A new prognostic model for FIGO stage 1 epithelial ovarian cancer

Abstract Background. No consensus exists which patients with surgical stage 1 epithelial ovarian should receive postoperative chemotherapy. The purpose of this study was to evaluate the prognostic impact of preoperative CA-125 and to establish a prognostic index to identify patients in different risk categories. Methods. Data of 600 surgically staged patients with FIGO stage 1 EOC treated in eleven gynecological cancer centers in Australia, the USA and Europe were analyzed. Eligible patients include those with invasive EOC where a preoperative CA-125 was obtained and standard surgical staging performed. Overall survival (OS) was chosen as study endpoint. Preoperative CA-125 values were compared with other prognostic factors, and univariate and multivariate Cox models were calculated. Results. Two hundred and one patients (33.5%) had preoperative CA-125 ≤30 U/ml and CA-125 levels ≤30 U/ml were associated with lower grade, substage 1A and mucinous histologic cell type. Patients with elevated CA-125 levels were more likely to receive chemotherapy. OS probability was 95% and 85% for patients with pretreatment CA-125 ≤30 U/ml and >30 U/ml, respectively ( p 0.003). Multivariate analysis confirmed preoperative serum CA-125 >30 U/ml (OR 2.7) and age at diagnosis >70 years (OR 2.6) as the only independent predictors for overall survival. Conclusion. Pretreatment of CA-125 ≤30 U/ml dominates over histologic cell type, substage and grade to identify a subgroup of FIGO stage 1 patients with a genuinely good prognosis with extremely good survival and who could possibly be spared with adjuvant chemotherapy.