Purpose The three principal studies dedicated to the natural history of peritoneal carcinomatosis (PC) from colorectal cancer consistently showed median survival ranging between 6 and 8 months. New approaches combining cytoreductive surgery and perioperative intraperitoneal chemotherapy suggest improved survival. Patients and Methods A retrospective multicenter study was performed to evaluate the international experience with this combined treatment and to identify the principal prognostic indicators. All patients had cytoreductive surgery and perioperative intraperitoneal chemotherapy (intraperitoneal chemohyperthermia and/or immediate postoperative intraperitoneal chemotherapy). PC from appendiceal origin was excluded. Results The study included 506 patients from 28 institutions operated between May 1987 and December 2002. Their median age was 51 years. The median follow-up was 53 months. The morbidity and mortality rates were 22.9% and 4%, respectively. The overall median survival was 19.2 months. Patients in whom cytoreductive surgery was complete had a median survival of 32.4 months, compared with 8.4 months for patients in whom complete cytoreductive surgery was not possible (P < .001). Positive independent prognostic indicators by multivariate analysis were complete cytoreduction, treatment by a second procedure, limited extent of PC, age less than 65 years, and use of adjuvant chemotherapy. The use of neoadjuvant chemotherapy, lymph node involvement, presence of liver metastasis, and poor histologic differentiation were negative independent prognostic indicators. Conclusion The therapeutic approach combining cytoreductive surgery with perioperative intraperitoneal chemotherapy achieved long-term survival in a selected group of patients with PC from colorectal origin with acceptable morbidity and mortality. The complete cytoreductive surgery was the most important prognostic indicator.

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: 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.