Evaluation of short versus long course chemotherapy in the neoadjuvant setting in ovarian cancer

Background: Epithelial ovarian cancer (EOC) is the leading cause of gynecologic cancer deaths and ranks as the seventh most common cancer among women worldwide. The conventional treatment for advanced EOC involves primary debulking surgery (PDS) followed by adjuvant chemotherapy (ACT), but high recurrence rates and chemoresistance hinder this approach. Recent research suggests that neoadjuvant chemotherapy (NACT) followed by interval debulking surgery (IDS) may yield comparable survival rates with fewer postoperative complications, positioning NACT-IDS as a potential alternative for advanced EOC treatment. The optimal number of neoadjuvant chemotherapy cycles for ovarian cancer is still debatable, particularly regarding its effects on survival outcomes. Methods: This is a retrospective cohort study that included newly diagnosed ovarian cancer patients who received NACT and then underwent interval debulking surgery (IDS) at a tertiary cancer center between July 2011 and December 2021. Participants were categorized into two groups according to the number of NACT cycles: Group I (≤4 cycles) and Group II (≥5 cycles). Results: We analyzed 207 patients, Group I included 130 patients (62.8%) while Group II included 77 patients (37.2%). In Group I, 63.1% of patients presented with stage III disease, while stage IV disease was reported in 51.9% of patients. No statistically significant differences were observed between the two groups regarding pathological response to NACT (p = 0.9) or the rate of achieving optimal cytoreduction (p = 0.8). A higher total number of perioperative (pre & post-surgical) chemotherapy cycles was reported in Group II patients (median: 8 vs. 6; p < 0.001). However, overall survival (OS) (p = 0.5) or relapse-free survival (RFS) (p = 0.1) was not different among the two groups. Conclusions: Administering more than four cycles of NACT before cytoreductive surgery did not improve rates of optimal cytoreduction, nor did it affect surgical morbidity, mortality or overall or relapse-free survival.