# Cytoreductive surgery and HIPEC for multicystic peritoneal mesothelioma: therapeutic approach in a rare benign neoplasm

## TL;DR

A 32-year-old woman with a rare benign tumor was successfully treated with surgery and heated chemotherapy, showing no recurrence after six months.

## Contribution

This case highlights the effectiveness of combining cytoreductive surgery with HIPEC for managing multicystic peritoneal mesothelioma.

## Key findings

- Complete cytoreductive surgery and HIPEC led to successful removal of the tumor with no recurrence at 6 months.
- Histopathology confirmed the tumor was benign with a mesothelial immunophenotype.
- The treatment approach suggests lasting disease control is possible for this rare condition.

## Abstract

Multicystic peritoneal mesothelioma (MCPM) is an uncommon tumor of mesothelial origin, characterized by multiple interconnected cystic spaces and uncertain biological behavior. Although traditionally considered benign, its tendency to recur and occasionally spread within the peritoneal cavity challenges this perception. We describe a 32-year-old woman who experienced gradually worsening pelvic pain and a constant feeling of pressure, which intensified after childbirth. Imaging revealed a large multilocular cystic mass occupying the pelvis. At laparotomy, a gelatinous, multilocular lesion was found adherent to the pelvic peritoneum, uterus, ovaries, and rectosigmoid colon. Complete cytoreductive surgery was performed, including pelvic peritonectomy, omentectomy, appendectomy, and resection of the affected serosa, followed by closed-abdomen hyperthermic intraperitoneal chemotherapy (HIPEC) with oxaliplatin (300 mg/m2, 42°C, 90 min). Histopathology confirmed benign multicystic mesothelioma with a mesothelial immunophenotype. The patient recovered well and remains disease-free at 6 months. MCPM requires complete cytoreduction, and HIPEC may help achieve lasting disease control.