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Purpose: To determine the long-term results of carbon ion radiation therapy (C-ion RT) in patients with choroidal melanoma, and to assess the usefulness of CT-based 2-port irradiation in reducing the risk of neovascular glaucoma (NVG). Methods and Materials: Between January 2001 and February 2012, a total of 116 patients with locally advanced or unfavorably located choroidal melanoma received CT-based C-ion RT. Of these patients, 114 were followed up for more than 6 months and their data analyzed. The numbers of T3 and T2 patients (International Union Against Cancer [UICC], 5th edition) were 106 and 8, respectively. The total dose of C-ion RT varied from 60 to 85 GyE, with each dose given in 5 fractions. Since October 2005, 2-port therapy (51 patients) has been used in an attempt to reduce the risk of NVG. A dose-volume histogram analysis was also performed in 106 patients. Results: The median follow-up was 4.6 years (range, 0.5-10.6 years). The 5-year overall survival, cause-specific survival, local control, distant metastasis-free survival, and eye retention rates were 80.4% (95% confidence interval 89.0%-71.8%), 82.2% (90.6%-73.8%), 92.8% (98.5%-87.1%), 72.1% (81.9%-62.3%), and 92.8% (98.1%-87.5%), respectively. The overall 5-year NVG incidence rate was 35.9% (25.9%-45.9%) and that of 1-port group and 2-port group were 41.6% (29.3%-54.0%) and 13.9% (3.2%-24.6%) with statistically significant difference (P<.001). The dose-volume histogram analysis showed that the average irradiated volume of the iris-ciliary body was significantly lower in the non-NVG group than in the NVG group at all dose levels, and significantly lower in the 2-port group than in the 1-port group at high dose levels. Conclusions: The long-term results of C-ion RT for choroidal melanoma are satisfactory. CT-based 2-port C-ion RT can be used to reduce the high-dose irradiated volume of the iris-ciliary body and the resulting risk of NVG. [ABSTRACT FROM AUTHOR]

Background and purpose A multi-institutional observational study (J-CROS1501PR) has been carried out to analyze outcomes of carbon-ion radiotherapy (CIRT) for patients with prostate cancer. Patients and methods Data of the patients enrolled in prospective studies of following 3 CIRT institutions were analyzed: National Institute of Radiological Sciences (NIRS; Chiba, Japan), Gunma University Heavy Ion Medical Center (GHMC; Gunma, Japan), and Ion Beam Therapy Center, SAGA HIMAT Foundation (HIMAT; Saga, Japan). Endpoints of the clinical trial are biochemical recurrence-free survival (bRFS), overall survival (OS), cause-specific survival (CSS), local control rate (LCR), and acute/late adverse effects. Results A total of 2157 patients’ data were collected from NIRS ( n = 1432), GHMC ( n = 515), and HIMAT ( n = 210). The number of patients in low-risk, intermediate-risk, and high-risk groups was 263 (12%), 679 (31%), and 1215 (56%), respectively. The five-year bRFS in low-risk, intermediate-risk, and high-risk patients was 92%, 89%, and 92%, respectively. The five-year CSS in low-risk, intermediate-risk, and high-risk patients was 100%, 100%, and 99%, respectively. The incidence of grade 2 late GU/GI toxicities was 4.6% and 0.4%, respectively, and the incidence of ⩾G3 toxicities were 0%. Conclusions Favorable overall outcomes of CIRT for prostate cancer were suggested by the analysis of the first multi-institutional data. [ABSTRACT FROM AUTHOR]

Purpose The aim of this study was to clarify the incidence, clinical risk factors, and dose–volume relationship of upper gastrointestinal (GI) ulcer after carbon-ion radiotherapy (C-ion RT) for pancreatic cancer. Materials and methods Fifty-eight pancreatic cancer patients were treated with C-ion RT from April 2014 to December 2015. The total dose was 55.2 Gy (RBE) in 12 fractions. D 2cm3 of GI tracts were restricted under 46 Gy (RBE); RBE-weighted absorbed dose. The association between dosimetric parameters (V 10–50 , D max , D 1cm3 , D 2cm3 ) and GI ulcer was examined using Spearman’s correlation. The incidence of GI ulcer was compared between the two groups divided by the cutoff value. Results Twelve patients (21%) experienced gastric ulcer including only one (2%) grade 3 ulcer. There was no grade 4/5 toxicity or duodenal ulcer. V 10–30 was significantly associated with gastric ulcer. The 1-year estimated risk of gastric ulcer for the determined cutoff values were 51% vs. 10% (V 10 , ⩾102 cm 3 or less), 42% vs. 9% (V 20 , ⩾24 cm 3 or less), 34% vs. 4% (V 30 , ⩾6 cm 3 or less). Conclusions The incidence of GI ulcer after C-ion RT was very low with the dose constraint of D 2cm3 <46 Gy (RBE). To further minimize the risk of GI ulcer, V 10–30 should also be reduced. [ABSTRACT FROM AUTHOR]