Search

Highlights • We analyzed 224 LRRC patients treated with C-ion RT at three institutions. • The median follow-up period from the initiation of C-ion RT was 62 months. • The OS rates were 73% at 3 years and 51% at 5 years. • Grade 3 acute (n = 3) and grade 3 late (n = 12) toxicity was observed. • C-ion RT for LRRC showed relatively favorable outcomes and limited toxicity. Abstract Purpose We investigated the efficacy and safety of carbon-ion radiotherapy (C-ion RT) for locally recurrent rectal cancer (LRRC). Patients and methods Data from patients with LRRC treated with C-ion RT from November 2003 to December 2014 at three institutions were retrospectively analyzed. The endpoints of this clinical trial were overall survival (OS), local control (LC), and acute/late toxicity. Results A total of 224 patients' data were collected. The prescribed dose was 70.4 Gy (relative biological effectiveness [RBE]-weighted absorbed dose) or 73.6 Gy (RBE) in 16 fractions. The median follow-up period from the initiation of C-ion RT was 62 months (range 6–169 months). The OS rates were 73% (95% confidence interval [CI], 67%–79%) at 3 years and 51% (95%CI 44%–58%) at 5 years. The LC rates were 93% (95%CI 88%–96%) at 3 years, and 88% (95%CI 82%–93%) at 5 years. Grade 3 acute toxicity was observed in three patients: gastrointestinal toxicity (n = 1) and pelvic infection (n = 2). Grade 3 late toxicity was observed in 12 patients: skin reaction (n = 2), gastrointestinal toxicity (n = 2), neuropathy (n = 1), and pelvic infection (n = 7). There was no grade 4 or 5 acute or late toxicity. Conclusions This first multi-institutional analysis of C-ion RT for LRRC indicated relatively favorable outcomes with limited toxicities. [ABSTRACT FROM AUTHOR]

Highlights • We analyzed 64 LAPC patients treated with C-ion RT at single institution. • The median survival time and 2-year OS were 25.1 months and 53%. • Only four patients experienced acute grade 3 toxicities. • C-ion RT for LAPC showed relatively favorable outcome and limited toxicity. Abstract Purpose The aim of this study was to evaluate the efficacy and safety of carbon-ion radiotherapy (C-ion RT) for unresectable locally advanced pancreatic cancer (LAPC). Methods and materials Patients with LAPC treated with definitive C-ion RT between April 2014 and July 2017 were analyzed retrospectively. The prescribed dose was 55.2 Gy (relative biological effectiveness [RBE] weighted absorbed dose) in 12 fractions. Overall survival (OS), local control (LC), progression free survival (PFS), and toxicity were evaluated. Results Sixty-four patients were enrolled. All patients completed planned course of C-ion RT. The median follow-up time for survivors from the initiation of C-ion RT was 24.4 months (range, 5.1–46.1 months). Median survival time was 25.1 months. Two-year OS, LC, and PFS were 53% (95% confidence interval [CI], 39%–66%), 82% (95% CI, 66%–91%), and 23% (95% CI, 14%–36%), respectively. Four patients experienced acute grade 3 toxicities including 3 gastrointestinal (GI) toxicities. There was no grade 3 or more late toxicity. Conclusions The clinical results of C-ion RT for LAPC at our institution were comparable to those of a recent multi-institutional analysis. [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]

BACKGROUND: The authors evaluated the tolerance and efficacy of carbon-ion radiotherapy (CIRT) as a short-course, preoperative treatment and determined the recommended dose needed to reduce the risk of postoperative local recurrence without excess injury to normal tissue. METHODS: Patients radiographically defined with potentially resectable pancreatic cancer were eligible. A preoperative, short-course, dose-escalation study was performed with fixed 8 fractions in 2 weeks. The dose of irradiation was increased by 5% increments from 30 grays equivalents (GyE) to 36.8 GyE. Surgery was to be performed 2 to 4 weeks after the completion of CIRT. RESULTS: The study enrolled 26 patients. At the time of restaging after CIRT, disease progression with distant metastasis or refusal ruled out 5 patients from surgery. Twenty-one of 26 patients (81%) patients underwent surgery. The pattern of initial disease progression was distant metastasis in 17 patients (65%) and regional recurrence in 2 patients (8%). No patients experienced local recurrence. The 5-year survival rates for all 26 patients and for those who underwent surgery were 42% and 52%, respectively. CONCLUSIONS: Preoperative, short-course CIRT followed by surgery is feasible and tolerable without unacceptable morbidity. Cancer 2013. © 2012 American Cancer Society. [ABSTRACT FROM AUTHOR]

Purpose To compare carbon-ion beam dose distribution between passive and scanning radiation therapies for locally advanced pancreatic cancer. Materials and methods Thirteen pancreatic cancer patients were included in this study. Four types of treatment planning with respiratory gating were calculated for each patient: a four-field box with passive irradiation (Plan 1), scanning irradiation (Plan 2), a three-field (150°, 180° and 210°) protocol with passive irradiation (Plan 3), and scanning irradiation (Plan 4). The irradiation plans each delivered 55.2 Gy (RBE) to the planning target volume (PTV) and were compared with respect to doses to the PTV and organs at risk (OARs). Results Plan 3 exceeded the dose assessment metrics to the spinal cord. Scanning irradiation plans (Plan 2 and, particularly, Plan 4) offered significantly reduced dosage to the stomach and the duodenum compared with passive irradiation. Conclusion Three-field oblique scanning irradiation for pancreatic cancer has the potential to reduce gastrointestinal exposure and influence of peristalsis on dose distribution. [ABSTRACT FROM AUTHOR]

• The establishment of an optimal, effective, and safe CIRT protocol for SNMM is crucial. • The CTV designs and doses for SNMM were investigated in this study. • Extended CTV was observed to be appropriate for CIRT of SNMM. • At least 40 Gy to the subclinical region was recommended. No guidelines exist for the clinical target volume (CTV) and radiotherapy dose in sinonasal mucosal melanoma (SNMM). Thus, we aimed to determine the carbon-ion radiotherapy (CIRT) CTV and dose for SNMM. In total, 135 patients with SNMM who received CIRT were reviewed. The relative biological effectiveness-weighted dose was 57.6 or 64 Gy in 16 fractions. CTV was classified into small CTV, which included the gross tumor and visible melanosis with a certain margin, and extended CTV, which included the tumor site and adjacent anatomical structures. Local recurrence (LR) patterns were pattern I, II, and III, defined as recurrence over the gross tumor, visible melanosis and subclinical area, which would be covered if extended CTV was applied, and outside the extended CTV, respectively. The 5-year LR rate was 35.3 %. The prescribed dose was not a significant risk factor for pattern I LR; however, 57.6 Gy for a large tumor was insufficient for local control. Using an extended CTV was significantly associated with a lower risk of pattern II LR, and these recurrences did not occur in regions that received > 40 Gy. The 5-year pattern III LR rate was 6.4 %. Utilizing an extended CTV in CIRT for SNMM is appropriate even for small tumors. Using a smaller CTV after an extended CTV of at least 40 Gy is recommended to reduce adverse events. Although the optimal dose for gross tumors remains unclear, the latest technology with 64 Gy showed good outcomes. [ABSTRACT FROM AUTHOR]

• We confirmed the safety and efficacy of a novel CIRT with LET optimization for head and neck cancer. • To achieve this, we employed LET painting technique. • This is the first study to assess CIRT with LET optimization for clinical application. This feasibility study confirmed the initial safety and efficacy of a novel carbon-ion radiotherapy (CIRT) using linear energy transfer (LET) painting for head and neck cancer. This study is the first step toward establishing CIRT with LET painting in clinical practice and making it a standard practice in the future. [ABSTRACT FROM AUTHOR]