312P Elevated serum CA125 predicts recurrence in patients with completely resected ovarian clear cell carcinoma

Abstract

Background The Gynecological Cancer Intergroup has recommended that serum CA125, which is a good predictive marker for recurrence, be included in the criteria for defining response and progression of ovarian carcinoma. However, the criteria were developed on the basis of patients with serous adenocarcinoma. To assess the optimal criteria for patients with clear cell carcinoma, we investigated elevated serum CA125 and recurrence in patients with ovarian clear cell carcinoma. Methods We retrospectively investigated the medical records of patients with ovarian clear cell carcinoma at our hospital between June 1997 and December 2014. Patients with optimally resected and histologically confirmed clear cell carcinoma in our hospital whose serum CA125 level was higher than 35 U/mL before treatment and lower after operation or adjuvant chemotherapy were included in this study. We calculated the sensitivity, specificity, positive and negative predictive values, and time between elevation and radiological recurrence. Results One hundred and thirty nine patients were diagnosed with ovarian clear cell carcinoma during this period. Of these, 55 patients were eligible for the study, and 16 events [A1] [A2] occurred. The sensitivity and specificity of elevated serum CA125 level for predicting recurrence were 68.8% and 97.4%. The positive and negative predictive values were 91.7% and 88.4%. The median time from CA125 elevation to recurrence was 28 days (95% confidence interval: 0-51 days). Conclusions A CA125 level above 35 U/mL was highly specific for predicting recurrence. We should consider radiological examinations for patients with clear cell carcinoma and CA125 levels over 35 U/mL. Legal entity responsible for the study National Cancer Center Hospital Funding N/A Disclosure All authors have declared no conflicts of interest.