The prognostic value of perioperative, pre-systemic therapy CA125 levels in patients with high-grade serous ovarian cancer.

OBJECTIVE: To investigate the ability of preoperative CA125 and post-surgical CA125 changes to predict outcomes among patients with high-grade serous ovarian cancer (HGSC).

METHODS: The present retrospective cohort study included patients with HGSC who underwent surgery between January 1, 2003, and December 31, 2011 at Princess Margaret Cancer Center, Toronto, ON, Canada. CA125 was measured at diagnosis and following surgery, and the CA125 ratio was calculated (preoperative CA125/postoperative CA125). Optimal CA125 cutoff levels were identified using the point with the most significant log-rank-test result. Univariate and multivariate analyses with Cox proportional hazard modeling was used to study overall survival.

RESULTS: Among 212 patients, an optimal baseline CA125 cutoff value of 174 U/mL and a seven-fold decrease in CA125 after surgery were positive prognostic indicators. A 10-fold increase in baseline CA125 was associated with decreased overall survival (univariate hazard ratio 1.55, 95% confidence interval [CI] 1.17-2.06; P=0.002; multivariate hazard ratio 1.72, 95% CI 1.21-2.44; P=0.002). An increase in the CA125 ratio (log10 [preoperative CA125/postoperative CA125]) was associated with improved overall survival (univariate hazard ratio 0.63, 95% CI 0.43-0.90; P=0.012; multivariate hazard ratio 0.41, 95% CI 0.24-0.70, P<0.001).

CONCLUSION: CA125 demonstrated prognostic value for HGSC; baseline CA125 of 174 U/mL or lower and a post-surgical decline of seven-fold or greater were associated with improved overall survival.