Improved survival of patients with pseudomyxoma peritonei receiving intraperitoneal chemotherapy with cytoreductive surgery: a systematic review and meta-analysis.

BACKGROUND Pseudomyxoma peritonei (PMP) is an uncommon but lethal variant of adenocarcinoma. Many recent case series have reported improved survival with the combination of cytoreductive surgery and intraperitoneal chemotherapy (IPEC) in treating PMP. The aim of this study was to analyze the published studies for improved survival with this treatment strategy. METHODS Data from all studies using IPEC in treating PMP were analyzed. We searched PubMed, MEDLINE, and the Cochrane Library (through September 2011). Studies were limited to English and PMP with appendiceal origin. Twenty-nine studies were identified, with 15 studies from different treatment centers that were specifically analyzed for differences in 5-y mortality and morbidity. Observed to expected (OE) ratios were calculated for both mortality and morbidity. RESULTS Mean and median 3-y, 5-y, and 10-y survival rates were 77.18%/77.85%, 76.63%/79.5%, and 57.3%/55.9%, respectively. Of the 10 studies that had sufficient data to calculate OE ratios from the 5-year mortality data, two had OE ratios lower than 1. Of the 11 studies that had data sufficient to calculate OE ratios from the morbidity data, four had OE ratios that were less than 1. CONCLUSIONS Combining cytoreductive surgery and IPEC improves the survival of patients with PMP, regardless of treatment modality. Although this treatment strategy is associated with an increased risk of morbidity, the increase in survival may be acceptable in proposing an alternative to debulking procedures alone.