3546 - Carbon-Ion Radiotherapy for Elderly Patients with Locally Advanced Pancreatic Cancer
Presenter(s)
K. Terashima, H. Suefuji, A. Matsunobu, S. Toyama, K. Fukunishi, W. Ohta, and Y. Shioyama; Ion Beam Therapy Center, SAGA HIMAT Foundation, Tosu, Japan
Purpose/Objective(s): Approximately 40% of patients diagnosed with pancreatic cancer are over the age of 75. Treatment of locally advanced pancreatic cancer (LAPC) in elderly patients is often challenging due to the high prevalence of comorbidities. The aim of this study is to evaluate the efficacy and safety of carbon-ion radiotherapy (CIRT) for elderly patients with LAPC.
Materials/Methods: We retrospectively analyzed patients aged 75 years or older with histologically confirmed LAPC who were treated with CIRT between January 2014 and April 2024. The prescribed dose was 55.2 Gy (RBE) in 12 fractions. The overall survival (OS), local control (LC), progression free survival (PFS), and treatment-related toxicity were evaluated.
Results: A total of 60 elderly patients were included in this analysis. The age range was 75-90 years (median 79 years). There were 32 male patients and 28 female patients. Tumor location was head in 28, and body-tail in 32. Median tumor size was 35mm (range 16-55 mm). 50 patients (83%) were received sequential and/or concurrent chemotherapy. All patients completed planned course of CIRT. The median follow-up time from the initiation of carbon-ion radiotherapy was 18 months (range: 3-74 months). The 1- and 2-year OS were 72.3% and 49.6%, respectively. The median survival time was 22.7 months. The 1- and 2-year PFS were 44.2% and 22.8%, respectively, with a median PFS of 10.0 months. The 1- and 2-year LC were 87.8% and 82.0 %, respectively. From the initiation of all treatments, 2-year OS was 53.6%. Six patients (10%) experienced grade 3 acute toxicities: hematologic toxicity in 5 patients and gastric ulcer/bleeding in 1 patient. The patients with grade 3 gastric ulcer/bleeding underwent blood transfusion and recovered quickly. There was no grade 4 or 5 acute toxicity. In terms of late toxicity, no grade 3 or higher toxicities were observed.
Conclusion: Even for elderly patients with locally advanced pancreatic cancer, CIRT appeared to be effective with acceptable toxicity.