[Prospective study of the pathology of radiation-induced mucositis]

One of the most severe early side effects of radiation in head and neck cancer patients is mucositis. Inflammation of the oral mucose may lead to an extreme subjective burden, restricting the patients' well-being and even leading to an interruption of radiotherapy. The aim of our prospective study was to investigate the pathological alterations of the oral mucosa during irradiation. Therefore, samples from head and neck cancer patients were taken before radiation and a 30-G and a 60-G radiation dose. Pathogenetic alterations were determined by immunohistochemical staining of various cell surface molecules known to be involved in the pathogenesis of inflammation. Staining was performed with antibodies against ICAM 1, VCAM 1, ELAM, 25F9, 27E10, and RM3-1. Our study demonstrates the expression rates of the various surface molecules during inflammation. Expression of RM3-1 and ICAM 1 showed a steep increase during the time of radiation, whereas expression of ELAM reached a low constant value. Therefore, we conclude that distinct cell surface molecules demonstrate a characteristic time-dependent expression during radiation. Better insight into the pathogenesis of radiation-induced mucositis may help to develop a pathological classification of mucositis and to improve therapeutic strategies.