Paula J. Adams Hillard
A pelvic mass can be identified during a routine screening examination, or it can be discovered during an evaluation for abdominopelvic pain or abnormal bleeding. The list of likely diagnoses of a pelvic mass for prepubertal and adolescent females is different than that for older women, although there may be some overlap (Hillard, 2002). For example, an imperforate hymen causing severe cyclic abdominal pain and a large pelvic mass are more likely to present in a 14-year-old girl than in a 34-year-old woman. Germ cell tumors of the ovary are more common in teens than epithelial carcinoma. Uterine masses such as uterine fibroids are not common in adolescents but are quite common among adult women. Table53.1 lists a number of conditions that may be diagnosed as a pelvic mass in women of reproductive age.
Anatomical genital anomalies are rare, but they can have profound implications for future reproductive capability in teens (Spence, 1998). Many of these can present as pelvic masses.
Uterine Defects: Incomplete Fusion
The uterus is formed by fusion of paramesonephric ducts in the midline. If lateral fusion is incomplete, then a uterine didelphys may form with two separate uterine halves (each with its own cervix, corpus-attached fallopian tube and ovary, and possibly vaginal canal). This diagnosis may be suspected when menstrual flow cannot be controlled with a tampon. On examination, one of the two uteri may be mistaken for an adnexal mass. If uterine fusion is partial, there may be a bicornuate uterus or blind uterine horn. If functional endometrium is present within this obstructed horn, severe cyclic pain can occur (Kim and Laufer, 1994). The diagnosis can be suggested on the basis of a screening pelvic ultrasound examination. If a developmental anomaly is suspected on ultrasound examination, magnetic resonance imaging (MRI) is the best technique for clarifying genital anomalies, although laparoscopy may be required to delineate anatomical structures adequately Economy et al., 2002). If fusion is complete but the resorption of the midline is incomplete, a septate uterus can result. Renal and skeletal anomalies are common in conjunction with uterine fusion defects.
Vaginal Defects: Incomplete Fusion
The vagina also forms in two parts, and defects typically occur as a result of failure of longitudinal fusion or
canalization. The upper approximate three fourths form from the inferior portion of the fused paramesonephric ducts and the lower one fourth from the sinovaginal bulbs. The lowest portion of these bulbs fills with a solid core of tissue called the vaginal plate. If the upper and lower vaginal portions do not fuse, then a transverse vaginal septum forms. Similarly, if the solid core of tissue at the junction of the vaginal plate and the urogenital sinus do not canalize completely, the woman can have an imperforate hymen or vaginal agenesis. If a uterus with functional endometrium is present along with a transverse vaginal septum or imperforate hymen, menstrual fluid accumulates within the patent portion of the vagina (hematocolpos) and within the uterus (hematometra), which then presents as a “pelvic mass”(Kim and Laufer, 1994).
Women with uterovaginal agenesis—Mayer-Rokitansky-Küster-Hauser syndrome—may have uterine remnants that may or may not contain functioning endometrium that can cause pain and a mass that is diagnosed with ultrasonography or MRI.
Müllerian Duct Remnants
Another class of anatomical congenital anomalies that can create pelvic masses arises from remnants of the mesonephric/müllerian duct system or mesovarium that should have degenerated in utero in the presence of antimüllerian hormone. At least 25% of women have small remnants of these systems. These remnants can present in the lateral adnexa as paraovarian cysts or paratubal cysts. They are often multiple and can vary in size from <1 cm to 20 cm. Along the lateral wall of the vagina or uterus, these remnants present as Gartner duct cysts. These müllerian remnants are rarely symptomatic; however, torsion can occur, and persistent larger masses may be confused with an ovarian neoplasm.
Urachal Cysts and Pelvic Kidneys
Urachal cysts, although rare, can be found along the midline above the bladder and can be confused with other pelvic masses. A pelvic kidney must also be included in the differential diagnosis, particularly in a young woman who has not undergone previous pelvic or renal imaging. Any other structure in the pelvis, such as a full bladder or hard stool in the bowel, can be confused with a pelvic mass.
Pregnancy Presenting as Pelvic Mass
The possibility of an intrauterine pregnancy enlarging the uterus or an ectopic pregnancy (see Chapter 56) causing an adnexal mass must be considered in the differential diagnosis of every young woman with secondary sexual characteristics. A sensitive urine pregnancy test can reliably rule out a clinically significant pregnancy. However, in many instances the test is not ordered because the provider does not consider it likely that the young woman has been sexually active. Adolescents may be unwilling or unable to disclose their history of sexual activity for a variety of reasons—they may fear disappointing their parents or the clinician; they may have insufficient knowledge or awareness of pregnancy-related symptoms; they may deny the possibility of pregnancy; the clinician may not have established or discussed provisions of confidentiality; or the question may not have been asked in a sensitive manner in a private setting. Currently, it is recognized that both sexual abuse and early consensual sexual activity occur at surprisingly high rates. If pregnancy testing is a routine order, then its use in any individual case does not require justification. The consequences of missing a pregnancy-related cause of pain, bleeding, or asymptomatic pelvic mass justify routine pregnancy testing in all young women presenting with pain, amenorrhea, abnormal bleeding, or a pelvic mass (Adams Hillard and Deitch, 2005).
Infection as a Cause of a Pelvic Mass
As the rates of sexually transmitted diseases (particularly chlamydia) have increased among adolescents, the incidence of upper track involvement with salpingitis or pelvic abscess (tuboovarian abscess [TOA]) has also increased (see Chapter 63). The U.S. Centers for Disease Control and Prevention (CDC) estimates that adolescents have the highest age-specific rates for chlamydia and gonorrhea, and therefore high rates of pelvic inflammatory disease (PID) (Centers for Disease Control and Prevention, 2002). Gonococcal PID has classic signs and symptoms and is relatively easy to diagnose clinically. However, chlamydia PID is more subtle in its presentation. Usually, Chlamydia trachomatis elaborates a heat shock protein that silently destroys the cilia lining the fallopian tube with only minimal symptomology. If the tissues become secondarily infected with enteric organisms, a clinically apparent salpingitis can develop. In the acute stage, pelvic infection is often accompanied by fever, cervical discharge, motion tenderness, and possibly adnexal masses (pyosalpinges or TOAs). After resolution of the acute infection, the tubes may remain dilated and filled with fluid (hydrosalpinges), particularly if their fimbriae have been sealed. Treated pelvic abscesses may also cause palpable masses due to adhesions—pelvic scarring with matting or agglutination of bowel, ovary, fallopian tube, and other structures. Other infectious causes of pelvic masses include an appendiceal abscess or (rarely in young girls) diverticulitis or Meckel diverticulum.
Adnexal torsion involves the acute rotation of adnexal structures. Torsion of the normal adnexa can occur, particularly in prepubertal girls; however, torsion is more likely to occur when an adnexal mass—a benign ovarian neoplasm, functional ovarian cyst, or a paratubal cyst—rotates around its vascular pedicle. Once rotated, the venous flow to the mass is obstructed while arterial flow continues, inflating the mass until arterial flow is compressed. The adnexal structures become edematous and ultimately gangrenous.
Women usually experience bouts of intense pelvic pain, which may be accompanied by nausea and vomiting. Findings on examination include peritoneal signs with rebound tenderness.
Typical findings on ultrasound examination with Doppler flow studies include the presence of a mass, edema, adnexal asymmetry, and absent venous and/or arterial flow; unfortunately, these findings are neither perfectly sensitive nor specific, and clinical judgment must be used, including a high index of suspicion (Breech and Hillard, 2005). Spiraling or whirlpool configuration of the vessels may be seen and is a more specific finding. Consultation with a gynecologist is essential, as adnexal torsion is a surgical emergency.
Treatment consists of untwisting the adnexae, even if hemorrhage and apparent necrosis are present. This can usually be performed laparoscopically. Excision of the cyst can be delayed and performed as an interval procedure once edema has resolved. Attempts to remove the cyst acutely may fail because of the marked edema that is typically present. Every attempt should be made to preserve the involved ovary.
In adolescent women, uterine neoplasms are quite rare. Leiomyomas (fibroids) develop within the wall of the uterus (intramural myomas) and later extend toward the endometrium (submucosal myomas) or toward the external surface of the myometrium (subserosal myomas). Although fibroids are extremely common in adult women, occurring in up to 50% of women older than 35, they are rare in adolescents. Although fibroids are frequently asymptomatic in adults, adolescents presenting with abnormal bleeding or pelvic pain may have demonstrable fibroids palpable on examination or demonstrated on pelvic ultrasonography.
Benign Ovarian Masses
Benign ovarian masses include functional ovarian cysts, endometriomas, and benign ovarian neoplasms. Whenever an ovarian mass is diagnosed in an adolescent female or prepubertal child, every effort must be made to preserve the reproductive function in that female in order to ensure future childbearing—whether the mass is physiological or neoplastic, benign or malignant (Kozlowski, 1999). Table 53.2 lists benign ovarian tumors. Figure 53.1 provides a plan for management of pelvic masses in premenarchal and adolescent girls.
Physiological (Functional) Ovarian Cysts
Functional ovarian cysts include follicular cysts, corpus luteum cysts(CLCs), and theca lutein cysts. All are benign and usually do not cause symptoms or require surgical management. Cigarette smoking has been associated with an increased risk of functional cysts (Holt et al., 1994). Functional cysts result from expansion of the cavity of a preovulatory follicle (follicular cyst) or corpus luteum (CLCs), and are associated with the disordered function of the pituitary-ovarian axis. The incidence of functional ovarian cysts in adolescents is not well established, but most are asymptomatic, and they are frequently an incidental finding on pelvic imaging. One study, in which adolescents were followed up for 1 year with monthly serial ultrasound studies, found ovarian cysts in 12% of those observed (Porcu et al., 1994). Theca lutein cysts—the least common type of functional cyst—result from human chorionic gonadotropin (hCG) stimulation, producing bilateral follicular cystic ovarian enlargement. They occur in patients with gestational trophoblastic disease (molar pregnancies and choriocarcinoma) and multiple pregnancies and regress with the removal of the pregnancy-associated hCG production.
Kanizsai et al., 1998). Persistent ovarian masses are more likely to be neoplastic and should prompt a referral for consideration of surgical excision (Spanos, 1973). Decisions about whether surgical excision of ovarian masses is required are best made by gynecological surgeons who have experience with adolescent and pediatric patients. Decisions about the type of surgical intervention are guided by the suspicion of malignancy; in general, benign-appearing masses can usually be managed using operative laparoscopy, while masses suspicious for malignancy require laparotomy (Mane and Penketh 1999; Parker and Berek 1994).
Because oral contraceptives suppress ovulation and follicular development, they reduce the risk of CLCs and follicular cysts in a dose-dependent manner (Grimes et al., 1994). DMPA also reduces the risk of functional ovarian cyst formation. Administration of oral contraceptives to induce cyst regression is no more effective than an observation period with no hormonal therapy, although it will suppress the development of subsequent functional cysts (Steinkampf et al., 1990).
Although transvaginal ultrasonography is useful in demonstrating these findings—multiple (>10–12) small follicles <1 cm in diameter—this technique may be problematic in young or virginal adolescents. In addition, studies have suggested that up to 25% of women may have such ovarian morphology without the other diagnostic criteria. The volume of the ovary may be increased by a factor of 2 to 3, not only by the presence of these follicles but also by an increase in the ovarian stroma; this ovarian enlargement may be unilateral or bilateral. Although PCOS does not cause pain and this is not a condition that requires surgical management when the ultrasonographic characteristics are noted, clinical evaluation is appropriate to minimize the morbidity and improve quality of life. The lifelong metabolic implications of the condition should prompt management with lifestyle modification. Oral contraceptives and/or insulin-sensitizing agents can be helpful in management.
FIGURE 53.1 Management of pelvic masses in premenarchal and adolescent girls. AFP, α-fetoprotein; hCG, human chorionic gonadotropin.
Endometriomas and Endometriosis
Endometriosis is a condition in which ectopic endometrium is present outside of the uterus. The presence of ovarian endometriosis can result in the formation of an ovarian endometrioma. There is a broad range of ultrasound appearances of endometriomas—diffuse, low level internal echoes occur in most endometriomas, and hyperechoic wall foci and multilocularity also suggest the diagnosis of an endometrioma.
Endometriosis has historically been considered to be a condition affecting adult women; however, it is receiving increasing recognition as a cause of pelvic pain in adolescents (American College of Obstetricians and Gynecologists, 2005). Although the prevalence of endometriosis in adolescents is not well established, there is a familial incidence, and endometriosis can be demonstrated in up to 40% to 50% of adolescents undergoing laparoscopy because of chronic pelvic pain unresponsive to the use of hormonal manipulation, such as oral contraceptives and nonsteroidal anti-inflammatory drugs (NSAIDs). Endometriomas are also rare in adolescents, who typically have early stage or mild disease.
Because laparoscopy is indicated for diagnosing and managing suspected endometriosis in adolescents, adolescents with pelvic pain or dysmenorrhea that is unresponsive to NSAIDs and oral contraceptives should be referred to a gynecologist for consideration of surgical confirmation before medical therapy.
Benign Ovarian Neoplasms
The ultrasonographic characteristics of an ovarian mass will dictate the management. Adolescents with persistent cystic ovarian masses on ultrasonography following 6 to 8 weeks of observation may have an ovarian neoplasm and should be referred to a gynecologist for surgical management. Because benign cystic teratomas (dermoid cysts) are the most common ovarian neoplasm in adolescents, an adolescent with an ultrasonogram showing characteristics suspicious of this tumor should also be referred for gynecological surgical evaluation. Solid masses of any size are suspicious for a malignant tumor, and should lead to prompt referral.
Benign Germ Cell Tumors
Benign cystic teratomas (dermoid cysts) are the most common benign ovarian neoplasm of adolescent and reproductive years (Koonings et al., 1989). Dermoid cysts are composed of all three germ cell layers. They are generally thick-walled cysts and may be filled with sebaceous material, hair; they may also contain cartilage, teeth, or other tissues such as thyroid. These embryological elements produce characteristic findings on ultrasonography that can suggest the likelihood of a benign cystic teratoma (Patel et al., 1998). Malignant transformation occurs in less than 2% of dermoid cysts in women of all ages and is rare in adolescents. Dermoid cysts vary in size from millimeters to quite large, but the vast majority is smaller than 10 cm. On examination, they are unilateral (only 10% are bilateral), very mobile, anteriorly positioned (fat floats), nontender adnexal masses. Benign cystic teratomas are usually asymptomatic. The risk of torsion with dermoid cysts is approximately 15%, and it occurs more frequently with ovarian tumors in general, perhaps because of the high fat content of most dermoid cysts, allowing them to float within the abdominal and pelvic cavity (Templeman et al., 2000a). An ovarian cystectomy is almost always possible, even if it appears that only a small amount of ovarian tissue remains. Preserving a small amount of ovarian cortex in a young patient with a benign lesion is preferable to the loss of the entire ovary (Templeman et al., 2000b). Laparoscopic cystectomy is usually possible, and intraoperative spill of tumor contents is rarely a cause of complications (Lin et al., 1995). Laparoscopy results in lower operative morbidity, as well as less postoperative pain and analgesic requirements, and a shorter hospital stay and recovery period when compared with laparotomy (Yuen et al., 1997). Adolescents with ultrasonography suggesting a dermoid should be referred to a gynecological surgeon skilled in laparoscopic surgery, who appreciates the importance of ovarian conservation.
Benign Epithelial Neoplasia
Serous or mucinous cystadenomas account for 10% to 20% of benign ovarian neoplasms in female adolescents. These tumors are multiloculated, fluid-filled cystic masses. Serous cystadenomas may not be recognized as a neoplasm; cyst aspiration without removal of the entire cyst (including multiple loculated areas and cyst wall) may result in recurrence. Benign mucinous cystadenomas have smooth, lobulated surfaces with multiloculations filled with viscous mucoid material; these masses
can reach very large dimensions. Surgical removal of these adenomas is necessary for tissue diagnosis and to prevent symptoms from an enlarging mass or torsion.
Sex Cord-Stromal Tumors
Overall, these tumors are relatively rare, but they occur with higher prevalence in premenarchal girls than in adolescents or adults, and comprise 10% to 20% of childhood ovarian tumors. They may be hormonally active. Granulosa cell tumors and theca cell tumors produce estrogen whereas Sertoli-Leydig cell tumors produce androgens with or without estrogen. As a result of this sex-steroid production, sex cord-stromal tumors can cause precocious puberty, menstrual abnormalities, endometrial hyperplasia or carcinoma, or hirsutism, acne, and virilization. These signs should prompt pelvic imaging for diagnosis. Pure granulosa cell tumors are highly malignant, whereas mixed tumors behave less aggressively. Prognosis is excellent with unilateral salpingo-oophorectomy and appropriate surgical staging for the 95% of tumors that are unilateral.
Malignant Ovarian Masses
Ovarian cancer is rare in adolescents and younger girls. Only slightly more than 1% of all ovarian cancers occur in women younger than 20 (Young et al., 2003). Ultrasound features of an ovarian mass that are a cause of concern for malignancy include solid consistency, large size, complex appearance (not entirely cystic), internal loculations, internal or external excrescences, and ascites (Stepanian and Cohn, 2004). Efforts to preserve fertility are important considerations in the management of ovarian malignancies in adolescents.
Malignant Germ Cell Tumors
In women younger than 20 years, one half to two thirds of all ovarian tumors are of germ cell origin and one third of those tumors are malignant. Malignant germ cell tumors include dysgerminoma, mixed germ cell tumor, endodermal sinus tumor, immature teratoma, embryonal tumor, choriocarcinoma, and polyembryoma. Because some ovarian neoplasms secrete protein tumor markers, including α-fetoprotein (AFP), hCG, carcinoembryonic antigen (CEA), lactate dehydrogenase (LDH), and others, measurement of these substances can be considered in making a diagnosis of an ovarian tumor and in following up malignant tumors for recurrence and clinical response (Kawai et al., 1992). CA-125 is a tumor marker for epithelial ovarian cancer, and while useful in evaluating adnexal masses in postmenopausal women it is not very specific, and in adolescents and premenopausal women it may be elevated with endometriosis, PID, pregnancy, Crohn disease, and other abdominal malignancies. Decisions about whether to obtain tumor markers before surgery should be made in consultation with a gynecologist or gynecological oncologist. Measurement of estradiol and testosterone can be helpful in evaluating and following up hormonally active tumors.
Dysgerminomas comprise 50% of all ovarian germ cell malignancies. They represent abnormal proliferations of the undifferentiated germ cell. Five percent to 10% of these tumors occur in phenotypically female patients with gonadal dysgenesis (e.g., pure gonadal dysgenesis—46, XY; mixed gonadal dysgenesis 45X/46/XY; or complete androgen insensitivity syndrome—46, XY). Dysgerminomas have also been reported in girls with Turner syndrome. Because the presence of a Y chromosome or antigen is associated with a high risk of malignancy, bilateral gonadectomy is recommended. With androgen insensitivity syndrome, the risk of malignancy is low before puberty, and therefore the gonads should be removed after pubertal development is complete. Dysgerminomas are more likely to be bilateral than other germ cell tumors.
Immature teratomas represent 10% to 20% of all ovarian malignancies in women younger than 20 years. Approximately half of all pure immature teratomas occur in adolescent females. Premenarchal and younger age is associated with a greater risk of an immature malignant teratoma (Azizkhan and Caty 1996). Immature teratomas contain elements that resemble tissues derived from the embryo that do not mature. The amount of immature neural tissue is most predictive of lethality. Surgical staging and histological grade determine survival rates. Surgery alone is curative for most children and adolescents with completely resected ovarian immature teratoma (Cushing et al., 1999).
Endodermal sinus tumors (“yolk sac tumors”) of the ovary are rare. Most (70%) patients present with abdominal or pelvic pain, and these tumors have an aggressive clinical course, and therefore chemotherapy is indicated (Stepanian and Cohn 2004). Most of these tumors secrete tumor markers such as α-fetoprotein (AFP).
Malignant Epithelial Tumors
Although these tumor types are the most common type of ovarian malignancy in adult women, they rarely develop in adolescents (Richardson et al., 1985). Included in this group of neoplasias are serous cystadenocarcinoma, mucinous cystadenocarcinoma, and endometrial cystadenocarcinoma. In adolescents, approximately 7% of epithelial tumors will be borderline malignancies, which can be managed with conservative surgery (unilateral salpingo-oophorectomy), careful assessment of the contralateral ovary, and appropriate staging procedures. Often, the borderline characteristics are diagnosed on permanent section pathological examination of a mass that was initially felt to be benign. Consultation and management in conjunction with a gynecological oncologist is appropriate in this situation, as recurrences may occur many years later. Less than 5% of ovarian epithelial tumors in adolescents are invasive malignancies. In these patients, appropriate surgical staging, cytoreductive surgery, and chemotherapy are required, as in adults; conservative management in early stage disease may allow the preservation of fertility. These patients require ongoing management by a gynecological oncologist.
Genetic Risk of Epithelial Ovarian Cancers
Approximately 5% of ovarian cancer before 70 years of age is associated with the genetic mutations in the breast cancer gene 1 (BRCA-1). Presence of this gene confers an increased risk of ovarian and breast cancer. Families with multiple family members with breast and/or ovarian cancer should be offered referral to specific familial cancer centers, which are present in many medical centers around the country. Decision making around these
issues is challenging, and clinicians must balance providing information to families and adolescent patients, facilitating decision making, and minimizing family members' anxiety. Although the optimal age at which genetic testing should be performed has not been well established, many clinicians recommend offering counseling and testing in young adulthood (Laufer and Goldstein, 2005).
In young women, the more common metastatic lesions of the ovary include lymphomas and leukemias.
Minimizing the Risks of Ovarian Masses and Malignancies
Oral contraceptive pills minimize the risks of functional ovarian masses in a dose-dependent manner (Grimes et al., 1994). Because they consistently prevent ovulation, CLCs are minimized. Ultra-low-dose estrogen–containing oral contraceptive pills as well as oral contraceptives containing higher doses of estrogen may not prevent follicular cysts.
Adolescents who have had an oophorectomy, an ovarian cystectomy, or an ovarian neoplasm may particularly benefit from the use of oral contraceptive pills to minimize the risks of developing a subsequent functional cyst (Muram et al., 1990). Oral contraceptives minimize the risks that a functional cyst will leave a sole-remaining ovary vulnerable to surgical extirpation. In adolescents with a previous malignancy who are being monitored for recurrence, the development of a functional cyst will almost invariably lead to patient and parental anxiety, additional diagnostic testing, and even potential surgical exploration. Therefore, suppression of ovarian functional cysts can be particularly beneficial.
Combination oral contraceptives are associated with a 30% to 60% reduction in the risk of epithelial ovarian malignancies (Grimes and Economy, 1995). Preventing ovarian cancer is seldom a motivating factor for adolescents, although when combined with the contraceptive and other noncontraceptive benefits of oral contraceptives, such as decreased acne, dysmenorrhea, menorrhagia, and ovarian cysts, this benefit may provide additional motivation for ongoing oral contraceptive use to teens and their families.
For Teenagers and Parents
http://www.nlm.nih.gov/medlineplus/ency/article/001504.htm. National Institutes of Health site with references and links on ovarian cysts.
http://familydoctor.org/handouts/279.html. American Academy of Family Physicians handout on ovarian cysts.
http://www.4women.gov/faq/ovarian cysts.pdf. The National Women's Health Information Center. U.S. Department of Health and Human Services, Office on Women's Health.
http://www.goaskalice.columbia.edu/0724.html. Go Ask Alice information on ovarian cysts from the Columbia University Student Health Center.
For Health Professionals
http://www.emedicine.com/emerg/topic352.htm. E-medicine site about ovarian cysts.
References and Additional Readings
Adams Hillard PJ, Deitch HR. Menstrual disorders in the college age female. Pediatr Clin North Am 2005;52:179.
American College of Obstetricians and Gynecologists. ACOG Committee Opinion #310: endometriosis in adolescents. Obstet Gynecol 2005;105:921
Azizkhan RG, Caty MG. Teratomas in childhood. Curr Opin Pediatr 1996;8:287.
Breech LL, Hillard PJ. Adnexal torsion in pediatric and adolescent girls. Curr Opin Obstet Gynecol 2005;17:483.
Centers for Disease Control and Prevention. Sexually transmitted diseases treatment guidelines 2002. MMWR Recomm Rep 2002;51:1.
Christensen JT, Boldsen JL, Westergaard JG. Functional ovarian cysts in premenopausal and gynecologically healthy women. Contraception 2002;66:153.
Cushing B, Giller R, Ablin A, et al. Surgical resection alone is effective treatment for ovarian immature teratoma in children and adolescents: a report of the pediatric oncology group and the children's cancer group. Am J Obstet Gynecol 1999; 181:353.
Economy KE, Barnewolt C, Laufer MR. A comparison of MRI and laparoscopy in detecting pelvic structures in cases of vaginal agenesis. J Pediatr Adolesc Gynecol 2002;15:101.
Grimes DA, Economy KE. Primary prevention of gynecologic cancers. Am J Obstet Gynecol 1995;172:227.
Grimes DA, Godwin AJ, Rubin A, et al. Ovulation and follicular development associated with three low-dose oral contraceptives: a randomized controlled trial. Obstet Gynecol1994;83:29.
Helmrath MA, Shin CE, Warner BW. Ovarian cysts in the pediatric population. Semin Pediatr Surg 1998;7:19.
Hillard PA. Benign diseases of the female reproductive tract: symptoms and signs. In: Berek JS, Adashi EY, Hillard PA, eds. Novak's gynecology, 13th ed. Philadelphia, PA: Lippincott Williams & Wilkins; 2002:351.
Holt VL, Daling JR, McKnight B, et al. Cigarette smoking and functional ovarian cysts. Am J Epidemiol 1994;139:781.
Kanizsai B, Orley J, Szigetvari I, et al. Ovarian cysts in children and adolescents: their occurrence, behavior, and management. J Pediatr Adolesc Gynecol 1998;11:85.
Kawai M, Kano T, Kikkawa F, et al. Seven tumor markers in benign and malignant germ cell tumors of the ovary. Gynecol Oncol 1992;45:248.
Kim HH, Laufer MR. Developmental abnormalities of the female reproductive tract. Curr Opin Obstet Gynecol 1994;6: 518.
Koonings PP, Campbell K, Mishell DR Jr, et al. Relative frequency of primary ovarian neoplasms: a 10-year review. Obstet Gynecol 1989;74:921
Kozlowski KJ. Ovarian masses. Adolesc Med 1999;10:337.
Laufer MR, Goldstein DP. Benign and malignant ovarian masses. In: Pediatric and adolescent gynecology, 5th ed. Philadelphia, PA: Lippincott Williams & Wilkins; 2005:685.
Lin P, Falcone T, Tulandi T. Excision of ovarian dermoid cyst by laparoscopy and by laparotomy. Am J Obstet Gynecol 1995; 173:769.
Mane S, Penketh R. Laparoscopic management of benign ovarian disease. Semin Laparosc Surg 1999;6:104.
Muram D, Gale CL, Thompson E. Functional ovarian cysts in patients cured of ovarian neoplasms. Obstet Gynecol 1990; 75:680.
Parker WH, Berek JS. Laparoscopic management of the adnexal mass. Obstet Gynecol Clin North Am 1994;21:79.
Patel MD, Feldstein VA, Lipson SD, et al. Cystic teratomas of the ovary: diagnostic value of sonography. AJR Am J Roentgenol 1998;171:1061.
Porcu E, Venturoli S, Dal Prato L, et al. Frequency and treatment of ovarian cysts in adolescence. Arch Gynecol Obstet 1994;255:69.
Richardson GS, Scully RE, Nikrui N, et al. Common epithelial cancer of the ovary (2). N Engl J Med 1985;312:415.
Spanos WJ. Preoperative hormonal therapy of cystic adnexal masses. Am J Obstet Gynecol 1973;116:551.
Spence JE. Vaginal and uterine anomalies in the pediatric and adolescent patient. J Pediatr Adolesc Gynecol 1998;11:3.
Steinkampf MP, Hammond KR, Blackwell RE. Hormonal treatment of functional ovarian cysts: a randomized, prospective study. Fertil Steril 1990;54:775.
Stepanian M, Cohn DE. Gynecologic malignancies in adolescents. Adolesc Med Clin 2004;15:549.
Templeman C, Fallat ME, Blinchevsky A, et al. Noninflammatory ovarian masses in girls and young women. Obstet Gynecol 2000a;96:229.
Templeman CL, Fallat ME, Lam AM, et al. Managing mature cystic teratomas of the ovary. Obstet Gynecol Surv 2000b;55: 738.
Young JL Jr, Cheng Wu X, Roffers SD, et al. Ovarian cancer in children and young adults in the United States, 1992–1997. Cancer 2003;97:2694
Yuen PM, Yu KM, Yip SK, et al. A randomized prospective study of laparoscopy and laparotomy in the management of benign ovarian masses. Am J Obstet Gynecol 1997;177: 109.