Extremely high peritoneal cancer index in colorectal peritoneal metastases demonstrates safety and overall survival benefit in selected patients undergoing cytoreductive surgery and heated intraperitoneal chemotherapy.

BACKGROUND: Colorectal peritoneal metastases are a devastating consequence of colorectal cancer (CRC) with extremely poor prognosis. Patients that can undergo complete cytoreduction by cytoreductive surgery and heated intraperitoneal chemotherapy (CRS/HIPEC) have a markedly improved overall survival. Traditionally, patients with extremely high peritoneal cancer index (PCI), PCI >20, are not offered CRS/HIPEC. METHODS: We performed a retrospective analysis of our prospectively maintained CRS/HIPEC database and evaluated all patients with CRC peritoneal metastases between 2012 and 2022. We divided the cohorts between those with low operative PCI (PCI<20) and high operative PCI (PCI =>20). We examined demographic, clinicopathologic data, perioperative, and oncological outcomes between the cohorts. RESULTS: Of the 691 patients who underwent CRS/HIPEC, 289 were evaluable with CRC metastases, 234 with PCI <20 and 43 with PCI => 20. Median radiologic preoperative and operative PCI was 4 and 10 versus 7 and 24.5 in the low and high PCI cohorts, respectively. Operative time was longer (6 vs. 4 h) and blood loss higher (500 vs. 400 mL) in the high PCI cohort. All other demographic, clinicopathological, and operative characteristics were similar. Median disease free survival (DFS) was longer in the low PCI cohort (11.5 vs. 7 months) but overall survival (OS) showed benefit (41.3 vs. 31.8 months), (p = 0.001 and p = 0.189, respectively), comparatively with an only chemotherapy strategy. CONCLUSIONS: Appropriately selected patients with CRC metastases and extremely high PCI demonstrate similar perioperative safety outcomes in experienced tertiary referral centers. Despite a shorter median DFS, these carefully selected patients demonstrated similar median OS.

Inflammatory Bowel Disease in Cytoreductive Surgery and Heated Intraperitoneal Chemotherapy.

BACKGROUND: Inflammatory bowel diseases (IBDs) pose an increased risk of gastrointestinal cancer with especially worse prognosis. Cytoreductive surgery and heated intraperitoneal chemotherapy (CRS/HIPEC) improves outcomes in selected patients with colorectal peritoneal metastases. Little published data describes the outcomes of CRS/HIPEC in IBD patients. METHODS: We performed a retrospective review of a prospectively maintained CRS/HIPEC database. Outcomes in patients with and without IBD were compared for short-term outcomes such as hospital/intensive care unit stay, blood loss/transfusions, complications, and reoperations. We also examined oncological outcomes including recurrence, overall (OS), and disease-free survival (DFS). RESULTS: We identified 232 patients that underwent CRS/HIPEC for colorectal or small bowel adenocarcinoma, of which 10 were with IBD. Patients with IBD had lower ASA (p=0.005), less hypertension (p=0.033), and 30% small bowel primary compared to none in the non-IBD cohort (p<0.001). Otherwise, demographic and perioperative characteristics were similar between the groups. The median peritoneal cancer index (PCI) was 7 and similar between the cohorts (p=0.422). Extent of organ resections and peritonectomies performed were similar. Complications occurred in 60.3% of patients (21.2% major), similar between the groups (p=0.744 and p=0.444, respectively). Reoperation rate of 27% was similar between groups (p=0.097). The median OS in the IBD cohort was 19.6 vs 53.2 months in the non-IBD cohort (p = 0.056). The median DFS in the IBD cohort was 4.9 vs 9.4 months in the non-IBD cohort (p=0.174). DISCUSSION: Cytoreductive surgery and heated intraperitoneal chemotherapy in patients with IBD has similar complication profile and trended towards poorer oncological outcomes as CRS/HIPEC in non-IBD patients.