Is there a CA-125 level that predicts negative second look surgery (SLS) in patients with advanced epithelail ovarian cancer (EOC)?

Abstract

15042 Background: The value of second look surgery (SLS) in advanced epithelial ovarian cancer (EOC) has been has been questioned because performing this procedure has not been associated with a clear survival advantage.However, SLS continues to be the most accurate means of documenting the response to chemotherapy, and therfore still used in investigational protocols. The primary purpose of this study was to assess the levels of CA 125 after treatment, that could predict absence of disease at SLS. Methods: Between 1998 and 2003, 98 stage III EOC patients who underwent optimal cytoreductive surgery, completed 6 cycles of platinum/paclitaxel chemotherapy, and were NED (no evidence of disease: normal CA 125, normal physical and radiological examination) were included in this study. SLS was performed at 6–8 weeks from completion of primary therapy. Patients with disease present at SLS were considered to have persistent disease and received second line chemotherapy. Patient demographics, surgical and chemotherapy treatments, and CA 125 levels prior to start and at completion of primary treatment were collected retrospectively. Survival was estimated by the Kaplan-Meier method. Results: Forty seven out of 98 (48%) of optimally debulked patients who were NED at completion of primary therapy underwent SLS. Twenty-five out of 47 patients (53%) had evidence of disease at SLS and 22 out of 47 patients (47%) were NED at SLS. The median disease free survival was 42 months (95% CI 16, 81) in patients with negative SLS compared with 17 months (95% CI 9, 45) in patients who did not undergo SLS (p = 0.03). Estimated 5-year survival in patients with negative SLS was 90% compared to 50% in patients who did not undergo SLS (p = 0.05). CA 125 levels of ≤ 10 after completion of primary therapy was predictive of negative SLS (p < 0.05). Conclusions: SLS evaluation of disease status appears to be a more accurate than standard clinical evaluation in patients who are NED at completion of their primary therapy. Negative SLS also appears to be a predictor of improved disease free and overall survival. Furthermore, CA 125 ≤ 10 is predictive of negative SLS in patients who are NED after completion of primary therapy. No significant financial relationships to disclose.