The Evaluation and Management of Visceral Complications in Radiation Fibrosis Syndrome Part 1

External beam ionizing radiation is a fundamental component of cancer treatment and is incorporated into approximately 50% of cancer treatments. Radiation therapy causes cell death directly by apoptosis and indirectly by disruption of mitosis. Purpose of Review: This study aims to inform rehabilitation clinicians of the visceral toxicities of radiation fibrosis syndrome and how to detect and diagnose these complications. Recent Findings: Latest research indicates that radiation toxicity is primarily related to radiation dose, patient co-morbidity, and concomitant use of chemotherapies and immunotherapies for the treatment of cancer. While cancer cells are the primary target, surrounding normal cells and tissues are also affected. Radiation toxicity is dose dependent, and tissue injury develops from inflammation that may progress to fibrosis. Thus, radiation dosing in cancer therapy is often limited by tissue toxicity. Although newer radiotherapeutic modalities aim to limit delivery of radiation to non-cancerous tissues, many patients continue to experience toxicity. Summary: To ensure early recognition of radiation toxicity and fibrosis, it is imperative that all clinicians are aware of the predictors, signs, and symptoms of radiation fibrosis syndrome. Here, we present part 1 of the visceral complications of radiation fibrosis syndrome, addressing radiation-related toxicity in the heart, lungs, and thyroid gland.