Purpose: Pseudomyxoma peritonei (PMP) originating from an appendiceal mucinous neoplasm remains a biologically heterogeneous disease. The purpose of our study was to evaluate outcome and long-term survival after cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) consolidated through an international registry study. Patients and Methods: A retrospective multi-institutional registry was established through collaborative efforts of participating units affiliated with the Peritoneal Surface Oncology Group International. Results: Two thousand two hundred ninety-eight patients from 16 specialized units underwent CRS for PMP. Treatment-related mortality was 2% and major operative complications occurred in 24% of patients. The median survival rate was 196 months (16.3 years) and the median progression-free survival rate was 98 months (8.2 years), with 10- and 15-year survival rates of 63% and 59%, respectively. Multivariate analysis identified prior chemotherapy treatment (P < .001), peritoneal mucinous carcinomatosis (PMCA) histopathologic subtype (P < .001), major postoperative complications (P = .008), high peritoneal cancer index (P = .013), debulking surgery (completeness of cytoreduction [CCR], 2 or 3; P < .001), and not using HIPEC (P = .030) as independent predictors for a poorer progression-free survival. Older age (P = .006), major postoperative complications (P < .001), debulking surgery (CCR 2 or 3; P < .001), prior chemotherapy treatment (P = .001), and PMCA histopathologic subtype (P < .001) were independent predictors of a poorer overall survival. Conclusion: The combined modality strategy for PMP may be performed safely with acceptable morbidity and mortality in a specialized unit setting with 63% of patients surviving beyond 10 years. Minimizing nondefinitive operative and systemic chemotherapy treatments before definitive cytoreduction may facilitate the feasibility and improve the outcome of this therapy to achieve long-term survival. Optimal cytoreduction achieves the best outcomes.

Purpose: Peritoneal carcinomatosis (PC) from colorectal cancer traditionally is considered a terminal condition. Approaches that combine cytoreductive surgery (CRS) and perioperative intraperitoneal chemotherapy (PIC) have been developed recently. The purpose of this study was to assess early and long-term survival in patients treated with that strategy. Patients and Methods: A retrospective-cohort, multicentric study from French-speaking countries was performed. All consecutive patients with PC from colorectal cancer who were treated with CRS and PIC (with or without hyperthermia) were included. Patients with PC of appendiceal origin were excluded. Results: The study included 523 patients from 23 centers in four French-speaking countries who underwent operation between 1990 and 2007. The median follow-up was 45 months. Mortality and grades 3 to 4 morbidity at 30 days were 3% and 31%, respectively. Overall median survival was 30.1 months. Five-year overall survival was 27%, and five-year disease-free survival was 10%. Complete CRS was performed in 84% of the patients, and median survival was 33 months. Positive independent prognostic factors identified in the multivariate analysis were complete CRS, PC that was limited in extent, no invaded lymph nodes, and the use of adjuvant chemotherapy. Neither the grade of disease nor the presence of liver metastases had a significant prognostic impact. Conclusion: This combined treatment approach against PC achieved low postoperative morbidity and mortality, and it provided good long-term survival in patients with peritoneal scores lower than 20. These results should improve in the future, because the different teams involved will gain experience. This approach, when feasible, is now considered the gold standard in the French guidelines.

Purpose: This multi-institutional registry study evaluated cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC) for diffuse malignant peritoneal mesothelioma (DMPM).Patients and Methods: A multi-institutional data registry that included 405 patients with DMPM treated by a uniform approach that used CRS and HIPEC was established. The primary end point was overall survival. The secondary end point was evaluation of prognostic variables for overall survival.Results: Follow-up was complete in 401 patients (99%). The median follow-up period for the patients who were alive was 33 months (range, 1 to 235 months). The mean age was 50 years (standard deviation [SD], 14 years). Three hundred eighteen patients (79%) had epithelial tumors. Twenty-five patients (6%) had positive lymph nodes. The mean peritoneal cancer index was 20. One hundred eighty-seven patients (46%) had complete or near-complete cytoreduction. Three hundred seventy-two patients (92%) received HIPEC. One hundred twenty-seven patients (31%) had grades 3 to 4 complications. Nine patients (2%) died perioperatively. The mean length of hospital stay was 22 days (SD, 15 days). The overall median survival was 53 months (1 to 235 months), and 3- and 5-year survival rates were 60% and 47%, respectively. Four prognostic factors were independently associated with improved survival in the multivariate analysis: epithelial subtype (P < .001), absence of lymph node metastasis (P < .001), completeness of cytoreduction scores of CC-0 or CC-1 (P < .001), and HIPEC (P = .002).Conclusion: The data suggest that CRS combined with HIPEC achieved prolonged survival in selected patients with DMPM.