Essentials of Diagnosis
- Vague gastrointestinal discomfort.
- Pelvic pressure and pain.
- Many cases of early-stage cancer are asymptomatic.
- Pelvic examination, CA 125, and ultrasound are mainstays of diagnosis.
Ovarian tumors are common. Most are benign, but malignant ovarian tumors are the leading cause of death from reproductive tract cancer. The wide range of types and patterns of ovarian tumors is due to the complexity of ovarian embryology and differences in tissues of origin (Table 17-4).
In women with no family history of ovarian cancer, the lifetime risk is 1.6%, whereas a woman with one affected first-degree relative has a 5% lifetime risk. With two or more affected first-degree relatives, the risk is 7%. Approximately 3% of women with two or more affected first-degree relatives will have a hereditary ovarian cancer syndrome with a lifetime risk of 40%. Women with a BRCA1 gene mutation have a 45% lifetime risk of ovarian cancer and those with a BRAC2 mutation a 25% risk. These women should be screened annually with transvaginal sonography (TVS) and CA 125 testing, and prophylactic oophorectomy is recommended by age 35 or whenever childbearing is completed because of the high risk of disease. The benefits of such screening for women with one or no affected first-degree relatives are unproved, and the risks associated with unnecessary surgical procedures may outweigh the benefits in low-risk women.
A. Symptoms and Signs
Unfortunately, most women with both benign and malignant ovarian neoplasms are either asymptomatic or experience only mild nonspecific gastrointestinal symptoms or pelvic pressure. Women with early disease are typically detected on routine pelvic examination. Women with advanced malignant disease may experience abdominal pain and bloating, and a palpable abdominal mass with ascites is often present.
B. Laboratory Findings
An elevated serum CA 125 (> 35 units) indicates a greater likelihood that an ovarian tumor is malignant. CA 125 is elevated in 80% of women with epithelial ovarian cancer overall but in only 50% of women with early disease. Furthermore, serum CA 125 may be elevated in premenopausal women with benign disease such as endometriosis.
C. Imaging Studies
TVS is useful for screening high-risk women but has inadequate sensitivity for screening low-risk women. Ultrasound is helpful in differentiating ovarian masses that are benign and likely to resolve spontaneously from those with malignant potential. Color Doppler imaging may further enhance the specificity of ultrasound diagnosis.
Once an ovarian mass has been detected, it must be categorized as functional, benign neoplastic, or potentially malignant. Predictive factors include age, size of the mass, ultrasound configuration, CA 125 levels, the presence of symptoms, and whether the mass is unilateral or bilateral. In a premenopausal woman, an asymptomatic, mobile, unilateral, simple cystic mass less than 7.5 cm may be observed for 4-6 weeks. Most will resolve spontaneously. If the mass is larger or unchanged on repeat pelvic examination and TVS, surgical evaluation is required.
Most ovarian masses in postmenopausal women require surgical evaluation. However, a postmenopausal woman with an asymptomatic unilateral simple cyst less than 5 cm in diameter and a normal CA 125 level may be followed closely with TVS. All others require surgical evaluation.
Laparoscopy may be used when an ovarian mass is small enough to be removed with a laparoscopic approach. If malignancy is suspected, preoperative workup should include chest x-ray, evaluation of liver and kidney function, and hematologic indices.
If a malignant ovarian mass is suspected, surgical evaluation should be performed by a gynecologic oncologist. For benign neoplasms, tumor removal or unilateral oophorectomy is usually performed. For ovarian cancer in an early stage, the standard therapy is complete surgical staging followed by abdominal hysterectomy and bilateral salpingo-oophorectomy with omentectomy and selective lymphadenectomy. With more advanced disease, aggressive removal of all visible tumor improves survival. Except for women with low-grade ovarian cancer in an early stage, postoperative chemotherapy is indicated. Several chemotherapy regimens are effective, such as the combination of cisplatin or carboplatin with paclitaxel, with clinical response rates of up to 60-70%.
Unfortunately, approximately 75% of women with ovarian cancer are diagnosed with advanced disease after regional or distant metastases have become established. The overall 5-year survival is approximately 17% with distant metastases, 36% with local spread, and 89% with early disease.
Im DD et al: Contemporary management of ovarian cancer. Obstet Gynecol Clin North Am 2001;28;759.
Kauff ND et al: Risk-reducing salpingo-oophorectomy in women with a BRCA1 or BRCA2 mutation. N Engl J Med 2002; 346:1609.
Revision date: June 14, 2011
Last revised: by Janet A. Staessen, MD, PhD