Background: Pseudomyxoma peritonei (PMP) is a rare, slowly progressive disease whose prognosis depends primarily on the completeness of cytoreduction. The value of intraoperative hyperthermic intraperitoneal chemotherapy (HIPEC) and of additional factors predicting long-term outcome and disease-free survival (DFS) remains poorly understood. This study aims to analyse survival rates and prognostic factors in patients undergoing maximal cytoreduction and HIPEC.
Methods: Thirty patients were selected from a prospective database of records for patients undergoing cytoreduction and HIPEC with mitomycin C or paclitaxel. Overall survival (OS), DFS, and the prognostic factors influencing them, were examined using multivariate analysis.
Results: Median follow-up was 44 months (range, 8-144). Histological classification of PMPs was DPAM in 6/30 of cases, PMCA-I in 10/30 and PMCA in 14/30. Complete cytoreduction (CC-0 and CC-1) was achieved in 28/30 of patients and CC-2 in 2/30. Median OS was 111 months (range 0-230) and five-year OS rate was 67%. Median DFS was 53.5 months (range 0-120) and 5-year DFS rate was 44%. Incomplete cytoreduction, lymph node involvement and PCI>20 were associated with poor prognosis for OS, while lymph node involvement, elevated CA-125 levels, unfavourable histology and previous chemotherapy were associated with poor outcomes for DFS. There was morbidity of Grade 3 or higher in 9/30. Post-operative mortality occurred in 1 case.
Conclusion: Cytoreduction plus peritonectomy procedures combined with HIPEC is a safe treatment and could improve survival rates. Since the optimal cytoreduction is the primary prognostic factor, patients should be centralised under the care of experienced teams.