Adjuvant chemotherapy for stage I ovarian clear cell carcinoma: Patterns of use and outcomes.

OBJECTIVE

The aim of this study was to investigate the patterns of use and outcomes of adjuvant chemotherapy for patients diagnosed with FIGO stage I ovarian clear cell carcinoma (OCCC).

METHODS

A cohort of patients diagnosed between 2004 and 2015 with OCCC was drawn from the National Cancer Database. Those with stage I disease who had primary surgery and underwent systematic lymphadenectomy (defined as at least 10 lymph nodes removed) were selected for further analysis. Factors associated with the administration of adjuvant chemotherapy were investigated with multivariate logistic regression. Overall survival (OS) was evaluated using Kaplan-Meier curves for patients diagnosed between 2004 and 2014, while comparisons were made with the log-rank test. Multivariate Cox analysis was performed to control for possible confounders.

RESULTS

A total of 2325 patients met the inclusion criteria. Median age was 55 years. The majority were White (86.6%). Adjuvant chemotherapy was administered to 1839 (79.1%) patients. Hospital type and location, patient age, disease sub-stage, and year of diagnosis were independently associated with the administration of chemotherapy. Patients who received adjuvant chemotherapy (n = 1629) had better OS than those who did not (n = 443), (5-year OS rates 89.2% vs 82.6%, p < 0.001). After controlling for disease sub-stage, age, race, hospital type and medical comorbidities, adjuvant chemotherapy was associated with better overall survival (HR: 0.59, 95% CI: 0.45, 0.78).

CONCLUSIONS

Adjuvant chemotherapy could be associated with a survival benefit for patients with stage I OCCC.