Long-term regional chemotherapy for patients with epithelial malignant peritoneal mesothelioma results in improved survival.

PURPOSE: Malignant peritoneal mesothelioma (MPM) is a rare disease with about 300 new cases per year in the USA. Its natural history is described as local progression within the peritoneal space in the absence of liver metastases or systemic disease.

METHODS: Cytoreductive surgery (CRS) is a series of peritonectomy procedures and visceral resections with a goal of complete removal of all visible disease from the abdomen and pelvis. Over 20 years, three protocols investigating increasing efficacy of additional chemotherapy treatments added to CRS have been initiated. Initially, hyperthermic perioperative chemotherapy (HIPEC) with doxorubicin and cisplatin was used in the operating room. Then, early postoperative intraperitoneal chemotherapy (EPIC) with paclitaxel was added for the first 5 days after CRS. The third protocol employed HIPEC, then EPIC, and then long-term intraperitoneal (IP) paclitaxel or IP pemetrexed plus intravenous (IV) cisplatin as a adjuvant normothermic intraperitoneal chemotherapy (NIPEC).

RESULT: The 5-year survival of 42 patients treated with CRS and HIPEC was 44%, for 58 patients treated with EPIC and HIPEC was 52% and 29 patients who received HIPEC, EPIC, and NIPEC was 75% (p = 0.0374). Prognostic variables of age, gender, treatment administered, peritoneal cancer index (PCI) and completeness of cytoreduction were significant by univariate analysis and treatments administered and completeness of cytoreduction significant by multivariate analysis.

CONCLUSIONS: Long-term regional chemotherapy was associated with improved survival in patients with MPM. In this rare disease, additional phase 2 investigations are suggested.