Adjuvant Therapy in Early Uterine Serous Carcinoma.

Objective: Uterine serous carcinoma (USC) is a rare diagnosis but associated with high mortality. There is limited data to guide adjuvant treatment decisions in early stage disease. The purpose of this study is to evaluate the impact of adjuvant therapy on recurrence-free survival (RFS) and overall survival (OS) in early stage USC.

Methods: Patients with stage I and II USC treated at a single institution from 1/2006-12/2019 were identified. Demographic, clinicopathologic, treatment and outcome data were collected. Data were compared using descriptive statistics. Survival analyses were performed using Kaplan-Meier and Cox proportional hazard methods.

Results: Ninety-four patients were identified. Median follow-up time was 33.5 months. The median age was 68 years (range 49-87), the majority of patients were white (n=78, 83.0%), and the median BMI was 30.7 (range 14.2-57.3). Minimally-invasive surgical staging was performed in 59.6% of cases (n=56). Most patients had stage IA disease (n=70, 74.5%). Most patients (n=79, 84.0%) received adjuvant therapy, and a majority of patients received a combination of systemic chemotherapy and radiation therapy (n=55, 58.5%), with the most common combination being chemotherapy plus vaginal brachytherapy (n=42, 44.7%). Most patients (n=77, 81.9%) remain without evidence of disease, while 17 patients (18.1%) have recurred. Patients receiving 6 cycles of adjuvant chemotherapy experienced improved OS (p=0.004) and improved RFS (p=0.02) compared to those receiving no adjuvant chemotherapy.

Conclusion: Patients with early stage USC who received six cycles of adjuvant chemotherapy had significantly improved OS and RFS when compared to those patients who did not receive adjuvant chemotherapy.