Clinical characteristics and prognostic factors of stage IC ovarian clear cell carcinoma: a Surveillance, Epidemiology, and End Results (SEER) analysis

Abstract

Purpose The study aimed to investigate the clinical characteristics and prognostic factors of stage IC ovarian clear cell carcinoma (OCCC). Methods The Surveillance, Epidemiology, and End Results (SEER) database was accessed for medical records of patients with stage IC OCCC from 1992 to 2016. The clinical and prognostic features of stage IC OCCC from several therapeutic perspectives were identified with Kaplan–Meier method and Cox proportional hazards model. Results Totally, 1079 patients were enrolled for the analysis. The median age was 55 (range 24–91) years. 850 (78.8%) patients were treated with chemotherapy, 877 (81.3%) received lymph node (LN) dissection, and 20 (1.9%) underwent radiotherapy. LN dissection (P = 0.501) and chemotherapy (P = 0.130) did not significantly impact cancer-specific survival (CSS). Among patients younger than 45 years, 23 received fertility-sparing surgery (FSS). No significant difference in CSS was observed between the FSS and non-FSS group (P = 0.523). Bilateral tumor (P < 0.001) and larger tumor size (P = 0.010) were significantly and independently associated with poor CSS. Older age (P = 0.001), bilateral tumor (P < 0.001), and larger tumor size (P = 0.005) were significantly and independently associated with poor overall survival (OS), while LN dissection (P = 0.005) was significantly and independently associated with better OS. Significant differences in CSS (P = 0.005) and OS (P < 0.001) were observed between the low- and high-risk groups, which were divided by median risk score. Conclusion LN dissection and chemotherapy did not significantly impact CSS, while LN dissection was an independent prognostic factor for OS. Convincing evidence from clinical trials with a large number of patients are further required to develop treatment guidelines.