Cytoreductive surgery and peri-operative intraperitoneal chemotherapy as a curative approach to pseudomyxoma peritonei syndrome

Abstract

Peritoneal carcinomatosis, regardless of primary tumour type, has always been a lethal condition. Recently special treatments using cytoreductive surgery with peritonectomy procedures combined with peri-operative intraperitoneal chemotherapy have resulted in long-term survival. Pseudomyxoma peritonei may be especially appropriate for these aggressive local regional treatments. All patients treated prior to 1999 are presented; patients left with gross residual disease after surgery were not given intraperitoneal chemotherapy, but were later treated with intravenous chemotherapy after cytoreduction. The intraperitoneal chemotherapy was given in the peri-operative period, starting with mitomycin C. For patients whose pathology showed adenomucinosis, intraperitoneal chemotherapy was limited to treatment in the operating theatre with heated mitomycin C. Patients with mucinous adenocarcinoma or pseudomyxoma/adenocarcinoma hybrid had, in addition to mitomycin C, 5 consecutive days of intraperitoneal 5-fluorouracil. A complete cytoreduction was defined as tumour nodules <2.5 mm in diameter remaining after surgery. The histopathology categorized the patients as adenomucinosis, intermediate type, or mucinous carcinomatosis. A prior surgical score was used to estimate the extent of previous surgical procedures. The morbidity of treated patients was 27% and the mortality was 2.7%. In a multivariate analysis, prognostic factors for survival included the completeness of cytoreduction (P<0.0001), the histopathological character of the appendix malignancy (P<0.001) and the extent of previous surgical interventions (P=0.001). Patients with a complete cytoreduction and adenomucinosis by pathology had a 5-year survival of 86%; while hybrid pathology survival at 5 years was 50%. Incomplete cytoreduction had a 5-year survival of 20% and 0% at 10 years. Cytoreductive surgery and peri-operative intraperitoneal chemotherapy is the current standard treatment for selected patients with peritoneal surface spread of appendiceal primary tumours. Similar strategies for other patients with peritoneal surface malignancy such as peritoneal carcinomatosis from colon or gastric cancer, peritoneal sarcomatosis, or peritoneal mesothelioma should be pursued.