CA-125 and other prognostic factors associated with survival in stage I epithelial ovarian cancer: a study of 15,882 patients

Abstract

<h3>Objectives:</h3> To investigate the prognostic value of demographic and clinicopathologic factors including CA-125 levels in patients with stage I epithelial ovarian carcinoma. <h3>Methods:</h3> Data was obtained from the National Cancer Database (NCDB PUF 2016). Patients were diagnosed with stage I epithelial ovarian cancer between 2004 and 2015. CA-125 results were reported as abnormal if they were ≥35 units/mL before treatment. Kaplan-Meier method, log-rank test, and multivariate Cox proportional hazards modeling were used for statistical analyses. <h3>Results:</h3> Of 15,882 patients with stage I epithelial ovarian carcinoma, the median age was 55 (range 18-90). The majority of patients were White (80.4%) and the remainder were Hispanic (6.4%), Black (6.1%), and Asian (5%). Stage IA, IB, IC, and stage I NOS were found in 54.2%, 3.8%, 36.3%, 5.7% of patients, respectively. There were 25.2% with endometrioid carcinoma, 20.9% with serous carcinoma, 20.7% with mucinous carcinoma, 15.6% with clear cell carcinoma and 17.6% with other epithelial subtypes. The 5-year overall survival (OS) was 86.0%. Black race was associated with worse OS at 82.6% compared to 85.6% of Whites (P=0.024). Those with higher substage IC vs IA and IB had worse survivals (82.7% vs 88.4% and 85.3%; P<0.001 and P=0.042). Those with clear cell or serous carcinoma had poorer outcomes compared to those with mucinous (83.0% or 84.4% vs 87.2%; P<0.001 or P=0.016) and endometrioid carcinoma (90.9%; P<0.001 or P<0.001). Tumors with LVSI had associated survival of 75.2% compared to 87.5% in those without LVSI (P<0.001). Patients with elevated pretreatment CA-125 levels had 84.4% OS compared to 89.4% for those with normal CA-125 values (P<0.001). Multivariate analysis demonstrated that Black vs. White race (HR=1.32, 95% CI, 1.10-1.59; P<0.003), Southern vs Northeast Region (HR=1.23, 95% CI, 1.07-1.40; P<0.003), mucinous vs serous histology (HR=1.67, 95% CI, 1.41-1.98; P<0.001), clear cell vs serous histology (HR=1.26, 95% CI, 1.08-1.46; P<0.003), stage IC vs IA (HR=1.50, 95% CI, 1.35-1.67; P<0.001), LVSI (HR=1.82, 95% CI, 1.35-2.45; P<0.001), grade 3 vs 1 (HR=2.21 95% CI, 1.87-2.61, P<0.001) and elevated vs normal CA-125 (HR=1.50, 95% CI, 1.31-1.71, P<0.001) were independent predictors for worse survival. <h3>Conclusions:</h3> Our data suggest that pretreatment CA-125 is an independent prognostic factor in women with stage I epithelial ovarian cancer. Other predictors of survival include race, region, sub-stage, cell type, grade, and LVSI.