Predictors of Late Severe Radiotherapy-Related Toxic Reactions The aim of this study was to determine the predictors of radiotherapy-related late severe toxic reactions after hyperfractionated radiotherapy (with or without combined cisplatin chemotherapy) in patients with advanced localized head and neck tumors. Ghadjar P et al from Sweden published the study in the August issue of Radiother Oncol. Patient data were obtained from the clinical randomized phase III study SAKK10/94.Late severe radiotherapy-related toxic reactions were defined as grade 3 or higher RTOGs after 3 months from the end of radiotherapy and/or treatment-related deaths within 3 years. A total of 230 patients were included in the study, of whom 39% developed late severe chemotherapy-related toxic reactions. The median follow-up in this study was 9.7 years. Univariate Cox risk-proportional models showed the following factors to be associated with late severe radiotherapy-related toxic reactions: advanced tumor N-stage, lesions that could not be removed via surgery, percentage of body weight loss, supportive measures, and acute severe dysphagia. In subsequent multivariate analyses, the predictive effect of variables other than supportive measures on toxic responses remained statistically significant. Chemotherapy did not affect late severe toxic responses after radiotherapy, but high N stage, inoperable resectable tumors, proportion of weight loss, and severe acute dysphagia were independent predictors of late radiotherapy-related toxic responses.