PM1 - Impact of Socioeconomic Status on Outcomes in Colorectal Cancer with Peritoneal Metastases

Introduction: Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS-HIPEC) can offer significant survival advantage over systemic therapy alone for patients with colorectal peritoneal metastases (CRPM). Low socioeconomic status (SES) has been correlated with disparities in access to CRS-HIPEC. We analyzed the impact of SES on operative management and survival at a tertiary CRS-HIPEC center.

Methods: We conducted a retrospective study examining patients who underwent CRS-HIPEC for CRPM from 2000-2018. Patients were grouped by SES. Baseline characteristics, perioperative outcomes, and survival were examined between groups.

Results: 226 patients were identified: 107 (47%) low and 119 (53%) high SES patients. High SES patients were younger (52 vs 57 years, p=0.005), more likely to be white (95.0% vs 91.6%, p=0.064), employed (65% vs 47%, p<0.05), and privately insured (83% vs 57%, p<0.001). They also had lower burden of comorbidities and frailty (p=0.001). There were no differences in rates of previous resection or chemotherapy, but low SES patients more often had synchronous carcinomatosis at diagnosis (48% vs 35%, p=0.05). Following CRS-HIPEC, low SES patients had higher rates of post-operative complications, readmission, and 90-day mortality (all p<0.05). Median survival following CRS-HIPEC for low SES patients was markedly lower (17.8 vs 32.4 mos, p=0.022) despite comparable PCI, completeness of cytoreduction, and pathologic characteristics. High SES remained a significant predictor of survival on MVA (HR=0.68, p=0.039).

Conclusions: Despite improving therapies for CRPM, low SES patients remain at a significant disadvantage. Even patients who overcome hurdles of access and undergo treatment at a high-volume, tertiary referral center experience worse short- and long-term outcomes. Improving access and addressing these disparities is crucial to ensure equitable outcomes and improve patient care.