Lack of improved survival plus increase in thromboembolic complications in patients with clear cell carcinoma of the ovary treated with platinum versus nonplatinum-based chemotherapy.

BACKGROUND: This study was conducted to evaluate survival rates for patients with clear cell ovarian carcinoma who had platinum-based chemotherapy versus nonplatinum-based chemotherapy and the risk of thromboembolic complications.
METHODS: One hundred and eleven evaluable patients with clear cell ovarian carcinoma who underwent primary surgery and postoperative therapy were retrospectively evaluated. Median follow-up was 21.3 months (range, 3-280 months). Patients treated with platinum-based chemotherapy and nonplatinum-based chemotherapy were evaluated according to stage, age, grade, extent of surgery, and development of thromboembolic complications. Patient populations were compared using the chi-square test. Estimated 5- and 10-year survivals for each group were calculated using the method of Kaplan and Meier. Differences in survival rates were calculated using the log rank test. The frequency of thromboembolic complications in the clear cell ovarian carcinoma group was compared with its frequency in a matched-control group of 109 patients with epithelial nonclear cell ovarian carcinoma.
RESULTS: Seventy-one patients were treated with nonplatinum-based chemotherapy and 40 patients were treated with platinum-based chemotherapy. There was no statistically significant difference in the characteristics of patient populations treated with platinum-based chemotherapy or nonplatinum-based chemotherapy. The estimated 5-year survival for clear cell ovarian carcinoma patients treated with platinum-based chemotherapy did not differ significantly from the estimated 5-year survival for patients with clear cell ovarian carcinoma treated with nonplatinum-based chemotherapy (36% vs. 32%; P = 0.23). Twelve patients with clear cell ovarian carcinoma developed thromboembolic complications remote from primary surgery, whereas in a matched-control group of patients with nonclear cell ovarian carcinoma treated with platinum-based chemotherapy, no patients developed a thromboembolic complications (P = 0.0004). Eight of 40 patients (20%) with clear cell ovarian carcinoma treated with platinum-based chemotherapy developed thromboembolic complications, whereas 4 of 71 patients (6%) treated with nonplatinum-based chemotherapy developed thromboembolic complications (P = 0.03). Multivariate logistic regression analysis demonstrated that the development of a thromboembolic complication was significantly related to clear cell ovarian carcinoma and platinum-based chemotherapy and had a significant (P = 0.009) negative impact on survival.
CONCLUSIONS: Platinum-based chemotherapy did not appear to improve survival compared with nonplatinum-based chemotherapy of patients with clear cell ovarian carcinoma. The combination of platinum-based chemotherapy and clear cell ovarian carcinoma significantly increases the risk for thromboembolic complications and has a significant negative impact on survival.