BACKGROUND:The aim of this study was to compare debulking surgery and cytoreductive surgery (CRS) in patients with Pseudomyxoma peritonei (PMP) regarding efficacy and safety.PATIENTS AND METHODS:Data were extracted from medical records and treatment outcomes were analyzed for all 152 patients with PMP who were scheduled for debulking surgery and intraperitoneal chemotherapy (IPC) or CRS and IPC at Uppsala University Hospital, Uppsala, Sweden, between September 1993 and December 2008.RESULTS:One hundred and ten patients (73%) were treated with CRS and IPC and 40 (27%) with debulking surgery and IPC. In two patients (1%), surgery was defined as open and close. Patients with CRS and IPC had a 74% 5-year overall survival (OS) rate compared with 40% for those treated with debulking surgery (P < 0.001). Patients with no residual macroscopic tumour (R1 resection) had a better 5-year OS rate of 94% compared with 28% for patients with macroscopic residual tumour (R2) (P < 0.001). Grades II-IV adverse events were seen in 29% of debulked patients and in 47% of CRS/IPC patients (P = 0.053).CONCLUSIONS:CRS and IPC seems more efficient than debulking surgery and IPC but with numerically higher morbidity. Therefore, if surgically possible, CRS should be the treatment of choice for PMP patients. However, debulking surgery may still be of benefit to selected patients for palliative purposes.