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Summary: The prognosis of high-risk prostate cancer is poor with a high mortality rate. The Radiation Therapy Oncology Group (RTOG) has performed dose-escalation studies of external beam radiation therapy (EBRT) and has developed high-precision radiation therapy (RT) methods such as intensity-modulated RT, carbon ion therapy, and proton beam therapy. High-dose rate brachytherapy (HDR-BT) is also studied as an option for high-risk prostate cancer treatment. Past clinical trials have suggested that the local control rate of high-risk prostate cancer improves with total EBRT dose, even for doses >70Gy. Several randomized controlled trials, including RTOG 94-06, have shown significantly better prognoses with higher doses (>75Gy) than with lower doses (<70Gy). A proton beam therapy trial (PROG 95–09) also showed similar results. A phase II clinical trial (National Institute for Radiological Sciences, Japan; trial 9904) showed that carbon ion therapy resulted in very good biochemical recurrence-free survival rates among high-risk prostate cancer patients, demonstrating particle therapy to be a valid treatment option. RTOG 86-10 showed that short-term neo-adjuvant hormonal therapy (HT) was inadequate for high-risk prostate cancer but effective for intermediate-risk prostate cancer, whereas RTOG 92-02 and the European Organisation for Research and Treatment of Cancer (EORTC) 22863 showed significant improvements in the prognosis of high-risk groups receiving long-term (>2years) HT combined with definitive RT. Further studies are warranted to elucidate optimal irradiation doses, HT treatment durations, and combination therapy schedules. [Copyright &y& Elsevier]

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]

Purpose To evaluate the applicability of carbon ion beams for the treatment of carcinoma of the lacrimal gland with regard to normal tissue morbidity and local tumor control. Methods and materials Between April 2002 and January 2011, 21 patients with locally advanced primary epithelial carcinoma of the lacrimal gland were enrolled in a Phase I/II clinical trial of carbon-ion radiotherapy (CIRT) at the National Institute of Radiological Sciences. Acute radiation toxicity was the primary endpoint of this dose-escalation study and the late toxicity, local control, and overall survival were additionally evaluated as secondary endpoints. Of the 21 subjects enrolled, all patients were followed for more than 6 months and analyzed. Results The radiation dose was increased from the initial dose of 48.0 Gy equivalents (GyE)/12 fractions at 10% increments up to 52.8 GyE. Of the 21 patients, five received a total dose of 48.0 GyE, and 16 received a total dose of 52.8 GyE. No patient developed grade 3 or higher skin toxicity. As late ocular/visual toxicity, three patients had grade 3 retinopathy and seven patients lost their vision. Among the 10 patients treated until May 2005, five patients had local recurrence, three of whom had marginal recurrence. Therefore, the margin for the CTV (clinical target volume) was set to a range according to the orbital exenteration since June 2005. After the application of the extended margin, no local recurrence has been observed. The three-year overall survival and local control rates were 82.2% and 79.0%, respectively. Conclusion CIRT can be applied for primary epithelial carcinoma of the lacrimal gland, with a borderline acceptable morbidity and sufficient antitumor effect when an extended margin is adopted. [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]