Thickening of the skin over the surface of the breast may occur in primary inflammatory carcinoma, other malignancies, and several benign conditions. It is important for the radiologist to be aware of ranges for normal thickness and to evaluate the skin carefully on the mammogram to detect an alteration that may be associated with an underlying disease process.
Although the normal skin thickness of the breast has been described as generally less than 1.5 mm (1), a study by Wilson et al. (2) of 150 normal patients showed the range to vary from 0.8 to 3 mm in thickness. In 92% of patients, the medial skin thickness was greater than the lateral skin thickness, and in 91% of patients, the skin was thicker inferiorly than superiorly. The mean thickness of the skin was greater in smaller breasts. In a study of skin thickness in 250 asymptomatic women, Pope et al. (3) found that the medial and inferior aspects of the breast skin were thickest and that the maximum thickness was 2.7 mm. Table 9.1 shows the ranges of skin thickness for different sizes of breasts as determined by Wilson et al. (2).
Edema of the breast is characterized by an increase in skin thickness and prominence of the interstitial or trabecular markings. A thickened skin pattern may occur with primary breast cancers, with metastatic carcinoma to the breast, or in a number of benign conditions (4) (Table 9.2) that cause the interstitium to be distended or edematous.
Malignant Causes of the Thickened Skin Pattern
Locally Advanced Breast Cancer
Breast cancer may extend locally into the subcutaneous fat and produce focal skin thickening and/or retraction, indicating locally advanced disease (Figs. 9.1,9.2,9.3). Dunkley et al. (5) found skin thickening on mammography in 24% of breast cancer patients; in 68% of these patients, the skin thickening seen on mammography was not evident on clinical examination. This thickening of skin is focal and is much less generalized than the skin edema associated with inflammatory carcinoma. In addition, the erythematous pitting edema of inflammatory breast cancer is not usually present in these cases.
Inflammatory breast cancer was described in Bell's surgery text of 1816 (6,7) as “a purple color on the skin over the tumor accompanied by shooting pains.” Because of the involvement of the dermis, a diffuse edema pattern with skin thickening is seen in inflammatory carcinoma. Inflammatory cancer can account for 1% to 4% of breast cancers (8), with an average age at onset of 52 years (7). Inflammatory breast cancer is a stage IIIB, locally advanced lesion and has a poor prognosis.
In inflammatory breast cancer, the patient presents clinically with a tender, firm, heavy breast with purplish discoloration and a peau d'orange thickening of the skin. The clinical presentation is often indistinguishable from mastitis. A focal mass may be palpable, or the entire breast may be hardened. Biopsy of the skin is used to diagnose this entity; the hallmark pathologic feature is involvement of the dermal lymphatics with tumor emboli.
Mammographically, skin thickening and a marked increase in the density of the breast are seen (Figs. 9.4,9.5,9.6,9.7,9.8). Much of this density is caused by edematous changes in the trabeculae or interstitium of the breast. The breast affected by inflammatory carcinoma is less compressible on positioning for mammography, and the overall size of the breast on the mammogram may appear to be less than the normal breast because of its hardness and lack of compressibility. The underlying tumor mass may be evident on mammography, or the density may be so great because of the edema and the decreased compression of the thickened breast that evaluation of the underlying parenchyma is unsatisfactory.
In a review of 142 cases of pathology-proven inflammatory breast cancer, Günhan-Bilgen et al. (10) found the following manifestations on mammography: skin thickening in 84%, trabecular thickening in 81%, a mass in 16%, an asymmetric focal density in 61%, and microcalcification
in 56%. Sonography showed skin thickening in 96% and a solid mass in 80%. Ultrasound was helpful in the depiction of masses that were obscured by the edema pattern as well as in the demonstration of skin and pectoral muscle invasion and axillary involvement. In another series, Kushwala et al. (11) found that mammographic findings of skin and trabecular thickening were common (92% and 62%, respectively) and that masses and microcalcifications were uncommon manifestations of inflammatory breast cancer. Dershaw et al. (12), however, found that a vast majority of patients with inflammatory breast cancer had an edema pattern as well as an associated mass or malignant microcalcifications on mammography.
TABLE 9.1 Range of Normal Skin Thickness
TABLE 9.2 Causes of Skin Thickening
Figure 9.1 HISTORY: A 58-year-old woman with a palpable breast mass and overlying skin retraction.
MAMMOGRAPHY: Left spot CC view shows a large lobular mass with spiculated margins and associated pleomorphic microcalcifications. Overlying skin thickening and retraction are noted, as well as edema surrounding the mass.
IMPRESSION: Carcinoma, locally advanced.
HISTOPATHOLOGY: Invasive ductal carcinoma.
Sonography is often more helpful than mammography in identifying malignant masses in patients with inflammatory breast cancer. Sonography is also useful in defining the extent of inflammatory carcinoma, including the involvement of lymph nodes in the axillary and supraclavicular areas (13). The skin thickness can be measured on sonography, and a decrease in skin thickening can be used to quantify the response to chemotherapy (Figs. 9.9 and 9.10).
Figure 9.2 HISTORY: A 46-year-old woman for screening.
MAMMOGRAPHY: Left MLO view (A) and magnified image (B). The breast is quite dense and glandular. There is focal skin thickening(arrow) on the lower aspect of the breast. Beneath the thickening is a 1-cm spiculated mass that is tethering the skin by fine spicules (B).
IMPRESSION: Focal skin thickening associated with underlying carcinoma.
HISTOPATHOLOGY: Infiltrating ductal carcinoma.
Figure 9.3 HISTORY: A 64-year-old woman with a left breast mass and dimpling of the skin.
MAMMOGRAPHY: Left CC view. A high-density spiculated mass is present in the subareolar area. Long spicules surround the mass and extend anteriorly to the periareolar area, where they tether the skin. Focal prominent skin thickening is seen. The findings are typical of malignancy.
IMPRESSION: Highly suspicious for locally advanced breast cancer.
HISTOPATHOLOGY: Infiltrating lobular carcinoma, with 1 of 16 nodes positive.
Figure 9.4 HISTORY: A 49-year-old woman with swelling of the left breast.
MAMMOGRAPHY: Left CC views (A) show generalized increase in density of the left breast with abnormal skin thickening in the periareolar area. The right breast (B) has a normal appearance. There is also a spiculated mass (arrow) in the medial aspect of the left breast highly suspicious for carcinoma. A prominent asymmetric density is noted laterally, probably also representing malignancy.
IMPRESSION: Inflammatory breast cancer, left breast.
HISTOPATHOLOGY: Multicentric invasive ductal carcinoma with involvement of dermal lymphatics.
Figure 9.5 HISTORY: A 60-year-old woman who presented with a red, tender, very firm left breast with a 15-cm palpable mass in the upper outer quadrant.
MAMMOGRAPHY: Bilateral MLO views. There is markedly increased density of the left breast relative to the right. Diffuse increase in density of the stroma is noted with marked thickening of the skin diffusely. A large rounded mass is noted in the left upper-outer quadrant.
IMPRESSION: Inflammatory carcinoma.
HISTOPATHOLOGY: Infiltrating ductal carcinoma, with tumor in lymphatics (inflammatory).
NOTE: The concurrent finding of a mass with the marked skin thickening in older patients makes the level of suspicion for carcinoma extremely high.
Figure 9.6 HISTORY: A 55-year-old woman reporting swelling and pain in the left breast.
MAMMOGRAPHY: Bilateral MLO (A) and CC (B) views show marked increase in size and density of the left breast. There is marked skin and trabecular thickening present. Multiple enlarged nodes are also noted in the left axilla.
IMPRESSION: Inflammatory breast cancer with metastatic nodes in the axilla.
HISTOPATHOLOGY: Invasive ductal carcinoma, high nuclear grade, with involvement of dermal lymphatics.
Figure 9.7 HISTORY: A 66-year-old with heaviness of the left breast.
MAMMOGRAPHY: Left MLO (A) and CC (B) views show marked increase in density with trabecular thickening of the left breast. In addition, in the right breast on the MLO (C) and CC (D) views are two areas of architectural distortion located laterally (arrows).
IMPRESSION: Edema pattern of the left breast, suspicious for inflammatory carcinoma. Two suspicious lesions right breast. Recommend biopsy.
HISTOPATHOLOGY: Carcinoma left breast involving dermal lymphatics; multicentric invasive lobular carcinoma of the right breast.
Figure 9.8 HISTORY: Elderly woman with a large palpable mass in the right breast and overlying skin thickening and erythema.
MAMMOGRAPHY: On right MLO (A) and CC (B) views, there is a large, very-high-density mass that is occupying the breast. The mass contains extensive pleomorphic microcalcifications, and there is marked overlying skin thickening as well.
IMPRESSION: Highly suspicious for inflammatory carcinoma.
HISTOPATHOLOGY: Poorly differentiated carcinoma involving dermal lymphatics.
The mammographic finding of diffuse skin thickening and increase in density of the breast may be present several weeks before the clinically inflammatory signs appear (14). Keller and Herman (15) found that patients with inflammatory cancers had an average skin thickness of 6 mm and diffuse increase in density on mammography, compared with a skin thickness of 9 mm and a prominent reticular pattern in patients with a benign cause of a breast edema pattern. Patients with locally advanced breast cancer and secondary inflammatory changes may have a similar clinical presentation to those patients with inflammatory breast cancer (7)—namely, edema of the breast.
Pathologically, the two are different. In inflammatory breast cancer, tumor emboli are present within dermal lymphatics and cause edema of the skin (Fig. 9.11). In locally advanced breast cancer with skin involvement focally, the dermal lymphatics are not involved with tumor.
On magnetic resonance imaging (MRI), inflammatory breast cancer has been found (16) to have a strong signal on the T2-weighted images in the retromammary and the subcutaneous area. Rieber et al. (17), however, found that it may be difficult to distinguish inflammatory carcinoma from mastitis based on the presence of edema alone. MRI is helpful in demonstrating other findings in the patient with an edematous breast. Subtracted images will demonstrate the underlying tumor that may not be evident on mammography because of the marked overlying edema and breast density. In addition, the thickened skin will show enhancement on the T1-weighted postcontrast and subtraction images (Fig. 9.12).
Figure 9.9 HISTORY: A 58-year-old woman who is status post–right mastectomy and breast reconstruction with a transverse rectus abdominis myocutaneous (TRAM) flap. She now presents with a painful, heavy, reconstructed right breast.
MAMMOGRAPHY: Left (A) and right (B) MLO views show asymmetry of the appearance of the breasts consistent with the history of mastectomy and reconstruction on the right. In the right breast, there is no parenchyma present. The skin appears thickened on the right, and this edema is better demonstrated (arrow) on a spot view of the axillary tail (C). Clinical examination demonstrated erythema of the native skin of the breast extending down to the suture line of the TRAM flap. Ultrasound (D, E) shows marked edema of the skin. The thickness was greater than 4 mm throughout the area of erythema, suggesting an inflammatory recurrence of carcinoma.
IMPRESSION: Inflammatory carcinoma, recurrent.
HISTOPATHOLOGY: Poorly differentiated carcinoma in dermal lymphatics.
Figure 9.10 HISTORY: A 70-year-old woman who presents with a palpable left breast mass.
MAMMOGRAPHY: Left MLO (A) and CC (B) views show a large lobulated mass occupying the lower central aspect of the left breast. There is marked skin thickening (arrow) associated with the mass (C), as well as diffuse trabecular thickening. The mass is highly malignant in appearance on ultrasound (D). An enlarged, abnormal-appearing lymph node is present in the left axilla on mammography, and the node is also demonstrated on ultrasound (E).
IMPRESSION: Inflammatory carcinoma with axillary nodal metastases.
HISTOPATHOLOGY: Invasive ductal carcinoma poorly differentiated with metastatic disease in the nodes.
Figure 9.11 Low power histologic section of the skin and subcutaneous tissue showing plugs of malignant cells within dermal lymphatics (arrows). This is the hallmark pathologic feature of inflammatory breast cancer.
Another malignant cause of diffuse skin edema is metastatic disease to the breast from a nonbreast primary carcinoma. Metastatic disease may manifest itself as skin thickening (18) by diffusely invading the dermal lymphatics or by producing impaired lymphatic drainage of the breast by involving the axillary nodes. Lymphangitic metastases to the breast may occur from contralateral breast cancer (19), as well as from other malignancies, including ovarian and endometrial cancers and melanoma (Figs. 9.13 and 9.14).
Lymphomas and pseudolymphomas may produce an appearance of edema secondary to either infiltration of the breast or lymphatic obstruction from malignant axillary nodes. Primary lymphoma of the breast tends to infiltrate the lobules, surrounding and compressing the ducts (20), and mammographically presents as a mass with minimal spiculation (21). Secondary lymphomatous involvement of the breast may produce a focal mass or may present as diffuse increase in density with skin thickening (21). Sabaté et al. (22), in a review of 28 patients with lymphoma, found that unilateral diffuse involvement of the breast occurred in 25% and bilateral diffuse involvement occurred in 8.3% of the cases of primary lymphoma. In secondary lymphoma, diffuse breast involvement occurred in 31.2% of cases. The authors observed an association between high-grade types of malignancy and the diffuse pattern of breast involvement. In a study of 32 cases of non-Hodgkin lymphoma of the breast, Liberman et al. (23) found that mammographic findings of diffuse increased density with skin thickening occurred in 9% of patients.
Pseudolymphoma is a benign pathologic process that resembles malignant lymphoma. In a series of five patients, the presentation of pseudolymphoma was of an enlarging breast mass that was composed of mature lymphoid cells on histologic examination (24). The mammographic manifestations of pseudolymphoma may be a thickened skin pattern (Fig. 9.15).
Benign Causes of a Thickened Skin Pattern
After therapeutic irradiation of the breast, skin thickening and edema are generally seen (Figs. 9.16,9.17,9.18). The findings are most prominent during the first 6 months after treatment and gradually decline, approaching a normal appearance in a variable time period (25,26,27). Libshitz et al. (25) found that 60% of patients treated with tylectomy and radiation therapy had returned to a normal skin thickness by 2 years and that 80% had returned by 3 years.
If a patient who has been treated with radiation develops a new onset of breast edema with skin thickening after the initial edema has resolved or decreased, the radiologist must be alerted to the possible development of recurrent carcinoma (Fig. 9.19). It is therefore very important in evaluating the mammogram of a treated patient to compare it with the series of pretreatment and posttreatment films. The clinical examination of these patients may, at times, be difficult if the breast becomes firm and fibrotic; therefore, the radiologist must be aware of any changes that may suggest recurrent disease.
Mastitis may produce focal or diffuse skin edema (Figs. 9.20 and 9.21). Typically, acute mastitis occurs in young
women and is related to lactation. Common organisms are staphylococcus and treptococcus. Other causes of mastitis are skin or nipple infections with extension into the breast or hematogenous spread of infection. The patient often has a fever and elevated white count.
Figure 9.12 HISTORY: A 56-year-old woman who is status postlumpectomy for a small invasive ductal carcinoma of the right breast. She had completed chemotherapy but had not yet begun radiation. Mammography had shown extremely dense breast tissue with no focal abnormalities.
MRI: T1-weighted postcontrast axial image (A) and subtraction image (B) show a focal irregular region of enhancement in the lateral aspect of the right breast. This lesion showed rapid washing and washout of contrast on the kinetics curves. There is also skin thickening that enhances in the right breast, particularly laterally.
IMPRESSION: Highly suspicious for residual carcinoma with possible skin involvement.
HISTOPATHOLOGY: Punch biopsy of the skin was performed showing tumor in dermal lymphatics. Subsequent mastectomy showed invasive ductal carcinoma with lymphatic involvement.
Diffuse mastitis may be associated with a breast abscess that appears as an ill-defined mass mammographically. In a review of 21 patients with a breast infection, Crowe et al. (28) found that 21% had skin thickening on mammography. Ultrasound may demonstrate a complex mass; aspiration of purulent fluid and positive cultures confirm the diagnosis. The dermal manifestations on biopsy in acute mastitis generally are prominent perivascular and periductal inflammation with or without dilated dermal lymphatics (1). Mastitis should improve soon after implementation of antibiotic therapy. If the symptoms do not clear, one should exclude inflammatory breast cancer and perform a punch biopsy of the skin.
Impaired Lymphatic Drainage
In patients with obstructed lymphatic drainage of the breast from node removal or nodal involvement with neoplasm, skin edema occurs (5). Prominence of the interstitium and thickening of the skin without an underlying mass are present mammographically (Fig. 9.22). Enlarged axillary nodes may be present when neoplastic involvement obstructs lymphatic drainage. After node removal or dissection, edema of the breast may persist mammographically and may be less obvious clinically. If an axillary node dissection is performed for
metastatic disease (i.e., melanoma) and skin thickening occurs, it is often impossible to determine on mammography if the finding represents metastatic involvement of the breast or impaired lymphatic drainage from surgery.
Figure 9.13 HISTORY: A 70-year-old woman with a history of endometrial carcinoma, presenting with a painful swollen left breast.
MAMMOGRAPHY: Left ML (A) and CC (B) views. The left breast is very dense. There is a diffuse edema pattern with a marked increase in skin thickness (arrow) and prominence of the interstitium. The primary differentials in this patient are metastatic to the breast, inflammatory breast cancer, and edema secondary to axillary adenopathy.
IMPRESSION: Edema pattern, favoring metastases to the breast from endometrial cancer.
HISTOPATHOLOGY: Endometrial cancer metastatic to the breast.
Figure 9.14 HISTORY: A 49-year-old woman with a history of melanoma, presenting with new heaviness and thickening of the left breast.
MAMMOGRAPHY: Left (A) and right MLO (B) views show marked asymmetry in the appearance of the breasts, with the left being diffusely more dense than the right. There is diffuse skin thickening over the left breast with prominence of the interstitial markings, also seen on the CC view (C). Melanoma is a tumor that metastasizes to the breast and should be considered when this mammographic pattern occurs.
IMPRESSION: Metastatic melanoma to the left breast.
HISTOPATHOLOGY: Metastatic melanoma involving breast, skin, and subcutaneous tissue.
Figure 9.15 HISTORY: An 81-year-old woman with a right parotid gland mass and a right breast mass.
MAMMOGRAPHY: Bilateral MLO (A) and CC (B) views. There is generalized asymmetry between the breasts. The right breast is more dense, and there is a prominence of interstitial markings. There is slight skin thickening inferiorly. With the history of parotid gland tumor, one might consider metastatic disease to the breast or lymphoma or pseudolymphoma as high in the differential diagnosis.
HISTOPATHOLOGY: Lymphocytic infiltration of the breast (lymphoma found in the parotid gland). (Case courtesy of
Dr. Melvin Vinik, Richmond, VA.
Figure 9.16 HISTORY: A 64-year-old woman who is 2 years status postlumpectomy and breast irradiation for invasive ductal carcinoma.
MAMMOGRAPHY: Left MLO (A) and CC (B) views show a postsurgical scar appearing as an area of architectural distortion in the 12 o'clock position. Diffuse skin thickening and trabecular thickening are present, as well as focal skin thickening and retraction (arrow)at the lumpectomy site, seen best on the magnification MLO view (C). These changes were less prominent than on the prior posttreatment studies.
IMPRESSION: Edema pattern secondary to radiation therapy.
Figure 9.17 HISTORY: A 65-year-old woman 6 months after lumpectomy and radiotherapy for ductal carcinoma in situ in the left upper-outer quadrant.
MAMMOGRAPHY: Bilateral MLO views (A) and bilateral CC views (B). There is diffuse increased density with interstitial edema involving the left breast. Surgical clips in the upper outer quadrant mark the lumpectomy site. Skin thickening is present (arrow)diffusely on the treated side. The diffuse changes are related to radiotherapy and are maximum on this study. The edema gradually decreases over time and approaches a normal skin thickness and breast density.
IMPRESSION: Skin thickening and interstitial thickening secondary to radiotherapy.
Figure 9.18 HISTORY: A 63-year-old woman status post-lumpectomy and radiation therapy for right breast cancer.
MAMMOGRAPHY: Bilateral MLO (A) and CC (B) views show a scar marker at the lumpectomy site. There is architectural distortion at the site, consistent with scar. Diffuse and focal skin thickening is present, related to the surgical scarring and the radiation effect. On the magnification view (C), the architectural distortion is evident (arrow).
IMPRESSION: Normal postlumpectomy and radiation changes.
Figure 9.19 HISTORY: A 55-year-old woman who, in March 1982, had lumpectomy and radiation therapy for a carcinoma in the lower inner quadrant of the left breast. In 1985, she returned with an increase in thickness of the left breast.
MAMMOGRAPHY: Left ML (A) and CC (B) views in 1982 and left MLO view in 1985 (C). Three months after treatment, there is increased density of the trabeculae with mild skin thickening. There is focal increased density remaining at the lumpectomy site, presumed to be related to resolving hematoma. Three years later, on the left MLO view (C), there is marked skin thickening with greater density of the breast diffusely near the chest wall.
IMPRESSION: Recurrent carcinoma after lumpectomy and radiation therapy.
HISTOPATHOLOGY: Infiltrating ductal carcinoma.
NOTE: The skin thickening and edema of the breast that occur after radiation therapy are greater in the months immediately following treatment, and the changes gradually resolve over several years. The development of new skin thickening should alert the radiologist to the possible development of recurrent carcinoma. When the treated breast is being evaluated, it is very important to review the entire series of mammograms after treatment for subtle changes in skin thickness or parenchymal density.
Figure 9.20 HISTORY: A 26-year-old woman who is 7 months pregnant and who presents with a painful, swollen, tender left breast. Clinical examination showed mild erythema in the periareolar area with mild skin thickening in this region.
MAMMOGRAPHY: Bilateral MLO (A) views show a mild degree of skin thickening, primarily in the left periareolar area. No underlying mass or calcifications were present. Sonography (B) showed thickening of the skin as well as edema in the subcutaneous tissue.
MANAGEMENT: The patient was treated with oral antibiotics and improved symptomatically. Follow-up clinical examination and ultrasound showed resolution of the edematous changes. It is important to follow a possible mastitis to complete resolution, often also with follow-up imaging, to assure that malignancy is not present.
Figure 9.21 HISTORY: A 52-year-old gravida 4, para 4 woman presenting with fever, chills, and a large hard mass in the left breast.
MAMMOGRAPHY: Bilateral MLO (A) and CC (B) views. There is marked asymmetry in the appearance of the breasts. The left breast is diffusely dense with prominent interstitial markings. The left breast appears smaller than the right because of the thickening present and the lesser degree of compressibility of the tissue. Enlarged nodes are present in the left axilla. The differential diagnosis includes primarily acute mastitis versus inflammatory breast cancer. The extensive nature of the process is suspicious for neoplasm, but because of the patient's constitutional symptoms, mastitis is more likely.
HISTOPATHOLOGY: Fat necrosis, acute inflammation, abscess.
NOTE: The patient was treated with antibiotics, and the clinical examination returned to normal.
Figure 9.22 HISTORY: An 82-year-old gravida 1, para 1 woman with a history of melanoma. Clinical examination showed enlarged tender lymph nodes in the axilla and firmness diffusely throughout the left breast.
MAMMOGRAPHY: Bilateral CC views. Marked asymmetry in the appearance of the breasts is noted. There is diffuse increase in the density of the interstitium of the left breast with marked skin thickening (arrow). Skin thickening in a patient with a history of melanoma could represent diffuse metastatic involvement of the breast with melanoma or edema secondary to lymphatic obstruction from axillary adenopathy. (Biopsy of the breast and axillary dissection were performed).
HISTOPATHOLOGY: Metastatic melanoma in 38 of 40 lymph nodes with no involvement of the breast.
Figure 9.23 HISTORY: An 82-year-old gravida 5, para 5 woman with severe breast trauma to the right breast 6 months earlier, presenting with a right breast mass, which was unchanged in size since the trauma.
MAMMOGRAPHY: Bilateral CC (A) and right MLO (B) views. There is marked asymmetry in the appearance of the breasts (A), with the right being diffusely more dense than the left. Prominence of the interstitium is present on the right (A and B), but no significant skin thickening is noted. Given the clinical history, this finding is most consistent with a diffuse interstitial hematoma with fat necrosis. The time for resolution of a hematoma is variable, and late changes of fat necrosis may be palpated as a firm mass.
IMPRESSION: Interstitial hematoma with fat necrosis.
NOTE: The breast was biopsied because of clinical concern about the palpable finding, and the biopsy showed fat necrosis.
Sometimes lumpectomy or surgery that involves the upper outer quadrant or the axillary tail can also produce a mild degree of chronic breast edema. This condition is related to impaired lymph drainage caused by transection of lymphatic channels in the upper outer quadrant. The edematous changes may be evident clinically and mammographically.
Fat necrosis and interstitial hematoma of the breast may produce focal or diffuse skin thickening. Generally, the edema is focal unless the trauma is severe or the hemorrhage is extensive (Fig. 9.23). Clinical history is key in suggesting the diagnosis, because posttraumatic changes with skin involvement may have an identical appearance with that of locally advanced breast cancer. Patients who have been treated with Coumadin for thromboembolic disorders may develop acute breast necrosis, appearing mammographically as an edema pattern (29). Burns to the chest area with scarring can also produce prominent skin thickening of a chronic nature, and this is usually not associated with interstitial thickening (Figs. 9.24 and 9.25). There may be distortion of the normal breast contour because of contractures.
Figure 9.24 HISTORY: A 36-year-old gravida 4, para 4 woman who had suffered burns to the anterior chest area years ago, for screening mammography.
MAMMOGRAPHY: Bilateral CC (A) and MLO (B) views. There is distortion of the contour of the breasts bilaterally, with retraction centrally. Skin thickening (arrows) (A) is present bilaterally, consistent with scarring from the burns. Coarse dystrophic skin calcification, probably secondary to the scarring, is present on the right (arrowhead) (B). Incidental note is made of a well-defined nodule in the left upper-outer quadrant, which was found to be cystic on ultrasound.
IMPRESSION: Skin thickening secondary to a burn injury.
Systemic conditions that produce a fluid overload state are manifested in the breast as bilateral diffuse skin thickening (Figs. 9.26,9.27,9.28,9.29,9.30). Cardiac failure, renal failure, cirrhosis, and hypoalbuminemia are other benign causes of a thickened skin syndrome (5). In these patients, the breasts may feel heavy, and there is edema noted on clinical examination with a peau d'orange
appearance. However, the breasts are usually not8 erythematous or tender, and no mass is palpable. The thickening occurs mostly in the dependent aspect of the breast. If the patient has been lying on one side, the edema is unilateral in the dependent breast (30).
Figure 9.25 HISTORY: A 70-year-old woman with a history of benign breast biopsies for screening mammography.
MAMMOGRAPHY: Bilateral MLO (A) and CC (B) views show very-well-defined densities bilaterally, marked with wires indicating the biopsy sites. These densities have very defined edges, suggesting that the lesions are on the skin and are demarcated by an air halo. Clinical examination confirmed keloids.
IMPRESSION: Keloids at biopsy sites causing focal skin thickening.
Figure 9.26 HISTORY: An 81-year-old woman with thickening of the left breast and no focal palpable mass.
MAMMOGRAPHY: Left MLO (A) and right MLO (B) views. There is bilateral skin thickening, worse on the left (A) than on the right (B). A diffuse edema pattern is noted with thickening of the interstitial markings of the breasts. Incidental note is made of a small lipoma(arrow) in the right breast. The differential diagnosis for bilateral asymmetric skin thickening includes systemic causes, such as fluid overload states, congestive heart failure, renal failure, metastatic disease to the breast, and hemorrhage secondary to anticoagulant therapy.
IMPRESSION: Congestive heart failure producing an edema pattern in the breasts.
NOTE: The patient had been lying on the left side, presumably accounting for the asymmetric edema on the left.
Figure 9.27 HISTORY: A 75-year-old woman for screening mammography. She has a history of chronic renal failure secondary to an allergic reaction to penicillin.
MAMMOGRAPHY: Bilateral MLO views (A) and bilateral MLO views before the onset of renal failure (B). The breasts show a symmetrical edema pattern (A) characterized by increased interstitial markings and skin thickening. These findings were not present on the baseline mammogram (B). Diffuse bilateral edema suggests a systemic origin and in this case is secondary to renal failure. There is a fluid overload state and an increase in thickness of the interstitium by this fluid filling.
IMPRESSION: Edema pattern secondary to renal failure. (Case courtesy of
Dr. Cherie Scheer, Richmond, VA.
Figure 9.28 HISTORY: A 43-year-old woman with end-stage renal disease.
MAMMOGRAPHY: Bilateral MLO (A) and CC (B) views show marked increased density of both breasts. There is an edema pattern with marked skin thickening (arrows) and trabecular thickening. The thickness of the skin exceeds 10 mm bilaterally. Extensive arterial and punctuate calcifications are present bilaterally, associated with the renal failure and hypercalcemic state.
IMPRESSION: Edema pattern and arterial calcifications consistent with renal failure and fluid overload.
Figure 9.29 HISTORY: A 54-year-old woman with a history of renal disease, for screening mammography.
MAMMOGRAPHY: Bilateral MLO (A) and CC (B) views show extensive vascular calcifications in both breasts and a marked edema pattern. There is skin thickening and trabecular thickening diffusely and bilaterally, suggesting a systemic etiology.
IMPRESSION: Edema pattern and vascular calcifications consistent with renal disease and fluid overload.
The range of normal skin thickness varies from patient to patient, with the inferior and medial aspects of the breasts being thicker. When skin thickening is present, whether focally or diffusely, mammography and physical examination are important to the radiologist in suggesting the probable cause. Unilateral edema is caused by impairment of lymph drainage, as seen in mastitis, postradiation change, axillary lymphatic obstruction, and inflammatory carcinoma. A bilateral edema pattern suggests a systemic etiology, such as congestive heart failure or renal failure.
Other image modalities, such as ultrasound and MRI, are particularly helpful in the patient with unilateral edema of unknown etiology. These may identify a suspicious mass in the patient with inflammatory carcinoma when the edema obscures the mass on mammography. If mastitis is suspected, treatment with antibiotics is performed, with immediate follow-up mammography and physical examination to assure complete resolution of the edema. The persistence of symptoms after 2 weeks should prompt biopsy of the skin to exclude inflammatory carcinoma.
In patients with bilateral edema, clinical examination and medical history are most helpful in identifying the etiology. In these patients with systemic causes of edema, mammography alone and no other imaging modalities are usually necessary to evaluate the breasts.
Figure 9.30 HISTORY: Elderly patient with a history of cardiac insufficiency, for screening mammography. Clinical examination showed mild pitting edema of the breasts with no erythema.
MAMMOGRAPHY: Left MLO (A) and left CC (B) and right CC (C) views show marked trabecular and skin thickening bilaterally, consistent with an edema pattern. There are also extensive vascular calcifications bilaterally.
IMPRESSION: Edema pattern secondary to congestive heart failure.