Abstract
OBJECTIVE: We sought to describe clinicopathologic and treatment factors associated with oncologic outcomes in patients with early-stage ovarian clear cell carcinoma undergoing complete staging and in a sub-set of these patients undergoing fertility-conserving surgery. METHODS: We retrospectively identified patients with ovarian clear cell carcinoma initially treated at our institution from January 1, 1996 to March 31, 2020. Survival was estimated using Kaplan-Meier curves and compared by log-rank test. Survival-associated variables were identified by Cox proportional hazards regression. RESULTS: Of 182 patients, mismatch repair and p53 protein expression were assessed by immunohistochemistry on 82 and 66 samples, respectively. There were no significant differences in progression-free survival or overall survival between mismatch repair-deficient (n=6, including 4 patients with Lynch syndrome; 7.3%) and mismatch repair-proficient patients, whereas aberrant p53 expression (n=3; 4.5%) was associated with worse progression-free (p<0.001) and overall survival (p=0.01). Patients with stage IA/IC1 disease had a 95% 5-year overall survival rate (95% CI 88% to 98%); patients with stage IC2/IC3 disease had a similar 5-year overall survival rate (76%; 95% CI 54% to 88%) to that of patients with stage IIA/IIB disease (82%; 95% CI 54% to 94%). There was no difference in 5-year overall survival in patients with stage IA/IC1 undergoing chemotherapy versus observation (94% vs 100%). Nine patients underwent fertility-sparing surgery and none experienced recurrence. Of five patients who pursued fertility, all had successful pregnancies. CONCLUSIONS: In patients with completely staged ovarian clear cell carcinoma, those with stage IA/IC1 disease have an excellent prognosis, regardless of chemotherapy. Aberrant p53 expression may portend worse outcomes. Additional investigation is warranted on the safety of fertility conservation in patients with stage IA/IC1 disease.