Analysis of third-line and fourth-line chemotherapy for recurrent ovarian cancer treated with first-line platinum/taxane regimens

Abstract

15045 Background: Limited information is available regarding to the usefulness of third-line chemotherapy (TLC) and forth-line chemotherapy (FLC) for recurrent ovarian cancer treated with first-line platinum/taxane (PT) regimens. Methods: We retrospectively reviewed the medical records of patients (pts) with ovarian cancer treated with PT regimens at the National Cancer Center Hospital from 1998 to 2004. The aim of this study is to investigate the important clinical factor such as response rate (RR), time to treatment progression (TTP), overall survival (OS) and predictor of response to TLC and FLC. Kaplan-Meier method was used for estimating TTP and OS. Wilcoxon test was performed for survival times and p-values < 0.05 were considered to be statistically significant. Results: There were 183 pts received first-line PT regimens in study period, 77 of 183 pts received second-line chemotherapy (SLC), 61 of 77 progressed after SLC and 55 of 61 pts received TLC. The RR to TLC was 34.5%. The median TTP was 5 months (mo) (range; 1–19 mo) and the median OS was 12 mo (range; 2–38 mo). The TLC regimen was consisted of P and/or T regimens of 36 pts and the other regimens of 19 pts. The RR according to the duration of response of previous chemotherapy (DRPC) (< 6 mo and ≥ 6 mo) were 31.4% and 37.3%, respectively. The median OS of DRPC (< 6 mo and ≥ 6 mo) were 8 mo (range; 2–33 mo) and 12 mo (range; 2–38 mo), respectively (p = 0.002). After TLC 47 pts progressed and 29 pts received FLC. The RR to FLC was 27.5%. The median TTP was 3 mo (range; 0–11 mo). The median OS of 18 pts who didn’t receive FLC and 29 pts received FLC were 2 mo (range; 2–16 mo) and 7 mo (range; 2–25 mo), respectively (p = 0.01). The RR according to DRPC (< 4 mo and ≥ 4mo) were 22.2% and 30%, respectively. The median OS of DRPC (< 4 mo and ≥ 4 mo) were 3 mo (range; 2–23 mo) and 6 mo (range; 2–25 mo), respectively (p = 0.4). Conclusions: The DRPC is considered to be predictor of response to TLC but not to FLC. Giving TLC and FLC if the pts have tolerable may improve OS, however this analysis is prone to several well-established potential biases and limitations. Further prospective study is warranted. [Table: see text]