The finding of an adnexal mass is a common clinical scenario in gynecology. Any number of benign causes may be responsible, but it is important to identify which of those masses present a high likelihood of malignancy because complete surgical resection, along with adjuvant therapy administered in a timely manner, will maximize survival.
For that reason, an individualized risk profile in patients who have an adnexal mass confirmed by ultrasonography (US) would assist clinicians in making early referral to a cancer specialty care center.
Researchers evaluated 399 women who had been referred because of an adnexal mass on pelvic examination. Their objective was to estimate the accuracy of the following combination in predicting the risk of malignancy:
- patient demographics
- tumor morphology on US
- the serum CA-125 level.
The serum CA-125 level correlated directly with risk of malignancy in women who had an adnexal mass: Only 7.7% of women whose serum CA-125 level was within the normal range had ovarian cancer, compared with 34.2% women whose CA-125 level was 35–59 U/mL, and 86.8% whose level was 60–120 U/mL (P < .001). Multivariate analysis revealed that the most accurate significant predictor of a high risk of malignancy in patients who have an adnexal mass with complex or solid morphology is a serum CA-125 level >35 U/mL. This cutoff yielded a sensitivity of 77.3% for early stage ovarian cancer and 98.6% for advanced stage disease.
In summary
To repeat: As we await results of the UKCTOCS and the PLCO trial, do not screen patients routinely for ovarian cancer. Women who have an adnexal mass, an elevated CA-125 level, and troubling US findings should be referred—early—to a specialist.
WHAT THIS EVIDENCE MEANS FOR PRACTICE
Refer women who have a complex or solid adnexal mass and a CA-125 level >35 U/mL to a specialist. Early referral is important: Studies have shown a survival advantage as high as 24% among patients who have early-stage ovarian cancer and are treated by a gynecologic oncologist.6,7
The only benign histologic finding consistently associated with an elevated serum CA-125 level is ovarian endometriosis. In patients who have a history of endometriosis or other symptoms consistent with endometriosis, and an elevated CA-125 level, ovarian cancer is much less likely.
Also be aware that all 54 patients in this study who had ascites on US had invasive epithelial ovarian cancer, giving that finding a positive predictive value of 100%.