Histopathology predicts clinical outcome in advanced epithelial ovarian cancer patients treated with neoadjuvant chemotherapy and debulking surgery

Objective To analyze the factors prognostic of survival in patients with advanced epithelial ovarian cancer (EOC) treated with neoadjuvant chemotherapy (NAC) followed by interval debulking surgery. Methods Outcomes were retrospectively in patients with advanced EOC or peritoneal cancer who received neoadjuvant paclitaxel and carboplatin chemotherapy every 3 weeks for three to four cycles, followed by interval debulking surgery and three additional cycles of the same regimens from January 2001 to November 2010. Therapeutic response was assessed histopathologically as grade 0 to 3, based on the degree of disappearance of cancer cells, displacement by necrotic and fibrotic tissue, and tumor-induced inflammation. Factors prognostic of progression-free survival (PFS) and overall survival (OS) were calculated. Results The 124 enrolled patients had a median age of 62 years (range, 35-79 years). Viable cancer cells were observed in specimens resected from 72 patients (58%) at interval debulking surgery after NAC. Multivariate analysis using the Cox proportional hazard model showed that advanced (stage IV) disease (hazard ratio [HR] = 1.94, p = 0.003), residual cancer at the end of surgery ≥ 1 cm (HR = 3.78, p < 0.001), and histological grade 0-1 (HR = 1.65, p = 0.03) were independent predictors of decreased OS. Grade 0-1 was also an independent predictor of increased risk of relapse within 6 months (odds ratio = 8.42, p = 0.003). Conclusions Residual disease of ≥ 1 cm, advanced stage, and the presence of more viable disease in resected specimens are prognostic factors for survival in advanced EOC patients receiving NAC followed by interval debulking surgery.