Advancing Treatment Outcomes for Peritoneal Surface Malignancies in Low- and Middle-Income Countries: Insights from the First Multicenter Study in North Africa.

Background: Peritoneal surface malignancies (PSM) are aggressive cancers with limited treatment access in low- and middle-income countries (LMICs). While cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) have improved survival outcomes globally, their feasibility in LMICs remains underexplored. This first multicenter study in North Africa evaluates the implementation and outcomes of CRS with or without HIPEC in resource-limited settings. Methods: A retrospective cohort study of 391 patients with PSM (colorectal cancer, pseudomyxoma peritonei, ovarian cancer, gastric cancer, or mesothelioma) treated with CRS ± HIPEC between 2014 and 2020 at four tertiary centers in Morocco, Tunisia, and Algeria. Primary outcomes included overall survival (OS), disease-free survival (DFS), and severe postoperative morbidity (Clavien-Dindo ≥ IIIa). Cox regression was used to identify independent prognostic factors. Results: Among 391 patients, complete cytoreduction (CC-0/1) was achieved in 88%, and HIPEC was performed in 39%. Severe morbidity occurred in 22%, with HIPEC, spleno-pancreatectomy, and incomplete cytoreduction (CC-2) identified as significant risk factors. The median OS was 68 months, with 1- and 5-year survival rates of 97% and 56%, respectively. Patients undergoing CRS + HIPEC had significantly longer OS than CRS alone (70 vs. 64 months, p = 0.016), though DFS was not significantly different between groups. Independent predictors of improved OS included HIPEC, CC score, PCI, and primary tumor type. Conclusions: This first North African multicenter study establishes the feasibility and efficacy of CRS and HIPEC in LMICs, achieving survival outcomes comparable to high-income settings. The findings support expanding advanced PSM treatment programs in resource-limited settings, emphasizing structured training and multidisciplinary collaboration to improve access and outcomes.