* currently requiring mechanical ventilation * prior thoracic radiotherapy, with the exception of the following: 1. breast or post-mastectomy chest wall radiation (without regional nodal irradiation) may be included at the discretion of the site primary investigator, and 2. thoracic skin radiation therapy (without regional nodal irradiation) is allowed. * known hereditary syndrome with increased sensitivity to radiotherapy, including ataxia-telangiectasia, xeroderma pigmentosum, and nijmegen breakage syndrome * known prior systemic use of the following drugs: bleomycin, carmustine, methotrexate, busulfan, cyclophosphamide, or amiodarone * history of or current diagnosis of pulmonary fibrosis, or an alternative pulmonary condition responsible for significant lung compromise at the discretion of the site primary investigator * history of lung lobectomy or pneumonectomy * known history of pulmonary sarcoidosis, wegener's granulomatosis, systemic lupus erythematosus, rheumatoid arthritis, systemic sclerosis, polymyositis/dermatomyositis, sjögren's syndrome, mixed connective tissue disease, churg-strauss syndrome, goodpasture's syndrome, or ankylosing spondylitis. * symptomatic congestive heart failure within the past 6 months including during current hospitalization * history of recent or current malignancy receiving any cytotoxic chemotherapy or immunotherapy within the past 6 months. * history of bone marrow transplantation. * history of any solid organ transplant (renal, cardiac, liver, lung) requiring immunosuppressive therapy. * females who are pregnant or breast feeding. * inability to undergo radiotherapy for any other medical or cognitive issues.

* currently requiring mechanical ventilation * prior thoracic radiotherapy, with the exception of the following: 1. breast or post-mastectomy chest wall radiation (without regional nodal irradiation) may be included at the discretion of the site primary investigator, and 2. thoracic skin radiation therapy (without regional nodal irradiation) is allowed. * known hereditary syndrome with increased sensitivity to radiotherapy, including ataxia-telangiectasia, xeroderma pigmentosum, and nijmegen breakage syndrome * known prior systemic use of the following drugs: bleomycin, carmustine, methotrexate, busulfan, cyclophosphamide, or amiodarone * history of or current diagnosis of pulmonary fibrosis, or an alternative pulmonary condition responsible for significant lung compromise at the discretion of the site primary investigator * history of lung lobectomy or pneumonectomy * known history of pulmonary sarcoidosis, wegener's granulomatosis, systemic lupus erythematosus, rheumatoid arthritis, systemic sclerosis, polymyositis/dermatomyositis, sjögren's syndrome, mixed connective tissue disease, churg-strauss syndrome, goodpasture's syndrome, or ankylosing spondylitis. * symptomatic congestive heart failure within the past 6 months including during current hospitalization * history of recent or current malignancy receiving any cytotoxic chemotherapy or immunotherapy within the past 6 months. * history of bone marrow transplantation. * history of any solid organ transplant (renal, cardiac, liver, lung) requiring immunosuppressive therapy. * females who are pregnant or breast feeding. * inability to undergo radiotherapy for any other medical or cognitive issues.

currently requiring mechanical ventilation prior thoracic radiotherapy, with the exception of the following: breast or post-mastectomy chest wall radiation (without regional nodal irradiation) may be included at the discretion of the site primary investigator, and thoracic skin radiation therapy (without regional nodal irradiation) is allowed. known hereditary syndrome with increased sensitivity to radiotherapy, including ataxia-telangiectasia, xeroderma pigmentosum, and nijmegen breakage syndrome known prior systemic use of the following drugs: bleomycin, carmustine, methotrexate, busulfan, cyclophosphamide, or amiodarone history of or current diagnosis of pulmonary fibrosis, or an alternative pulmonary condition responsible for significant lung compromise at the discretion of the site primary investigator history of lung lobectomy or pneumonectomy known history of pulmonary sarcoidosis, wegener's granulomatosis, systemic lupus erythematosus, rheumatoid arthritis, systemic sclerosis, polymyositis/dermatomyositis, sjögren's syndrome, mixed connective tissue disease, churg-strauss syndrome, goodpasture's syndrome, or ankylosing spondylitis. symptomatic congestive heart failure within the past 6 months including during current hospitalization history of recent or current malignancy receiving any cytotoxic chemotherapy or immunotherapy within the past 6 months. history of bone marrow transplantation. history of any solid organ transplant (renal, cardiac, liver, lung) requiring immunosuppressive therapy. females who are pregnant or breast feeding. inability to undergo radiotherapy for any other medical or cognitive issues.

currently requiring mechanical ventilation prior thoracic radiotherapy, with the exception of the following: breast or post-mastectomy chest wall radiation (without regional nodal irradiation) may be included at the discretion of the site primary investigator, and thoracic skin radiation therapy (without regional nodal irradiation) is allowed. known hereditary syndrome with increased sensitivity to radiotherapy, including ataxia-telangiectasia, xeroderma pigmentosum, and nijmegen breakage syndrome known prior systemic use of the following drugs: bleomycin, carmustine, methotrexate, busulfan, cyclophosphamide, or amiodarone history of or current diagnosis of pulmonary fibrosis, or an alternative pulmonary condition responsible for significant lung compromise at the discretion of the site primary investigator history of lung lobectomy or pneumonectomy known history of pulmonary sarcoidosis, wegener's granulomatosis, systemic lupus erythematosus, rheumatoid arthritis, systemic sclerosis, polymyositis/dermatomyositis, sjögren's syndrome, mixed connective tissue disease, churg-strauss syndrome, goodpasture's syndrome, or ankylosing spondylitis. symptomatic congestive heart failure within the past 6 months including during current hospitalization history of recent or current malignancy receiving any cytotoxic chemotherapy or immunotherapy within the past 6 months. history of bone marrow transplantation. history of any solid organ transplant (renal, cardiac, liver, lung) requiring immunosuppressive therapy. females who are pregnant or breast feeding. inability to undergo radiotherapy for any other medical or cognitive issues.

- currently requiring mechanical ventilation - prior thoracic radiotherapy, with the exception of the following: 1. breast or post-mastectomy chest wall radiation (without regional nodal irradiation) may be included at the discretion of the site primary investigator, and 2. thoracic skin radiation therapy (without regional nodal irradiation) is allowed. - known hereditary syndrome with increased sensitivity to radiotherapy, including ataxia-telangiectasia, xeroderma pigmentosum, and nijmegen breakage syndrome - known prior systemic use of the following drugs: bleomycin, carmustine, methotrexate, busulfan, cyclophosphamide, or amiodarone - history of or current diagnosis of pulmonary fibrosis, or an alternative pulmonary condition responsible for significant lung compromise at the discretion of the site primary investigator - history of lung lobectomy or pneumonectomy - known history of pulmonary sarcoidosis, wegener's granulomatosis, systemic lupus erythematosus, rheumatoid arthritis, systemic sclerosis, polymyositis/dermatomyositis, sjögren's syndrome, mixed connective tissue disease, churg-strauss syndrome, goodpasture's syndrome, or ankylosing spondylitis. - symptomatic congestive heart failure within the past 6 months including during current hospitalization - history of recent or current malignancy receiving any cytotoxic chemotherapy or immunotherapy within the past 6 months. - history of bone marrow transplantation. - history of any solid organ transplant (renal, cardiac, liver, lung) requiring immunosuppressive therapy. - females who are pregnant or breast feeding. - inability to undergo radiotherapy for any other medical or cognitive issues.

- currently requiring mechanical ventilation - prior thoracic radiotherapy, with the exception of the following: 1. breast or post-mastectomy chest wall radiation (without regional nodal irradiation) may be included at the discretion of the site primary investigator, and 2. thoracic skin radiation therapy (without regional nodal irradiation) is allowed. - known hereditary syndrome with increased sensitivity to radiotherapy, including ataxia-telangiectasia, xeroderma pigmentosum, and nijmegen breakage syndrome - known prior systemic use of the following drugs: bleomycin, carmustine, methotrexate, busulfan, cyclophosphamide, or amiodarone - history of or current diagnosis of pulmonary fibrosis, or an alternative pulmonary condition responsible for significant lung compromise at the discretion of the site primary investigator - history of lung lobectomy or pneumonectomy - known history of pulmonary sarcoidosis, wegener's granulomatosis, systemic lupus erythematosus, rheumatoid arthritis, systemic sclerosis, polymyositis/dermatomyositis, sjögren's syndrome, mixed connective tissue disease, churg-strauss syndrome, goodpasture's syndrome, or ankylosing spondylitis. - symptomatic congestive heart failure within the past 6 months including during current hospitalization - history of recent or current malignancy receiving any cytotoxic chemotherapy or immunotherapy within the past 6 months. - history of bone marrow transplantation. - history of any solid organ transplant (renal, cardiac, liver, lung) requiring immunosuppressive therapy. - females who are pregnant or breast feeding. - inability to undergo radiotherapy for any other medical or cognitive issues.