Radiotherapy and immune suppression: A short review

The management of patients undergoing immunosuppressive agents is really challenging. Based on precaution principle, it seems mandatory to stop immunosuppressive (or immunomodulating) agents during radiation. Yet, it is impossible in grafted patients. It is possible in patients with autoimmune disease, but in this case, the autoimmune disease might modify patient's radiosensitivity. We provide a short review about the safety of radiotherapy in grafted/auto-immune patients. The literature is limited with data coming from outdated case-report or case-control studies. It seems that radiotherapy is feasible in grafted patients, but special dose-constraints limitations must probably be considered for the transplant and the other organs at risk. There is very little data about the safety of radiotherapy, when associated with immunomodulating agents. The most studied drug is the methotrexate but only its prescription as a chemotherapy (high doses for a short period of time) was reported. When used as an immunomodulator, it should probably be stopped 4 months before and after radiation. Apart from rheumatoid arthritis, it seems that collagen vascular diseases and especially systemic scleroderma and systemic lupus erythematous feature increased radio-sensitivity with increased severe late toxicities. Transplanted patients and collagen vascular disease patients should be informed that there is very little data about safety of radiation in their case.