Purpose: The aim of this retrospective study was to present the prevalence of early and late radiation-induced reaction and factors affecting its formation and severity in patients after adjuvant radio- or radiochemotherapy in salivary gland cancer.
Material and methods: A total of 113 patients with early and 91 with late radiation-induced reaction, irradiated in 2006-2016 were enrolled in the study. The frequency of acute mucosal radiation-induced reaction, time of onset, intensity, healing time, as well as the incidence of late radiation-induced reaction from the skin and subcutaneous tissue were analyzed. Factors that could influence the development and intensity of reaction were identified.
Results: Acute severity and the presence of late radiation-induced reaction do not affect overall survival. Dosage in the tumor bed site, as well as the dosage in the nodal region, affect the severity of the acute radiation-induced mucosal reaction. The severity of the early radiation-induced reaction is higher in men, more advanced patients (higher T and N+ in TNM classification), irradiated into a larger area, and those in whom two-dimensional planning and complementary chemoradiotherapy were applied. The late reaction of the skin and subcutaneous tissue was dominated by patients irradiated in the nodal regions and those with a higher intensity of early radiation-induced reaction.
Conclusions: Supplementary radiotherapy or radiochemotherapy in salivary gland cancer is associated with acceptable toxicity which has no effect on overall survival.
Keywords: radiation-induced reaction; radiochemotherapy; radiotherapy; salivary gland tumours.