Relative Safety of External Beam Radiation Therapy in Lung Transplant Recipients Who Develop Thoracic Malignancies

We report outcomes for three patients who previously received lung transplants, subsequently developed malignancies, and were given radiation therapy to the chest for treatment of their cancers despite lack of scientific data on radiation tolerance of transplanted lung. None of three patients exhibited early or delayed adverse reactions to radiotherapy. For these three cases, the mean dose to the ipsilateral transplanted lung was 10 Gy, and ipsilateral lung relative volume of lung receiving 20 Gy or more was, on average, 22%. These doses are relatively low and would have been considered safe for patients with native lungs. In our opinion, tolerance of transplanted lung to therapeutic radiotherapy clearly requires additional research. While those data are pending, radiation therapy to the thorax should not be ruled out on the basis of having a lung transplant alone, provided lung dose can be maintained as low as possible using meticulous treatment planning.