Carbon Ion Radiotherapy in Advanced Hypofractionated Regimens for Prostate Cancer: From 20 to 16 Fractions

• Published in: International journal of radiation oncology, biology, physics Vol. 84; no. 4; pp. 968 - 972
• Main Authors: Okada, Tohru, MD, PhD, Tsuji, Hiroshi, MD, PhD, Kamada, Tadashi, MD, PhD, Akakura, Koichiro, MD, PhD, Suzuki, Hiroyoshi, MD, PhD, Shimazaki, Jun, MD, PhD, Tsujii, Hirohiko, MD, PhD
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier Inc 15.11.2012; Elsevier
• Subjects: Adenocarcinoma - blood; Adenocarcinoma - mortality; Adenocarcinoma - pathology; Adenocarcinoma - radiotherapy; Aged; Aged, 80 and over; Biological and medical sciences; Carbon; Carbon - adverse effects; Carbon - therapeutic use; Carbon ion radiotherapy; CARBON IONS; DISEASE INCIDENCE; Dose Fractionation; FRACTIONATED IRRADIATION; Gynecology. Andrology. Obstetrics; Heavy Ion Radiotherapy - adverse effects; Heavy Ion Radiotherapy - methods; Hematology, Oncology and Palliative Medicine; Humans; Hypofractionation; Male; Male genital diseases; Medical sciences; Middle Aged; Neoplasm Staging; NEOPLASMS; Nephrology. Urinary tract diseases; PATIENTS; PROSTATE; Prostate cancer; Prostate-Specific Antigen - blood; Prostatic Neoplasms - blood; Prostatic Neoplasms - mortality; Prostatic Neoplasms - pathology; Prostatic Neoplasms - radiotherapy; RADIATION DOSES; Radiation Injuries - pathology; Radiology; RADIOLOGY AND NUCLEAR MEDICINE; RADIOTHERAPY; Rectum - radiation effects; Retrospective Studies; Survival Rate; TOXICITY; Tumors; Tumors of the urinary system; Urinary tract. Prostate gland; Urogenital System - radiation effects; Hypofractionation; Prostate cancer; Carbon ion radiotherapy; Urinary system disease; Prostate disease; Malignant tumor; Radiotherapy; Carbon; Fractionated dose; Cancerology; Treatment; Advanced stage; Therapeutic protocol; Male genital diseases; Cancer
• ISSN: 0360-3016; 1879-355X
• DOI: 10.1016/j.ijrobp.2012.01.072

Purpose To assess the effects of differences in dose fractionation on late radiation toxicity and biochemical control in patients with prostate cancer treated with carbon ion radiotherapy (C-ion RT). Methods and Materials A total of 740 prostate cancer patients who received C-ion RT between April 2000 and February 2009 were analyzed. Of those, 664 patients followed for at least 1 year were analyzed with regard to late radiation toxicity. Biochemical relapse-free (BRF) and overall survival (OS) rates in patient subgroups with each dose-fractionation were analyzed. Results Only 1 case of grade 3 genitourinary (GU) morbidity was observed in 20 fractions, and none of the patients developed higher grade morbidities. The incidence of late GU toxicity in patients treated with 16 fractions was lower than that of patients treated with 20 fractions. The OS rate and BRF rate of the entire group at 5 years were 95.2% and 89.7%, respectively. The 5-year BRF rate of the patients treated with 16 fractions of C-ion RT (88.5%) was comparable to that of the patients treated with 20 fractions (90.2%). Conclusion C-ion RT of 57.6 GyE (the physical C-ion dose [Gy] × RBE) in 16 fractions could offer an even lower incidence of genitourinary toxicity and comparable BRF rate than that in 20 fractions. Advancement in hypofractionation could be safely achieved with C-ion RT for prostate cancer.