Radiation Therapy for Recurrent Clear-Cell Cancer of the Ovary

Objective: Given the relative chemo-resistant nature of clear-cell gynecologic cancers, we investigated the utility of radiation therapy (RT) to treat recurrent clear-cell carcinoma (CCC) of the ovary. Methods: A retrospective chart review of patients with recurrent CCC managed from 1994-2012 was conducted at 2 academic medical centers. Demographic and clinicopathologic factors were abstracted and evaluated using Pearson x2 or t tests, Kaplan-Meier and Cox regression analyses. Results: Fifty-three patients had recurrent CCC, and 24 (45.3%) of these patients received RT. There were no significant differences in age, stage, optimal cytoreduction, platinum response, or the percentage of patients that received more than 3 regimens of chemotherapy between the 2 groups. Patients who received RT for recurrent CCC were more likely to have had a focal recurrence (62.5% vs 10.3%, P < 0.001) and to have undergone secondary cytoreduction (70.8% vs 10.3%, P < 0.001). Of patients who received RT, 73.9% underwent surgery with or before their treatment. Five-year survival after recurrence was significantly higher in the group that received RT, 62.9% versus 18.8% (P = 0.002). In a multivariate analysis, platinum-sensitive disease and RT were associated with improved survival from recurrence, (hazard ratio, 0.26; 95% confidence interval, 0.08-0.81; P = 0.02 and hazard ratio, 0.28; 95% confidence interval, 0.09-0.90, P = 0.03, respectively). Conclusions: In this cohort of patients with recurrent CCC, platinum-sensitive disease and RT are associated with improved survival. However, it is important to note that the majority of these patients underwent surgery along with RT, and it may be that the benefit of RT is limited to those who undergo secondary cytoreduction.