Keloids and Hypertrophie Scars. In: Seegenschmiedt MH, Makoski H, Trott K, Brady LW, editors. Radiotherapy for Non-Malignant Disorders. Berlin: Springer Berlin Heidelberg; 2008. pp. 209-24. [DOI: 10.1007/978-3-540-68943-0_11]

Basics of Radiation Biology When Treating Hyperproliferative Benign Diseases

For decades, low- and moderate-dose radiation therapy (RT) has been shown to exert a beneficial therapeutic effect in a multitude of non-malignant conditions including painful degenerative muscoloskeletal and hyperproliferative disorders. Dupuytren and Ledderhose diseases are benign fibroproliferative diseases of the hand/foot with fibrotic nodules and fascial cords, which determine debilitating contractures and deformities of fingers/toes, while keloids are exuberant scar formations following burn damage, surgery, and trauma. Although RT has become an established and effective option in the management of these diseases, experimental studies to illustrate cellular composites and factors involved remain to be elucidated. More recent findings, however, indicate the involvement of radiation-sensitive targets like mitotic fibroblasts/myofibroblasts as well as inflammatory cells. Radiation-related molecular mechanisms affecting these target cells include the production of free radicals to hamper proliferative activity and interference with growth factors and cytokines. Moreover, an impairment of activated immune cells involved in both myofibroblast proliferative and inflammatory processes may further contribute to the clinical effects. We here aim at briefly describing mechanisms contributing to a modulation of proliferative and inflammatory processes and to summarize current concepts of treating hyperproliferative diseases by low and moderate doses of ionizing radiation.

Radiotherapy for non-malignant disorders: state of the art and update of the evidence-based practice guidelines

Every year in Germany about 50,000 patients are referred and treated by radiotherapy (RT) for "non-malignant disorders". This highly successful treatment is applied only for specific indications such as preservation or recovery of the quality of life by means of pain reduction or resolution and/or an improvement of formerly impaired physical body function owing to specific disease-related symptoms. Since 1995, German radiation oncologists have treated non-malignant disorders according to national consensus guidelines; these guidelines were updated and further developed over 3 years by implementation of a systematic consensus process to achieve national upgraded and accepted S2e clinical practice guidelines. Throughout this process, international standards of evaluation were implemented. This review summarizes most of the generally accepted indications for the application of RT for non-malignant diseases and presents the special treatment concepts. The following disease groups are addressed: painful degenerative skeletal disorders, hyperproliferative disorders and symptomatic functional disorders. These state of the art guidelines may serve as a platform for daily clinical work; they provide a new starting point for quality assessment, future clinical research, including the design of prospective clinical trials, and outcome research in the underrepresented and less appreciated field of RT for non-malignant disorders.