Prognostic Importance of Preoperative CA-125 in International Federation of Gynecology and Obstetrics Stage I Epithelial Ovarian Cancer: An Australian Multicenter Study

Abstract

Purpose To evaluate the prognostic significance of preoperative CA-125 levels on overall survival of patients with International Federation of Gynecology and Obstetrics (FIGO) stage I epithelial ovarian cancer (EOC). Patients and Methods Data from 518 patients with FIGO stage I EOC treated in seven gynecologic oncology centers throughout Australia between 1990 and 2002 were analyzed. Patients with borderline tumors and nonepithelial ovarian carcinomas were excluded, as were women in whom CA-125 had not been determined preoperatively. Preoperative CA-125 levels were studied in surgically staged and incompletely staged patients and compared with prognostic factors, such as substage, grade, and histologic type. Multivariate Cox models were calculated. Results CA-125 levels more than 30 U/mL were associated with higher grade, substage 1B and 1C, nonmucinous histologic type, and older age. In univariate analysis, higher histologic grade, the absence of surgical staging, and preoperative CA-125 levels more than 30 U/mL were associated with impaired survival. Multivariate analysis identified histologic grade, preoperative CA-125, and surgical staging as independent predictors for survival. In the subgroup of completely surgically staged patients, the 5-year overall survival rate was 82% (95% CI, 76% to 88%) for patients with CA-125 levels more than 30 U/mL and 95% (95% CI, 90% to 99%) for patients with CA-125 levels of 30 U/mL or less (P = .028). In the group of incompletely staged patients, the 5-year survival rates were similar for patients with elevated and normal serum CA-125 levels. Conclusion Complete surgical staging, histologic grade, and preoperative serum CA-125 levels are independent prognostic factors and should be included in the decision making for chemotherapy.