Exposure to Neoadjuvant Oxaliplatin-Containing Chemotherapy, Does it Effect Intraperitoneal Hyperthermic Chemotherapy Perfusion?

Introduction: Patients undergoing cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) are commonly exposed to oxaliplatin neoadjuvant chemotherapy (NAT) regimens. The impact of systemic exposure to oxaliplatin prior to HIPEC with oxaliplatin is unknown. Methods: We conducted a retrospective review of our institutional registry of CRS/HIPEC cases who received oxaliplatin-containing NAT, and compared patients who underwent HIPEC with oxaliplatin versus cases perfused with mitomycin C. The primary outcome was survival, defined by overall survival (OS) and disease-free survival (DFS). Subgroup analysis was performed based on primary tumor etiology and completeness of cytoreduction. Results: A total of 333 cases satisfied the selection criteria—159 appendiceal primaries (all high-grade disease) and 174 colorectal cases. Thirty-one cases (9.3%) underwent HIPEC with oxaliplatin, with the remaining 302 cases (90.7%) receiving mitomycin C. Both cohorts were identical in regard to baseline characteristics, and both groups were alike in regard to NAT regimens and oxaliplatin exposure. There was no difference in survival outcomes. OS times were 2.9 (± 2.8) and 2.8 (± 3.6) years for oxaliplatin and mitomycin C perfusions, respectively (p = 0.94), and the 5-year OS rates were also similar at 9.7 and 18.5% (odds ratio [OR] 0.49, 95% confidence interval [CI] 0.14–1.67, p = 0.24) for oxaliplatin and mitomycin cases, respectively. Likewise, DFS findings were similar, with survival of 2.5 (± 4.5) and 1.8 (± 2.4) years for oxaliplatin and mitomycin perfusions, respectively (p = 0.21). There was no difference in 5-year DFS rates, at 10.5 and 7.8% (OR 1.39, 95% CI 0.30–6.56, p = 0.68) for oxaliplatin and mitomycin C, respectively. Subgroup analysis found minimal discordant findings from the main results. Conclusion: This analysis found no discernable association with NAT oxaliplatin exposure in regard to survival outcomes following CRS/HIPEC stratified out by perfusion agent.