Treatment outcome of stage Ic ovarian clear cell carcinoma compared to non-clear cell type

Abstract

Objective : The aim was to evaluate the treatment outcome of stage Ic clear cell carcinoma of the ovary compared to that of non-clear cell carcinoma of the same stage.

Methods : Having searched the tumor registry database of the Department of Obstetrics and Gynecology, King Chulalongkorn Memorial Hospital from June 1997- December 2002, we enrolled all patients with stage Ic (according to FIGO staging criteria) clear cell carcinoma who underwent complete surgical staging procedure. Patients with non-clear cell adenocarcinoma of the ovary were enrolled by the same criteria as control group. They all received postoperative adjuvant chemotherapy with single-agent platinum based regimen. The clinical characteristics, survival time, and recurrence free survival of both groups were compared.

Result : A total of 56 patients with stage Ic carcinoma of the ovary were recruited into this study. The mean age was 50 years (36 - 86 years old) in both groups. The median follow-up duration in the clear cell and non-clear cell groups were 61 months (5 - 120 months) and 67 months (15 -103 months), respectively. The mean tumor diameter in the clear cell group was significantly larger than that of the control group (12.96 vs. 9.89 cm; P-value = 0.001). Other clinical characteristics of the two groups were similar. The recurrence rate of the clear cell and non-clear cell groups were 46.4% vs. 14.2% (P = 0.004) and the median time to recurrence were 10.5 months (2 – 35 months) vs. 8 months (3 - 28 months), respectively. The estimated 5-year survival for the clear cell group was significantly lower than that of the non-clear cell (53.6% vs. 85.7%; P-value = 0.01).

Conclusion : Clear cell carcinoma of the ovary stage Ic have lower 5-year survival rate and recurrence free survival than that of the patients with non-clear cell epithelial ovarian carcinoma in the same stage. Combined chemotherapy may be needed to improve the survival of patients in stage Ic clear cell ovarian cancer.