@misc{oai:repo.qst.go.jp:00062996, author = {Tsuji, Hiroshi and Okada, Toru and Sugahara, Shinji and Serizawa, Itsuko and Kamada, Tadashi and Tsujii, Hirohiko and 辻 比呂志 and 岡田 徹 and 菅原 信二 and 芹澤 慈子 and 鎌田 正 and 辻井 博彦}, month = {Mar}, note = {Purpose: Analysis of the results of hypofractionated conformal carbon ion radiotherapy (C-ion RT) for localized prostate cancer was performed, with regard to normal tissue morbidity, biochemical relapse-free rate (bNED), and patient survival. Methods and Materials: Five hundreds and forty-two prostate cancer patients who received C-ion RT established through two preceding dose-escalation studies were analyzed in regard to toxicity, survival, and bNED. Results: Concerning radiation morbidity, no grade 3 or higher toxicities were observed either in the rectum or genitourinary system (GU), and the incidences of grade 2 rectum and GU morbidity were only 2.3% and 4.8%, respectively. The incidence of late GU toxicity in patients treated with 16 fractions of C-ion RT was lower than that of 20 fractions. Overall bNED at 5 years was 88.9%, with only four local recurrences. bNED of 16 fractions of C-ion RT was comparable to that of 20 fractions. Gleason's score, T-stage, and initial PSA were significant prognostic factors for bNED, and T-stage was also a significant prognostic factor for overall survival rate. The duration of hormonal therapy also had an impact on biochemical control in high-risk patients, but it appeared possible to apply C-ion RT with short-course hormonal therapy to intermediate-risk patients. Conclusion: C-ion RT with the established dose fractionation regimen yielded satisfactory bNED with very few local recurrences, and with minimal morbidity. C-ion RT of 16 fractions could offer even lower incidence of GU toxicity than that of 20 fractions., NIRS-ETOILE Joint Symposium 2009 on Carbon Ion Radiotherapy}, title = {Prostate Cancer}, year = {2009} }