Secondary Inflammatory Disorders After Radiotherapy

Radiotherapy (RT) is widely used in cutaneous oncology and increasingly combined with immunotherapy and targeted therapies. Beyond DNA damage, RT modulates the cutaneous immune microenvironment, contributing to both antitumour effects and inflammatory skin toxicities. While radiodermatitis is the most common reaction, RT may induce a broad spectrum of dermatoses, including postirradiation pseudosclerodermatous panniculitis, radiation-induced isotopic response, eosinophilic polymorphic pruritic eruption, and atypical vascular proliferations. Combined therapies further expand toxicity profiles. Recognition of this evolving spectrum is crucial for accurate diagnosis, timely management, and improved multidisciplinary care.