CLINICAL TRIAL / NCT04158141

Inclusion Criteria: PRIOR TO STEP 1 REGISTRATION INCLUSION CRITERIA - Pathologically (histologically or cytologically) confirmed diagnosis of epithelioid or biphasic malignant pleural mesothelioma (MPM) within 90 days prior to Step 1 Registration - Imaging proof of clinical stage (American Joint Committee on Cancer [AJCC] 8th edition) I-IIIA MPM by PET/CT within 42 days prior to Step 1 Registration - MPM is amenable to resection by P/D as determined by a thoracic surgeon within 42 days prior to Step 1 Registration - History/physical examination within 42 days prior to Step 1 Registration - Karnofsky performance status >= 80 within 42 days prior to Step 1 Registration - Pulmonary function tests within 42 days prior to Step 1 Registration: - >= 40% predicted post-forced expiratory volume in 1 second (FEV1); - >= 40% predicted post-operative diffusion capacity of the lung for carbon monoxide (DLCO) (corrected for hemoglobin [Hgb]) - Leukocytes >= 3000 cells/mm^3 (within 30 days prior to Step 1 Registration) - Absolute neutrophil count >= 1500 cells/mm^3 (within 30 days prior to Step 1 Registration) - Platelets >= 100,000 cells/mm^3 (within 30 days prior to Step 1 Registration) - Serum total bilirubin =< 1.5 X upper limit of normal (ULN) (within 30 days prior to Step 1 Registration) - Aspartate aminotransferase (AST) (serum glutamic-oxaloacetic transaminase [SGOT]) and alanine aminotransferase (ALT) (serum glutamate pyruvate transaminase [SGPT]) =< 3.0 X ULN (within 30 days prior to Step 1 Registration) - Glomerular filtration rate (GFR): >= 50 mL/min/1.73 m^2 (must be calculated using estimated creatinine clearance [CrCl] by the Cockcroft-Gault [C-G] equation [Nephron 1976;16:31-41]) (within 30 days prior to Step 1 Registration) - Negative serum pregnancy test within 14 days of Step 1 Registration for pre-menopausal women of childbearing potential - The patient or a legally authorized representative must provide study-specific informed consent prior to study entry - EORTC QLQ-C30 and QLQ-LC13 within 42 days prior to Step 1 Registration PRIOR TO STEP 2 RANDOMIZATION INCLUSION CRITERIA - Patients must have received at least 2 cycles of pemetrexed/platinum chemotherapy and undergone a pleurectomy/decortication with the goal of macroscopic complete resection following step 1 Registration - Karnofsky performance status >= 70 within 30 days prior to Step 2 Randomization - History/physical examination within 30 days prior to Step 2 Randomization - EORTC QLQ-C30 and QLQ-LC13 within 30 days prior to Step 2 Randomization Exclusion Criteria: PRIOR TO STEP 1 REGISTRATION EXCLUSION CRITERIA - Pregnant or lactating women, or sexually active men or women not using effective contraception (risk for fetal defects from teratogenic chemotherapy and radiation therapy) within 14 days prior to Step 1 Registration - Diagnosis of sarcomatoid mesothelioma - Severe, active co-morbidity defined as follows: - New York Heart Association (NYHA) class III or IV heart failure - Chronic obstructive pulmonary disease (COPD) requiring chronic oral steroid therapy of > 10 mg prednisone daily or equivalent at the time of registration. Inhaled corticosteroids are allowed; - Unstable angina requiring hospitalization and/or transmural myocardial infarction within the last 3 months; - Interstitial lung disease; - Hemodialysis or peritoneal dialysis; - Concurrent active malignancy (with the exception of current or prior non-melanomatous skin cancer or low-grade malignancies followed observantly for which treatment has not or does not have the potential to interfere with the safety or efficacy assessment of the investigational regimen) - If evidence of disease < 3 years, institution must consult with the principal investigator, Andreas Rimner, Doctor of Medicine (MD) - Hepatic impairment defined by ChildPugh class (ChildPugh class B & C); - For patients with evidence of chronic hepatitis B virus (HBV) infection, the HBV viral load must be undetectable on suppressive therapy within 30 days prior to registration, if indicated. Note: HBV viral testing is not required for eligibility for this protocol - Patients with a history of hepatitis C virus (HCV) infection must have been treated and cured. For patients with HCV infection who are currently on treatment, they are eligible if they have an undetectable HCV viral load within 30 days prior to registration - Active tuberculosis - Patients on immunosuppressive therapy, for example history of organ or bone marrow transplant or chronic lymphocytic leukemia (CLL); - CD4 count < 200 cells/microliter. Note that patients who are human immunodeficiency virus (HIV) positive are eligible, provided they are under treatment with highly active antiretroviral therapy (HAART) and have a CD4 count >= 200 cells/microliter within 30 days prior to registration. Note also that HIV testing is not required for eligibility for this protocol - Prior nephrectomy on the contralateral side of MPM - Ipsilateral thoracic electronic implant, e.g. pacemaker, defibrillator, unless switched to the contralateral side prior to initiation of radiation therapy (RT) - Prior thoracic radiation therapy (patients with prior thoracic RT cannot be planned to 50-60 Gy without exceeding normal tissue constraints) PRIOR TO STEP 2 RANDOMIZATION EXCLUSION CRITERIA - Progressive disease - Supplemental oxygen use - Third space fluid that cannot be controlled by drainage or insufficient lung expansion after P/D (this prevents targeting the pleura without exceeding normal tissue constraints) - Prior intrapleural therapy (i.e. intrapleural chemotherapy, photodynamic therapy); pleurodesis is permitted - Bulky residual disease in the major fissure preventing pleural IMRT - Patients who have undergone extrapleural pneumonectomy - Patients with active infection that requires systemic I.V. antibiotics, antiviral, or antifungal treatments