Postmenopausal women at average risk of ovarian cancer may benefit from ROCA (Risk of Ovarian Cancer Algorithm), a new ovarian cancer screening strategy that combines information about trends in CA-125 blood test results and age, followed by transvaginal ultrasound (TVU) as needed and referral to a gynecologic oncologist. Results of a prospective multicenter trial of ROCA were reported at the 44th annual meeting of ASCO (abstract 5003). Results of ROCA testing were used to categorize women as low risk (requiring a repeat CA-125 test in 1 year); intermediate risk (repeat CA-125 test in 3 months); or high risk (TVU and referral to a gynecologic oncologist, who decides, based on clinical findings and the TVU result, whether the patient needs to undergo surgery).
This screening strategy was evaluated in 3,238 postmenopausal women between the ages of 50 and 74 who were followed for up to 8 years. Study participants had no significant history of breast or ovarian cancer. As the investigators expected, each year less than 1% of the women required a TVU. During the study period, 85 women (2.6%) had TVU and a referral to a gynecologic oncologist. Eight women had surgery: three had invasive ovarian cancer, but at an early stage; two had borderline ovarian tumors; and three had benign ovarian tumors. The investigators concluded that “ROCA followed by TVS demonstrated excellent specificity and positive predictive value in a population of US women at average risk for ovarian cancer,” and noted that the findings suggest it is a feasible ovarian cancer screening strategy for women over 50 years of age. A large-scale study of ROCA is underway in the UK, with results expected in 2015.