Treatment of Malignant Peritoneal Mesothelioma (MESOTIP)

Primary Outcome Measures

1. Overall survival [ Time Frame: from randomization of first patient until the database cut-off ]The overall survival is defined as the time from the date of randomization to the date of death from any cause

Secondary Outcome Measures

1. Response to treatment using PFS [ Time Frame: week 10, week21,every 4 months during 2 years ]Progression free survival (PFS) defined as the time from the date of randomization to the date of any progression or death. PFS will be described with median PFS, 1 and 2y-PFS rate
   
2. Adverse event [ Time Frame: during treatment ]Safety according to CTCAE v5.0. Complications related to PIPAC will also be defined according to CTCAE v5.0 as recent publications in the field of peritoneal carcinomatosis suggest that this classification is more reliable when compared with the Clavien Dindo classification for the peritoneal carcinomatosis surgery
   
3. Feasibility of compliance [ Time Frame: Week 21 ]Feasibility rate of compliance defined as the percentage of patients who received 6 cycles of systemic chemotherapy and 4 PIPAC (for experimental arm).
   
4. Conversion to resectability [ Time Frame: surgery ]Conversion to resectability rate defined as the percentage of patients eligible for cytoreductive surgery and HIPEC at the end of the treatment out of the total number of patients. Patients are eligible for surgery if preservation of at least 1.5 m of small bowel and of at least 2 m of lower gastrointestinal tube is feasible in case of complete cytoreduction.
   
5. Quality of life evaluation [ Time Frame: baseline, week10, week21, FU every 4 months during 2 years ]Quality of life EORTC QLQ-C30 questionnaires according to EORTC Guidelines

Inclusion Criteria

1. Age ≥ 18 years
2. PS (or WHO) <2
3. Histologically-confirmed diagnosis of peritoneal malignant mesothelioma
4. No previous line of treatment (both medical and surgical oncologic treatments) for this disease
5. Peritoneal Carcinomatosis Index (PCI)>27 or at least 4 on the small bowel with serosal involvement contraindicating the cytoreductive surgery because of the impossibility to preserve a length >=1.5 m of uninvolved small bowel
6. Written and dated informed consent
7. Affiliated to the French national social security system

Exclusion Criteria

1. WHO performance status ≥ 2
2. Any contraindication to chemotherapy and/or radiotherapy
3. Any contraindication to repeated laparoscopy
4. Symptomatic cardiac or coronary insufficiency
5. Severe renal insufficiency
6. Progressive active infection or any other severe medical condition
7. Intestinal occlusion non responsive to medical treatment
8. Other cancer treated within the last 2 years except in situ cervical carcinoma or basocellular/spinocellular carcinoma
9. Pregnant or breast-feeding woman
10. Previously operated patients where laparoscopy is not feasible
11. Persons deprived of liberty or under guardianship or incapable of giving consent
12. Any psychological, familial, sociological or geographical condition potentially hampering compliance with the study protocol or follow-up schedule