Lymphocytic infiltration and Chemotherapy Response Score as prognostic markers in ovarian cancer patients treated with Neoadjuvant chemotherapy.

ABSTRACT

Neoadjuvant Chemotherapy (NACT) followed by Interval Debulking Surgery (IDS) is an accepted frontline treatment in patients with advanced Epithelial Ovarian Cancer (EOC). Histopathologic assessment of tumor post NACT may provide a surrogate for response to treatment. The present study aims to characterize the pathological response and to examine its prognostic significance in these patients. Medical records of women with EOC treated in our institution from 2011 to 2016 were retrospectively identified. IDS specimens were reviewed by study pathologist and Chemotherapy Response Score (CRS), lymphocytic infiltration, necrosis and mitosis were assessed. 55 patients with EOC treated with NACT were identified and 48 had complete clinical and pathological data. Median age was 63 years. CRS assessed at omentum predicted PFS when adjusted for age, stage, debulking status (complete, optimal, suboptimal) and post IDS bevacizumab administration (mPFS CRS 1 vs 2 vs 3 10.3-14-18.7 months 95% CI [7.4-15.7], [12.2-22.9], [13.5-31.3]). Presence of lymphocytic infiltration was associated with improved OS (log-rank test P = 0.015). Post IDS bevacizumab was associated with shorter PFS in patients with lymphocytic infiltration. BRCA status was known for 25 patients and presence of BRCA1/2 mutations was strongly correlated with lymphocytic infiltration (P = 0.011) but not CRS omentum (P = 0.926). Our study confirms the predictive value of CRS in EOC patients treated with NACT and IDS, but also demonstrates the prognostic significance of lymphocytic infiltration as well as its possible interaction with bevacizumab treatment.