BackgroundWe examined the efficacy and toxicity of proton beam therapy (PBT) for treating advanced cholangiocarcinoma.MethodsThe clinical data and outcomes of 28 cholangiocarcinoma patients treated with PBT between January 2009 and August 2011 were retrospectively examined. The Kaplan–Meier method was used to estimate overall survival (OS), progression-free survival (PFS), and local control (LC) rates, and the log-rank test to analyze the effects of different clinical and treatment variables on survival. Acute and late toxicities were assessed using the National Cancer Institute Common Terminology Criteria for Adverse Events version 4.0.ResultsThe median age of the 17 male and 11 female patients was 71 years (range, 41 to 84 years; intrahepatic/peripheral cholangiocarcinoma, n = 6; hilar cholangiocarcinoma/Klatskin tumor, n = 6; distal extrahepatic cholangiocarcinoma, n = 3; gallbladder cancer, n = 3; local or lymph node recurrence, n = 10; size, 20–175 mm; median 52 mm). The median radiation dose was 68.2 Gy (relative biological effectiveness [RBE]) (range, 50.6 to 80 Gy (RBE)), with delivery of fractions of 2.0 to 3.2 Gy (RBE) daily. The median follow-up duration was 12 months (range, 3 to 29 months). Fifteen patients underwent chemotherapy and 8 patients, palliative biliary stent placement prior to PBT. OS, PFS, and LC rates at 1 year were 49.0%, 29.5%, and 67.7%, respectively. LC was achieved in 6 patients, and was better in patients administered a biologically equivalent dose of 10 (BED10) > 70 Gy compared to those administered < 70 Gy (83.1% vs. 22.2%, respectively, at 1 year). The variables of tumor size and performance status were associated with survival. Late gastrointestinal toxicities grade 2 or greater were observed in 7 patients <12 months after PBT. Cholangitis was observed in 11 patients and 3 patients required stent replacement.ConclusionsRelatively high LC rates after PBT for advanced cholangiocarcinoma can be achieved by delivery of a BED10 > 70 Gy. Gastrointestinal toxicities, especially those of the duodenum, are dose-limiting toxicities associated with PBT, and early metastatic progression remains a treatment obstacle.

PBT-IACT for stage III-IVB tongue cancer has an acceptable toxicity profile and showed good treatment results. This protocol should be considered as a treatment option for locally advanced tongue cancer.

respectively. There were no significant differences in outcomes between the two protocols. Late grade 2 and 3 pulmonary toxicities were observed in nine patients (13.4%) and one patient (1.5%), respectively; no grade 4 or 5 toxicities were observed. Sex, age, performance status, T-stage, operability, and tumor pathology were not associated with OS and PFS.Only maximum standardized uptake value (SUV max ;  5 vs.  5) was identified as a significant prognostic factor for OS and PFS. conclusion. Both high-dose PBT protocols achieved high LC rates with tolerable toxicities in stage I NSCLC patients, and SUV max was a significant prognostic factor.

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position of the inhomogeneity. Margins for range uncertainties due the CT number variations were not considered in this study so as to focus only on the range changes caused by the displacement of inhomogeneity. An expanded or contracted contour of the high density or low density object was created by adding or subtracting 3 mm margin, respectively to the actual contours of the inhomogeneities (blurred image set). A single field optimization plan was created both in the original and blurred image sets for SSPBT. The robustness of these three plans for distal target coverage for up to 3 mm changes in the inhomogeneity position were studied. Results: The treatment plans for the SSPBT using the blurred image set showed similar robustness as the PSPBT plan with compensator smearing for dose coverage of the distal edge of the target. On the other hand, the distal target coverage in the treatment plan for the SSPBT, that used the image set without inhomogeneity blurring, was reduced when the location of the beam isocenter was changed, making the plan less robust compared to the PSPBT plan. Conclusions: The use of an expanded or contracted margin around high or low density objects in the images, respectively for SSPBT planning appears to be equivalent to the compensator smearing effect in PSPBT planning. Results of application of the proposed approach for designing treatment plans for SSPBT for prostate and targets in brain will be presented.