Background: We aimed to determine whether the inclusion of additional cycles of carboplatin-paclitaxel is beneficial to patients with high posttreatment serum CA-125 levels. Methods: Among patients who achieved remission after six cycles of carboplatin-paclitaxel chemotherapy, those with CA-125 of 10-35 U/ml at the time of remission were divided into two groups (group A: six cycles of standard chemotherapy vs. group B: two or more additional cycles) and were analyzed. Results: Among the 436 patients with advanced epithelial ovarian cancer, 154 patients (46.8%) had CA-125 of 10-35 U/ml at the time of remission. Fifty-six patients (36.4%) received two or more cycles after the first six cycles of chemotherapy (group B). The addition of two or more cycles of chemotherapy did not improve the progression-free survival (p = 0.660). There was no statistical difference in the rates of CA-125 falling to ! 10 U/ml between the two groups (p = 0.256). Moreover, the degree of CA-125 decrease after six cycles of chemotherapy was similar regardless of the additional cycles (p = 0.656). Conclusion: The addition of two or more cycles of standard chemotherapy based on posttreatment CA-125 levels was not beneficial. Copyright (C) 2011 S. Karger AG, Basel