Purpose: To develop efficient predictive method for risk of dysuria after radiotherapy (RT). Patients and Methods: A total of 197 prostate cancer patients who underwent C-ion RT at a total dose of 64.4 +/- 2.7 GyE and evaluated for urinary morbidity (dysuria) according to the Late Effects of Normal Tissue/Subjective, Objective, Management, and Analytic scoring system (LENTSOMA). Three hundred seventy-three SNPs in 109 candidate genes were genotyped by MassARRAY system. Patients were categorized into control (grade 0) and case (grade >1) groups. First, association between the genotype at each SNP site and dysuria were assessed using the Fisher exact test (P ) had 3 or more risk genotypes. Conclusions: Although more patients are required to validate the results, this study supports the assumptions that radiosensitivity is caused by multigenetic factors and that the number of high-risk genotypes on SNPs might predict radiosensitivity.The 13th International Congress of Radiation Researc
