ESTRO meets Asia 2024 - Abstract Book

S278

Interdisciplinary – Upper GI

ESTRO meets Asia 2024

1 Radiation Oncology, All India Institute of Medical Sciences, Patna, India. 2 Radiation Oncology, All India Institute of medical Sciences, Patna, India

Purpose/Objective:

Gallbladder cancer (GBC) poses a significant global health threat, particularly in India's Indo-Gangetic belt. This study addresses the feasibility and outcomes of concurrent chemoradiation in locally advanced gall bladder cancer (LAGBC) who are unresectable and yet non metastatic in an attempt to consolidate local treatment when surgery seems remotely feasible.

Material/Methods:

Prospective observational study of LAGBC patients who were non metastatic on PET CT but unresectable. Treatment involved concurrent chemoradiotherapy with volumetric modulated arc therapy (VMAT) to a dose of 50.4 Gy to the planning target voulume (PTV) and capecitabine 825mg/m 2 twice daily throughout radiation. Patients were evaluated for hematological, gastrointestinal, hepatic and skin toxicity weekly during treatment and at one month thereafter. Toxicities were charted as per RTOG and EORTC criteria’s. Response was evaluated at one month following completion of treatment with contrast enhanced CT scan using RECIST version 1.1.

Results:

18 patients who fulfilled the eligibility criteria and gave consent were enrolled. RECIST response assessments showed a significant reduction in tumor size. Tumor marker (CA 19.9) levels decreased significantly post treatment. No significant hematoxicity, hepatotoxicity, and nephrotoxicity was seen. Duodenal doses were associated with upper gastrointestinal toxicity, emphasizing the importance of careful dose management. RECIST response assessment revealed that out of the 18 patients, 13 exhibited a partial response, while 3 had stable disease, and 2 showed disease progression. No complete responses were observed. The sum of diameters (SOD) based on RECIST 1.1 criteria demonstrated a significant reduction post-treatment, with a median decrease from 4.10 to 2.48 (p-value < 0.01).

Conclusion:

In conclusion, this study enhances our understanding of concurrent chemoradiotherapy's efficacy for LAGBC in a high-incidence region, emphasizing the need for ongoing exploration and tailored approaches with a greater number of patients.

Keywords: Gall Bladder, Chemoradiotherapy.

References:

1. Randi G, Franceschi S, La Vecchia C. Gallbladder cancer worldwide: Geographical distribution and risk factors. Int J Cancer. 2006 Apr 1;118(7):1591–602.

2. Sung H, Ferlay J, Siegel RL, Laversanne M, Soerjomataram I, Jemal A, et al. Global Cancer Statistics 2020: GLOBOCAN Estimates of Incidence and Mortality Worldwide for 36 Cancers in 185 Countries. CA Cancer J Clin. 2021;71(3):209–49.