Aim: Pseudomyxoma peritonei (PMP) is a rare form of peritoneal carcinomatosis characterized by abnormal quantity of extracellular mucinous material. It almost originates from a primary appendiceal tumor with different malignancy degrees. The purpose of this study was to evaluate outcome and long-term survival on 80 patients affected by PMP after cytoreductive surgery (CRS) associated with hyperthermic intraperitoneal chemotherapy (HIPEC).
Methods: From October 1995 to June 2012, about 550 operations for PC were performed; in 300 cases surgical cytoreduction in association with HIPEC was carried out. Regarding PMP, 80 procedures of CRS and HIPEC were performed. This approach is based on surgical removal of the primitive cancer, peritonectomy (stripping of implants on the peritoneal surface) and HIPEC performed with cisplatinum and C mytomicin. The rationale of this treatment is to obtain, after macroscopic disease removal, an elevated and persistent drug concentration in the peritoneal cavity, with limited systemic effects.
Results: The complication rate was 52.5% (42/80) with no postoperative deaths. The median overall and progression-free survival were 144 and 88 months, respectively. Not complete cytoreductive surgery (P<0.001), tumor histology (P=0.02) and previous systemic chemotherapy (p = 0.03) were identified in the univariate analysis as independent predictors for a poorer long-term survival. In the multivariate analysis, the completeness of cytoreduction was the only significant variable influencing the outcome. Incomplete cytoreduction (P<0.01) resulted the only statistically significant variable associated with a higher incidence of postoperative complications.
Conclusion: PMP can be treated with curative intent in a large percentage of cases by cytoreductive surgery associated with HIPEC. This new approach could be performed safely with acceptable morbidity and mortality in selected patients treated in specialized centers. Completeness of cytoreduction allows to achieve the best results.