Perioperative and Oncological Outcomes of Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy for Peritoneal Metastasis of Rectal Origin.

BACKGROUND: The peritoneum is a common metastatic site of colorectal cancer (CRC) and associated with worse oncological outcomes. Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) has been shown to improve outcomes in selected patients. Studies have demonstrated significant difference in survival of patients with primary colon and rectal tumors both in local and in metastatic setting; but only few assessed outcomes of CRS/HIPEC for rectal and colon tumors. We studied the perioperative and oncological outcomes of patients undergoing CRS/HIPEC for rectal cancer. METHODS: A retrospective analysis of a prospectively maintained database between 2009 and 2021 was performed. RESULTS: 199 patients underwent CRS/HIPEC for CRC. 172 patients had primary colon tumors and 27 had primary rectal tumors. Primary rectal location was associated with longer surgery (mean 4.32, hours vs 5.26 h, p = 0.0013), increased blood loss (mean 441cc vs 602cc, p = 0.021), more blood transfusions (mean 0.77 vs 1.37units, p = 0.026) and longer hospitalizations (mean 10 days vs 13 days, p = 0.02). Median disease-free survival (DFS) was shorter in rectal primary group; 7.03 months vs 10.9 months for colon primaries (p = 0.036). Overall survival was not statistically significant; 53.2 months for rectal and 60.8 months for colon primary tumors. Multivariate analysis indicated origin (colon vs rectum) and Peritoneal Cancer Index to be independently associated with DFS. CONCLUSIONS: Patients with rectal carcinoma undergoing CRS/HIPEC for peritoneal metastasis had worse peri-operative and oncological outcomes. Overall survival was excellent in both groups. This data may be used for risk stratification when considering CRS/HIPEC for patients with rectal primary.

Natural History and Management of Small-Bowel Obstruction in Patients After Cytoreductive Surgery and Intraperitoneal Chemotherapy.

BACKGROUND: Small-bowel obstruction (SBO) after cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) is a common complication associated with re-admission that may alter patients' outcomes. Our aim was to characterize and investigate the impact of bowel obstruction on patients' prognosis. METHODS: This was a retrospective analysis of patients with SBO after CRS/HIPEC (n = 392). We analyzed patients' demographics, operative and perioperative details, SBO re-admission data, and long-term oncological outcomes. RESULTS: Out of 366 patients, 73 (19.9%) were re-admitted with SBO. The cause was adhesive in 42 (57.5%) and malignant (MBO) in 31 (42.5%). The median time to obstruction was 7.7 months (range, 0.5-60.9). Surgical intervention was required in 21/73 (28.7%) patients. Obstruction eventually resolved (spontaneous or by surgical intervention) in 56/73 (76.7%) patients. Univariant analysis identified intraperitoneal chemotherapy agents: mitomycin C (MMC) (HR 3.2, p = 0.003), cisplatin (HR 0.3, p = 0.03), and doxorubicin (HR 0.25, p = 0.018) to be associated with obstruction-free survival (OFS). Postoperative complications such as surgical site infection (SSI), (HR 2.2, p = 0.001) and collection (HR 2.07, p = 0.015) were associated with worse OFS. Multivariate analysis maintained MMC (HR 2.9, p = 0.006), SSI (HR 1.19, p = 0.001), and intra-abdominal collection (HR 2.19, p = 0.009) as independently associated with OFS. While disease-free survival was similar between the groups, overall survival (OS) was better in the non-obstruction group compared with the obstruction group (p = 0.03). CONCLUSIONS: SBO after CRS/HIPEC is common and complex in management. Although conservative management was successful in most patients, surgery was required more frequently in patients with MBO. Patients with SBO demonstrate decreased survival.