms of calcification that occur postoperatively include ringlike dermal calcifications in the scar, particularly in keloids. Calcified sutures, which are in linear or knot
shapes, are observed postoperatively but more frequently in patients treated with radiotherapy (5).
Foreign bodies left in the breast include surgical clips (often used for marking a tumor bed for location of a boost dose of radiotherapy) and sutures that may calcify. Inadvertent transection of a needle localization wire and lack of its retrieval will result in the observation of a small segment of wire in the breast. Another cause of an iatrogenic foreign body in the breast is the inadvertent severing of the tip or cuff of a central venous catheter for chemotherapy, which may be embedded in the upper inner aspect of the breast (6).
Breast reduction is performed for cosmetic reasons (to treat macromastia) or to achieve symmetry of the contralateral breast after the patient has undergone mastectomy with reconstruction. The surgical procedure involves elevation of the nipple, resection of glandular tissue, and skin removal (7). If there is a nipple transposition procedure, the nipple-areolar complex remains attached to the lactiferous ducts, and the whole complex is transposed upward. In a transplantation procedure, the nipple-areolar complex is severed from the ducts and is transplanted upward (7).
Mammographic findings vary with the type of procedure performed. In patients with a transposition, the subareolar ducts are in a normal relationship with the nipple-areolar complex, but there is a disruption of this orientation after transplantation procedures. Miller et al. (7) found parenchymal redistribution, with most of the fibroglandular tissue below the level of the nipple, as the most common finding in 24 patients who had undergone reduction mammoplasties. Elevation of the nipple was also a common finding, along with thickening of the skin of the lower aspect of the breast and the areola (7). There may be disorientation of the normal parenchymal pattern, with swirled patterns of tissue distribution (8). The scars on the skin may be evident on the mammogram as circumlinear densities traversing the inferior aspect of the breast (Figs. 12.12,12.13,12.14,12.15,12.16,12.17,12.18,12.19).
Figure 12.12 HISTORY: A 55-year-old woman who is status postreduction mammoplasty.
MAMMOGRAPHY: Bilateral MLO (A) and CC (B) views show fatty-replaced breasts. There is mild distortion of the tissue with linear swirling inferiorly (arrows). The breasts have a flattened appearance on the MLO views, and the nipples are located more superiorly than in the normal state. This combination of findings is typical of postsurgical changes from reduction mammoplasty.
IMPRESSION: Postoperative changes secondary to reduction mammoplasty.
Figure 12.13 HISTORY: A 47-year-old woman is status postreduction mammoplasty, for routine screening.
MAMMOGRAPHY: Bilateral MLO (A) and CC (B) views show scattered fibroglandular densities. The breasts have a somewhat flattened appearance on the MLO views, and the nipples are situated higher than in the normal state. There are linear densities (arrows)inferiorly, best seen on a left MLO enlarged image (C); these represent the scar lines related to the reduction procedure.
IMPRESSION: Postoperative changes from reduction mammoplasty.
Figure 12.14 HISTORY: A 54-year-old woman status postreduction mammoplasty, for screening mammography.
MAMMOGRAPHY: On MLO (A) and CC (B) views, the breasts are primarily fatty replaced. There is some distortion of the architecture, with linear structures (arrow) traversing the inferior aspects of the breasts, consistent with postsurgical scars. The nipple areolar complex is located higher than usual. Extensive calcifications are present bilaterally, which on magnification views (C, D) are lucent centered and grouped as well as extending along the scar lines.
IMPRESSION: Postreduction mammoplasty changes with extensive dermal calcifications.
Figure 12.15 HISTORY: A 36-year-old woman who underwent reduction mammoplasties, for routine follow-up.
MAMMOGRAPHY: Baseline preoperative bilateral MLO views (A), MLO (B) and CC (C) views 1 year postoperatively, and enlarged (2÷) right MLO view (D) 2 years postoperatively. On the baseline mammogram (A), the breasts are composed of dense, symmetrical fibroglandular tissue. After reduction (B and C), a large amount of fibroglandular tissue has been removed, and there is disorientation of the remaining tissue and elevation of the nipple, consistent with normal changes after the procedure. This pattern should suggest to one the findings of a reduction procedure, even without knowledge of the clinical history. One year later (D), there has been interval development of multiple oil cysts (arrow) and some smaller coarse calcifications of fat necrosis in the upper outer quadrant.
IMPRESSION: Postreduction changes, with development of fat necrosis. (Case courtesy of
Dr. Cherie Scheer, Richmond, VA.
Figure 12.16 HISTORY: A 44-year-old gravida 3, para 3 woman after left mastectomy and reduction mammoplasty on the right.
MAMMOGRAPHY: Right MLO (A) and CC (B) views. There is distortion of normal architecture with disturbance of the normal orientation of the ducts toward the nipple. In the lower central aspect of the right breast, there is focal irregular increased density (B, arrow)along the direction of the reduction scar (marked by BBs). This finding is typical of the fat necrosis and scarring that is seen after reduction mammoplasty.
IMPRESSION: Postoperative changes after reduction mammoplasty.
Mandrekas et al. (9) described fat necrosis in 1.7% of patients following breast reduction. These patients all presented with a palpable mass that was located deep in the breast near the pectoralis major muscle. The lesion resembled a cancer on mammography and ultrasound.
Brown et al. (10) found that periareolar soft tissue changes and inferior pole alterations were present at 6 months in nearly all of 42 patients following breast reduction, and these findings regressed on subsequent studies. In 50% of patients, calcifications occurred after 2 years. In 10% of patients, there was evidence of fat necrosis on mammography.
Calcifications are a common finding in patients who have had breast reductions (3). Dermal calcifications, which are smooth and round, may occur in the areola (7) or in scars. Areas of fat necrosis are more common in patients who have undergone reduction than those who have had routine biopsies. Calcifications may be eggshell shaped in the walls of oil cysts or may be irregular (11) or even lacy in appearance (Fig. 12.20). The calcifications may be extensive and have a coarse pleomorphic appearance, sometimes raising a concern for cancer because of the pleomorphism. Importantly, these calcifications are oriented in the direction of the scars, and correlation with this distribution is helpful in confirming their etiology. Even sutural calcification may be identified after reduction procedures (8) (Fig. 12.21).
Figure 12.17 HISTORY: A 45-year-old woman after bilateral reduction mammoplasties, with firm nodularity in both subareolar areas.
MAMMOGRAPHY: Right MLO (A) and CC (B) views and left MLO (C) and CC (D) views. The breasts show primarily fatty replacement. There are extensive areas of calcification in both breasts, more prominent on the right than on the left. Many of the calcifications are thin eggshell or rimlike in areas of liponecrosis macrocystica (fat necrosis). On the right (A and B), there is a mixture of the large oil cysts with coarse pleomorphic calcifications. The findings represent dystrophic changes of fat necrosis secondary to reduction mammoplasty. Generally, this extent of fat necrosis is not seen after biopsy or lumpectomy and instead represents a more significant trauma, such as a reduction procedure or severe nonsurgical breast trauma.
IMPRESSION: Extensive changes of fat necrosis, secondary to reduction mammoplasty. (Case courtesy of
Dr. M. C. Wilhelm, Charlottesville, VA.
Figure 12.18 HISTORY: A 50-year-old woman after bilateral reduction mammoplasties, for routine mammogram.
MAMMOGRAPHY: Bilateral MLO (A), left CC (B), and right CC (C) views. There is disorientation of the parenchymal pattern, without the normal flow of ducts toward the nipples (A). This disorientation of parenchyma is a typical postreduction finding. On the CC views (Band C), there are circular, round, and lacy coarse calcifications associated with the dense areas of parenchymal scarring. These findings are seen after reduction mammoplasty and represent dystrophic changes of fat necrosis.
IMPRESSION: Fat necrosis secondary to reduction mammoplasty.
NOTE: The patient was followed for 18 months, and the calcifications were stable.
Figure 12.19 HISTORY: A 58-year-old gravida 6, para 6 woman with history of right breast cancer and of reduction mammoplasty on the left.
MAMMOGRAPHY: Left MLO (A) and enlarged (1.5÷) CC (B) views. The breast is moderately dense. In the left upper-inner quadrant, there is a radiolucent well-circumscribed lesion (curved arrow) with early calcification in the rim, consistent with an oil cyst. Adjacent to the oil cyst are two clusters of coarse pleomorphic microcalcifications (arrows) that had developed since the prior mammogram. Because of their morphology and their association with the nearby oil cyst, these microcalcifications were thought to represent most likely fat necrosis and fibrosis. However, because of the risk status of the patient and the interval change, the area was biopsied.
IMPRESSION: Probable fat necrosis.
HISTOPATHOLOGY: Changes compatible with old biopsy, fat necrosis.
Lumpectomy and Radiation Therapy
During the past two decades, there has been a striking increase in breast conservation procedures for treatment of carcinomas. Several studies (12,13) have shown that the long-term survival of women treated for grade I and II breast cancer with lumpectomy and radiation therapy is similar to that of those treated with mastectomy. Four large, randomized controlled trials evaluating lumpectomy with radiotherapy include the National Cancer Institute of Italy (13), the National Cancer Institute of the United States (14), the European Organization for Research and Treatment of Cancer (15), and the National Surgical Adjuvant Breast Project (12). In these trials, the treatment included whole breast irradiation. Typical radiation therapy for breast cancer is a treatment course over 6 weeks using an external beam. More recently, partial breast accelerated radiotherapy or brachytherapy has been used for certain small invasive cancers. These treatments, which occur over a week, may be delivered through multiple catheters or a balloon inserted into the breast or by an accelerated dose by external beam (16).
Patients who have the option for breast conservation therapy are usually those who have tumor confined to the breast and ipsilateral nodes, a tumor size of <4 cm without fixation, and a size or location of tumor that, after
treatment, will yield satisfactory cosmetic results (3,12). Multicentric carcinoma (17) is also considered by many radiotherapists as a contraindication to breast conservation therapy.
Figure 12.20 HISTORY: A 62-year-old woman with a history of reduction mammoplasty.
MAMMOGRAPHY: Bilateral MLO (A) and CC (B) views show dense parenchyma and postsurgical scars delineated by wire markers in the skin. There is some parenchymal redistribution, with more tissue being located inferiorly and medially. The breasts appear somewhat flattened at the area of the nipple areolar complex, which is elevated in comparison with a nonreduced breast. In addition, there are coarse dystrophic calcifications bilaterally. Those on the right have a dense but eggshell appearance typical of fat necrosis and an oil cyst.
IMPRESSION: Postreduction changes.
Figure 12.21 HISTORY: A 35-year-old woman after reduction mammoplasty, for routine screening.
MAMMOGRAPHY: Left MLO (A) and right MLO (B) views. The breasts are very dense and glandular. Multiple calcified and radiopaque sutures are present bilaterally, corresponding to the scars involved with the reduction procedure.
IMPRESSION: Calcified sutures.
In patients who are treated with lumpectomy and radiation therapy, the rate of local recurrence is in the range of 6% to 10% (18,19,20) and is at a rate of 2% per year (3). There is a significant salvage rate (58% at 5 years, 50% at 10 years) in patients who develop local recurrences after lumpectomy and radiation (21). In a study of treatment methods used for 124 cases of pure ductal carcinoma in situ (DCIS), Warneke et al. (22) found the local recurrence rates to be as follows: 1.3% following mastectomy, 3.2% following lumpectomy and radiation, and 11% following wide excision alone. All the local recurrences after lumpectomy were detected at mammography, and all lesions were salvaged by mastectomy. A majority of local recurrences occur in the same quadrant as the initial primary (20). Because of this, not only whole breast irradiation but also a boost to the tumor bed may be given (23). Careful clinical and mammographic follow-up is necessary in order to detect these recurrences when they are early enough for the patient to be salvaged.
A thorough preoperative evaluation of the patient who is considering breast conservation is necessary to optimize the results. Importantly, the mammographic assessment of the size and extent of tumor is necessary. Ultrasound and magnetic resonance imaging (MRI) are important adjunctive examinations to answer this question. The presence of multiple lesions that are potentially malignant requires biopsy to determine the presence of multifocal (two or more foci in the same quadrant) or multicentric (two or more foci in different quadrants) disease.
An initial postlumpectomy/preradiotherapy mammogram is recommended to serve as a baseline for follow-up studies and to evaluate the breast for residual carcinoma (3,24,25,26,27) (Figs. 12.22 and 12.23). This study should be
performed at least 10 days after surgery, allowing for time for the incision to heal. Comparison must be made with the preoperative mammogram to determine the exact location of the tumor and its appearance. Particularly if the tumor contained microcalcifications, the postoperative study can provide valuable information about the presence of residual calcifications (18,25). Pretreatment postoperative mammography is helpful as an indicator of the adequacy of tumor excision, particularly in cases in which the original tumor presented with microcalcifications. Gluck et al. (28) found the positive predictive value for residual tumor to be 0.69; when the tumor was DCIS and when more than five microcalcifications were present at the lumpectomy site, the positive predictive value was 0.90. However, the negative predictive value of the absence of residual microcalcifications was 0.64 for all tumor types and was 1.0 for the noncomedo subtype of DCIS.
In addition, the pretreatment mammogram can serve as a new baseline before radiotherapy. Teixidor et al. (29) found the preradiotherapy mammogram to be helpful for interpretation of the subsequent studies in 32% of patients. In 5% of patients, residual tumor was identified on the pretreatment study as well.
On this baseline, normal expected findings are skin thickening at the lumpectomy site, architectural distortion, and oftentimes a fluid collection. In a study of the imaging findings after breast conservation therapy, Mendelson (4) found that approximately one half of 110 patients had a fluid collection at the surgical site. Most often the size of the hematoma/seroma was 3 to 5 cm. Postoperative hematomas are of maximum size on this initial baseline study and gradually diminish in size, becoming more irregular in contour. When a patient is found to have irregular density on a 6-month posttreatment mammogram, it is extremely useful to have a baseline postoperative study that showed a larger hematoma at the site.
Normal mammographic and clinical changes that may be expected after breast conservation therapy include (a) local changes that the tumor bed related to surgery and (b) diffuse changes related to irradiation (Figs. 12.24,12.25,12.26,12.27,12.28,12.29,12.30,12.31,12.32,12.33,12.34,12.35,12.36). Mammography is necessary for accurate monitoring of the postirradiation changes as well as the possible development of recurrent carcinoma (24). DiPiro et al. (30) in a study of the role of routine magnification views in patients after breast conservation therapy for breast cancer, suggested that the magnification view was necessary to evaluate equivocal microcalcifications. In 4% of cases, the magnification view influenced the decision to perform a biopsy. However, the authors did not find the magnification views helpful when conventional views of the breast were not questionable.
At 6 to 12 months, the maximum changes of increased interstitial markings and skin thickening are seen. These diffuse findings are secondary to the edema from irradiation of the breast. These edematous changes will stabilize and then diminish, usually at 2 years or later (3). The skin thickness may increase to as much as 1 cm. Dershaw et al. (31) found that in 160 women treated with lumpectomy and radiation therapy, 96% had skin thickening, which stabilized by 1 year. At 3 years, 50% of women had persistent edema and skin thickening.
The latent normal changes after radiation are the development of calcifications of fat necrosis, developing usually after 1 year. Libshitz et al. (32) found that benign calcifications developed in treated breasts from 2 to 44 months after irradiation. These calcifications have the same mammographic appearance of liponecrosis microcystia secondary to trauma or biopsy, and they may occur at the lumpectomy site or elsewhere in the treated breast. Brenner and Pfaff (33) found that although all the normal postoperative changes other than calcifications resolved over time, architectural distortion showed the most significant change (p = 0.05).
In a study of 123 patients treated with breast conservation therapy, Cox et al. (34) found that 27% of patients never developed a scar on mammography; in the 73% of patients with a scar, the mean decrease in scar size was 16.7 mm over the study period of 4 years. Calcifications developed in 16% of patients between 6 and 48 months after treatment. Recurrent cancer was found in 2% of patients. Others (31,35) have described the development of calcifications that are coarse and round in one third to one half of irradiated breasts.
Serial mammography and clinical examination of the treated breast are complementary for the optimal detection of recurrence. Hassell et al. (36) found that in 24 patients with recurrent carcinoma, 7 had positive mammographic findings alone, 9 had positive clinical examination alone, and 8 had both positive mammography and clinical examination. Most common mammographic findings were new microcalcifications or a new mass. Orel et al. (37), in a series of 38 biopsy-proven recurrences, found that 34% were found by mammography alone, 45% with palpation alone, and 21% by both methods. A majority (55%) of recurrences were in the lumpectomy quadrant.
The findings of recurrent carcinoma include the development of new microcalcifications, increased skin thickening after stabilization, increased density (particularly at the tumor bed) after stabilization, and the development of a new mass (Figs. 12.37,12.38,12.39,12.40,12.41). Because of the difficulty in differentiating benign from malignant microcalcifications with certainty, biopsy is indicated unless the calcifications are those of fat necrosis.
New spiculated masses and irregular ductal-type malignant microcalcifications are highly suspicious for recurrence. Stomper et al. (38) found that 65% of recurrences in 23 women occurred at the primary site, 22%
recurred in different sites, and 13% were multifocal. Dershaw et al. (39) found that microcalcifications were the most common presentation of recurrence (19 of 29 cases), and a mass with or without calcifications was less frequent (10 of 29 cases). Two of the recurrences that were masses were evident as enlargement of the scar. The positives rates for recurrent tumor on biopsies for mammographic or clinical abnormalities in treated breasts range from 20% to 58% (26,40,41,42). A combination of clinical findings and mammographic findings is highly suspicious for recurrence; careful attention to and comparison with all previous studies, not just the most recent, are necessary.
Figure 12.22 HISTORY: A 31-year-old woman who had a lumpectomy for a palpable carcinoma in the left axillary tail 3 weeks earlier. She was referred for radiation therapy, and a postoperative baseline mammogram was obtained.
MAMMOGRAPHY: Left MLO (A), right MLO (B), and left CC (C) views. The scar from the recent lumpectomy is evident as a flat irregular density in the upper outer quadrant (curved arrow) (A and C). There is asymmetry of the left supra-areolar area (arrow) in comparison with the right breast (B). A focal area of increased density is present, and on the CC views (C), it appears finely spiculated(arrow). This supra-areolar lesion is suspicious for residual multicentric nonpalpable carcinoma.
IMPRESSION: Highly suspicious for residual carcinoma, separate focus, left breast.
HISTOPATHOLOGY: Infiltrating ductal carcinoma.
NOTE: This case demonstrates the importance of obtaining a mammogram, even in a young patient, before definitive therapy to confirm the absence of residual carcinoma.
Figure 12.23 HISTORY: A 66-year-old gravida 2, para 2 woman with a family history of breast cancer, for screening.
MAMMOGRAPHY: Left MLO (A) and enlarged exaggerated CC lateral (B) views, specimen radiograph (C), and enlarged left ML (D) and CC (E) views after biopsy. On the initial mammogram, a cluster of innumerable, irregular malignant calcifications (arrows) is seen (Aand B). The specimen radiograph (C) following needle localization and excision demonstrates the calcifications, which were noted to extend to the edge of the tissue. Histopathology demonstrated intraductal carcinoma of the comedo type, extending close to the surgical margin. The patient wished to have breast conservation therapy. The postbiopsy, preradiotherapy baseline mammogram (D and E) demonstrates residual malignant-appearing calcifications at the lumpectomy site (arrows). The spiculated soft-tissue density (curved arrow) represents postoperative hematoma.
IMPRESSION: Preradiotherapy baseline mammogram demonstrating residual carcinoma.
HISTOPATHOLOGY: Residual DCIS.
Figure 12.24 HISTORY: A 62-year-old woman who is status postlumpectomy and radiation for breast cancer.
MAMMOGRAPHY: Bilateral CC (A) and MLO (B) views show that the right breast is smaller and retracted in comparison with the left. There is an irregular spiculated mass at the lumpectomy site, consistent with postsurgical scar. There are dystrophic calcifications in the scar and scattered elsewhere throughout both breasts. Diffuse skin thickening is present on the right secondary to radiation therapy as well.
IMPRESSION: Postlumpectomy and radiation therapy changes, right breast.
Figure 12.25 HISTORY: A 49-year-old woman who is status postlumpectomy and radiation therapy for right breast DCIS.
MAMMOGRAPHY: Bilateral MLO (A) and CC (B) views show marked asymmetry in the appearance of the breasts. The right is smaller and diffusely more dense than the left, related to the effects of radiation therapy. A postsurgical scar is demarcated by surgical clips in the 10 o'clock position. On the spot MLO magnification view (C), the scar is better seen and is noted to contain radiolucencies consistent with evolving oil cysts.
IMPRESSION: Normal posttreatment changes.
Figure 12.26 HISTORY: Patient with a history of left breast invasive ductal carcinoma, treated with lumpectomy and radiation therapy.
MAMMOGRAPHY: Left CC (A) view before surgery shows a high-density lobular mass with spiculated margins, consistent with carcinoma. Six months after treatment, the left CC (B) and MLO (C) views show a large round mass with somewhat indistinct margins extending toward the skin (arrow). This is a normal postlumpectomy finding: hematoma or seroma. One year later, the left CC view (D) shows that the seroma is retracting and in doing so is more dense and spiculated.
IMPRESSION: Normal evaluation of seroma at lumpectomy site.
Figure 12.27 HISTORY: Postmenopausal patient who is status posttreatment of right breast cancer with lumpectomy and radiation therapy.
MAMMOGRAPHY: Right MLO (A) and CC (B) views show a spiculated mass at the surgical site, which is consistent with postsurgical scar. The area has a different appearance on the two views. On the MLO, it is contiguous with the skin and associated with the scar on the skin. Diffuse skin thickening related to radiation therapy is also noted.
IMPRESSION: Postsurgical and radiation changes.
The differentiation of posttreatment scar and recurrence can sometimes be difficult on mammography alone. The temporal changes from prior mammography determine the approach to patients. In cases in question, contrast-enhanced MRI is very helpful to differentiate scar from tumor. Heywang-Köbrunner et al. (43) found that in the early posttreatment period (up to 9 months), MRI was not helpful because of the strong enhancement present; however, after 18 months, MRI detected all recurrences correctly as diffuse or focal areas of enhancement.
Figure 12.28 HISTORY: A 47-year-old woman with a history of DCIS treated with lumpectomy and radiation therapy.
MAMMOGRAPHY: Left CC views (A) show a wire marking the lumpectomy site. Postsurgical scarring is present, extending toward the chest wall. Within the scar, there is a small radiolucent mass (arrow) better seen on the magnification view (B).
IMPRESSION: Oil cyst within the lumpectomy site, fat necrosis.
Figure 12.29 HISTORY: A 58-year-old woman who is 7 years status post–breast conservation therapy for left breast cancer.
MAMMOGRAPHY: Bilateral MLO views (A) 1 year ago demonstrate minimal distortion in the left breast superiorly, as demonstrated by a scar marker on the skin. Mild skin thickening is present as well, and the breast appears smaller and somewhat retracted compared with the right. On the current MLO views (B), the scar is slightly less prominent, and the other changes are stable.
IMPRESSION: Normal changes following breast conservation with lumpectomy and radiation therapy.
Figure 12.30 HISTORY: A 50-year-old gravida 4, para 4 woman after lumpectomy for a carcinoma in the right upper-outer quadrant and referred for radiation therapy. A preliminary mammogram, after lumpectomy and before radiotherapy, was obtained.
MAMMOGRAPHY: Right MLO (A) and CC (B) views 1 month after lumpectomy, and right MLO (C) and CC (D) views 6 months later. On the postlumpectomy films (A and B), a large, medium-density, partially circumscribed mass is present at the surgical site and is consistent with a postoperative hematoma. Six months after therapy (C and D), the hematoma has resolved, and there is a small residual area of increased density, consistent with scar and fat necrosis (arrows). There is also a mild increase in the overall density of the interstitium and an increase in skin thickness that are normal postradiation changes.
IMPRESSION: Normal evolution of postlumpectomy and radiation changes in the acute-subacute phase.
NOTE: It is not unusual to see a hematoma on the baseline postlumpectomy study. The mammogram can usually be performed with adequate compression of the breast 10 days or more after lumpectomy.
Figure 12.31 HISTORY: A 66-year-old gravida 3, para 3 woman who was referred for radiation therapy after a lumpectomy and axillary dissection in the left upper-outer quadrant.
MAMMOGRAPHY: Left MLO view 3 weeks after lumpectomy (A) and left MLO views 6 months (B) and 12 months (C) later. On the initial postoperative film (A), there is architectural distortion associated with irregular areas of increased density in the left upper-outer quadrant and in the axilla (arrows). The density represents hematoma and postsurgical change, and the examination will serve as a baseline for the follow-up after radiotherapy. Six months after treatment (B), the distortion from the scar persists, but the hematoma and surrounding density have significantly decreased in size. Very minimal increase in interstitial markings is seen, an effect of radiotherapy. On the study 1 year after treatment (C), further diminution in the density is seen as would be expected, and there are no new findings to suggest recurrence.
IMPRESSION: Postlumpectomy scarring showing resolution.
Figure 12.32 HISTORY: A 67-year-old gravida 6, para 5 woman with a positive family history of breast cancer, for routine screening.
MAMMOGRAPHY: Right oblique (A) and CC (B) views from April 1988, right MLO (C) and CC (D) views from April 1989, and right MLO (E) and CC (F) views from October 1989. On the initial screening examination (A and B), there is a high-density spiculated mass in the upper outer quadrant (arrows). The lesion was considered highly suspicious and was biopsied after needle localization. The histopathology demonstrated infiltrating ductal carcinoma, and the patient was treated with lumpectomy and radiation therapy. One year later (C and D), the breast is diffusely edematous, with prominent interstitial markings, increased density, and skin thickening. These are normal changes in the first year after radiation therapy. At 18 months after diagnosis (E and F), the edema pattern secondary to radiation is decreasing. There also has been a decrease in skin thickening. The scar in the upper outer quadrant is evident (arrow), but there are no changes to suggest recurrence.
IMPRESSION: Normal evolution of postradiation changes after treatment of primary breast carcinoma.
Figure 12.33 HISTORY: A 65-year-old woman treated with lumpectomy and radiation therapy for infiltrating ductal carcinoma of the right breast.
MAMMOGRAPHY: Prebiopsy right MLO view (A) and posttreatment right MLO views at 6 months (B) and at 12 months (C). On the initial study (A), there is a high-density spiculated mass deep in the right breast, consistent with carcinoma. This was biopsied after a needle localization, and histopathology revealed infiltrating ductal carcinoma. On the next examination (B), 6 months after lumpectomy and radiation therapy, the breast is diffusely more dense and does not compress as well. There is a focal irregular density (arrow) at the lumpectomy site that is most consistent scar and fat necrosis. Subsequently, at 12 months posttreatment (C), there has been a decrease in the edema of the breast as well as a decrease in the size and density of the scar and fat necrosis.
IMPRESSION: Normal evolution of postoperative and radiation changes.
Figure 12.34 HISTORY: A 78-year-old woman with a history of right breast cancer, treated with lumpectomy and radiation therapy.
MAMMOGRAPHY: Right MLO (A) and CC (B) views show an area of architectural distortion beneath the wire marker, consistent with postsurgical scar. On the spot magnification (C), the area is noted to be highly spiculated and contain small punctuate and amorphous microcalcifications.
IMPRESSION: Postsurgical scar containing indeterminate microcalcifications. Recommend needle biopsy.
HISTOPATHOLOGY: Fat necrosis, foreign body giant cell reaction, hemosiderin laden macrophages, microcalcifications.
A rare complication of breast irradiation is the development of radiation-induced sarcoma (RIS). The rate of RIS has been reported to be 0.18% (44), and the mean latency period after treatment is 5.5 to 9 years (45). Angiosarcoma typically presents as a painless mass that may be associated with overlying blue or purplish discoloration of the skin (45).
Imaging of the Mastectomy Site
Although a majority of physicians do not recommend routine imaging of the mastectomy site to search for cancer recurrence, there is some literature that supports the value of mammography or sonography in these patients. Rissanen et al. (46) evaluated the roles of mammography and ultrasound in the diagnosis of local and regional recurrences in patients who had undergone mastectomy. The authors found the sensitivity of ultrasound to be the highest at 91%, with the sensitivities of clinical examination and mammography to be 79% and 45%, respectively. Most recurrent cancers were seen as circumscribed masses on mammography and hypoechoic lesions at ultrasound (Fig. 12.42). In addition, if the mastectomy site is imaged, benign lesions may be observed. Fat necrosis as evidenced by oil cysts or dystrophic calcifications may be seen on mammography (Fig. 12.43).
Figure 12.35 HISTORY: An 80-year-old woman who is 7 months status posttreatment of right breast cancer with lumpectomy and radiation therapy.
MAMMOGRAPHY: Right MLO (A) and CC (B) views show architectural distortion at the lumpectomy site, marked by a wire, consistent with postsurgical scar. On the magnification ML view (C), there are fine linear microcalcifications (arrow) at the anterior edge of the biopsy site, suspicious for recurrence of carcinoma. Biopsy of these calcifications was performed.
IMPRESSION: Microcalcifications suspicious for recurrence of carcinoma.
HISTOPATHOLOGY: Benign breast tissue with fibrosis and microcalcifications.
Figure 12.36 HISTORY: A 68-year-old gravida 6, para 4 woman for follow-up after lumpectomy and radiation therapy on the right for infiltrating lobular carcinoma. She had also undergone a re-excision at the tumor bed for new microcalcifications found to be atypical epithelial hyperplasia.
MAMMOGRAPHY: Right MLO (A) and magnification (2÷) (B) views at the tumor bed 2 years after treatment. There is irregular increased density at the lumpectomy site, consistent with postsurgical scar. There are curvilinear coarse calcifications at the biopsy site(A, curved arrow) seen better on the magnification view (B). Behind the curvilinear calcifications is a group of calcifications in a knotted shape (A and B). The smooth curvilinear shape of the calcifications is typical of sutural calcification.
IMPRESSION: Sutural calcifications.
Certainly in patients in whom a prophylactic subcutaneous mastectomy has been performed, mammography is necessary. In these patients, the nipple areolar complex is not removed. Because the nipple remains, the ducts remain; therefore, carcinoma can still develop in the residual tissue.
In most cases, patients who have had a total or modified radical mastectomy and reconstruction are not imaged. The reconstruction may be performed by placement of an expandable implant or by plastic repair with a myocutaneous flap (Fig. 12.44). Several types of myocutaneous flaps have been used for breast
reconstruction, including those from the transversus rectus abdominis muscle and the latissimus dorsi muscle. One complication of this procedure, which is related to maintaining an adequate blood supply, is fat necrosis of the flap (47) (Fig. 12.45). The patient presents with a firm mass (48,49), and the differential diagnosis includes recurrent carcinoma or fat necrosis. Mammography may be used in this circumstance and may demonstrate changes of fat necrosis ranging from an irregular increased density to radiolucent oil cysts to ringlike calcifications characteristic of a benign process. Recurrent carcinoma in the flap may be clinically suspected because of development of a palpable mass (Fig. 12.46). Mammography demonstrates a mass that is most often located peripherally, at the junction of the flap with the native tissue.
Figure 12.37 HISTORY: A 58-year-old woman who was status postlumpectomy and radiation therapy to the left breast, 20 years ago.
MAMMOGRAPHY: Left MLO (A) and CC (B) views show heterogeneously dense tissue and minimal scarring marked by a wire on the skin. In the 2 o'clock position, just posterior to the lumpectomy site, are clustered microcalcifications (arrows). On the enlarged MLO image (C), the pleomorphic and fine linear morphologies of the calcifications are noted.
IMPRESSION: Highly suspicious for recurrence of carcinoma.
HISTOPATHOLOGY: DCIS, intermediate grade, solid type.
Figure 12.38 HISTORY: Routine follow-up for a 48-year-old patient who is status postlumpectomy and radiation therapy for left breast ductal carcinoma.
MAMMOGRAPHY: Left magnification CC view. There is architectural distortion at the site of the lumpectomy. Within this distortion are innumerable fine, pleomorphic, linear, and branching microcalcifications. This appearance is highly suggestive of carcinoma and is not a benign postsurgical change.
IMPRESSION: Highly suspicious for malignancy, BI-RADS® 5.
HISTOPATHOLOGY: High-grade DCIS with comedonecrosis.
Figure 12.39 HISTORY: A 55-year-old woman 1 year status postlumpectomy and radiation therapy for right breast ductal carcinoma.
MAMMOGRAPHY: Right magnification ML (A) and MLO (B) and enlarged images (C, D) show the lumpectomy site delineated by surgical clips. There are a few very faint, fine linear microcalcifications just inferior to the tumor bed. Stereotactic core needle biopsy was performed.
IMPRESSION: Highly suspicious for recurrent carcinoma.
HISTOPATHOLOGY: High-grade DCIS.
Figure 12.40 HISTORY: A 49-year-old woman who is status postlumpectomy and radiation therapy for right breast cancer.
MAMMOGRAPHY: Right MLO (A) and CC (B) views from 1993 show normal postoperative changes. There is a scar located posterolaterally (arrow) and skin thickening diffusely related to normal postradiation changes. On the subsequent mammogram (C, D)in 1994, there has been interval development of a new, small indistinct mass (arrow) medial to the tumor bed. Core needle biopsy was performed.
IMPRESSION: Findings suspicious for recurrent carcinoma.
HISTOPATHOLOGY: Recurrent invasive ductal carcinoma.
Figure 12.41 HISTORY: A 39-year-old gravida 1, para 1 woman 20 months after treatment for stage I breast carcinoma with lumpectomy and radiation therapy. She became pregnant and delivered a child approximately 12 months after radiation therapy was completed.
MAMMOGRAPHY: Left MLO view (A) and ultrasound (B) 4 weeks after lumpectomy, left MLO view (C) 14 months after lumpectomy and radiotherapy, and left MLO (D) and CC (E) views 18 months after lumpectomy. On the initial postlumpectomy mammogram (A), there is a large, high-density, relatively circumscribed mass at the biopsy site. On ultrasound (B), this mass is relatively anechoic, consistent with a postoperative hematoma or seroma. The mammogram 1 year later, when the patient was postpartum (C), demonstrates an irregular medium-density mass at the lumpectomy site. This had decreased in size considerably from the postoperative mammogram and was thought to represent most likely postoperative scarring. However, because of the lack of sequential mammograms, a repeat study in 3 months was recommended. On the final films (D and E) 4 months later, there is a high-density spiculated lesion at the lumpectomy site. (Clinical examination revealed increased induration in this area.) The findings are highly consistent with recurrent carcinoma in the treated breast.
IMPRESSION: Sequence of changes demonstrating a recurrent carcinoma in the treated breast.
NOTE: The lumpectomy site should never become larger. It may become more irregular and more dense as the hematoma retracts, but it should not increase in size.
Figure 12.42 HISTORY: A 51-year-old woman 6 years after right mastectomy and reconstruction with an expandable implant. She presented with palpable thickening of questionable duration, inferior to the mastectomy scar.
MAMMOGRAPHY: Right MLO view (A), right ML view (B), and ultrasound (C). A wire is present over the scar, and a BB overlies the palpable nodule. A small focal area of irregular tissue (arrow) is present beneath the BB (A and B). The ultrasound (C) clearly demonstrates the hypoechoic nodule (arrow) in the subcutaneous area.
IMPRESSION: Recurrent carcinoma.
CYTOLOGY: Positive for malignancy.
Figure 12.43 HISTORY: A 62-year-old woman who is status post–left mastectomy, who presents with an abnormal mammogram of the mastectomy site.
MAMMOGRAPHY: Left MLO (A) and exaggerated CC lateral (B) views show residual fatty tissue at the mastectomy site. In the upper outer aspect is a group of coarse calcifications that are forming a circle. The pattern of the dystrophic calcification is typical for fat necrosis.
IMPRESSION: Benign calcifications of fat necrosis in the mastectomy site.
Figure 12.44 HISTORY: A 59-year-old patient who is status postmastectomy and reconstruction with a myocutaneous flap.
MAMMOGRAPHY: Left MLO (A) and CC (B) views show primarily fatty tissue with some density in the upper outer aspect of the flap. The shape of the breast is somewhat flattened and less pendulous than the normal breast, and the skin is slightly thickened. No ductal tissue is present.
IMPRESSION: Reconstructed breast with a transversus rectus abdominis myocutaneous (TRAM) flap.
Figure 12.45 HISTORY: A 51-year-old woman after left breast cancer treated with a modified radical mastectomy and reconstruction with a myocutaneous flap. She presents with a palpable mass in the upper aspect of the reconstruction breast.
MAMMOGRAPHY: Left MLO (A) and CC (B) views and ultrasound (C and D). The wires mark the surgical scar, and the BB marks the palpable nodule. There is no ductal tissue present; instead, the reconstructed breast is composed of bandlike densities of muscle, fascia, and fatty tissue (A and B). In the upper central aspect, there is an irregular mass (arrow) (B). On ultrasound, the superior aspect of the density is complex, containing fluid and echogenic components (C), most consistent with an organizing hematoma. Adjacent to the hematoma is a focal area of shadowing (D, arrow), which could represent fat necrosis, fibrosis, or tumor. This shadowing corresponded to the palpable nodule and was biopsied.
IMPRESSION: Reconstructed left breast with a palpable hematoma and a solid shadowing area representing either fat necrosis or recurrent tumor.
HISTOPATHOLOGY: Fat necrosis, lipogranuloma, foreign body giant cell reaction.
Figure 12.46 HISTORY: A 36-year-old woman who is status post–left mastectomy for invasive carcinoma and transverse rectus abdominis myocutaneous (TRAM) flap reconstruction. She presents with a palpable lump in the medial aspect of the reconstructed breast.
MAMMOGRAPHY: Bilateral MLO views (A) show a heterogeneously dense right breast. The TRAM flap on the left is completely fatty. There is a large, lobulated, relatively circumscribed mass in the left upper-inner quadrant. On the enlarged CC view (B), the multilobular dense mass is seen. The location in the upper inner quadrant and the appearance of the mass do not suggest fat necrosis.
IMPRESSION: Recurrence of carcinoma in the reconstructed breast.
HISTOPATHOLOGY: Poorly differentiated carcinoma.