ESTRO 2024 - Abstract Book

S1138

Clinical - Haematology

ESTRO 2024

lymph node segmentation, resulting in potentially smaller CTV to PTV margins. This study was supported by grant AuToMI (GR-2019-12370739, funded by the Italian Ministry of Health).

Keywords: TMI/TMLI, Whole-body magnetic resonance imaging

References:

(1) Jeffrey Y C Wong, Andrea R Filippi, Marta Scorsetti, et al. Total marrow and total lymphoid irradiation in bone marrow transplantation for acute leukaemia, The Lancet Oncology, 2020.

(2) Dei D, Lambri N, Stefanini S, et al. Internal Guidelines for Reducing Lymph Node Contour Variability in Total Marrow and Lymph Node Irradiation. Cancers, 2023.

904

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The efficacy of reduced-dose high-energy electron beam therapy in conjunctival MALT lymphoma

Jaeha Lee, Sang-wook Lee, Si Yeol Song, Young Seob Shin

Asan Medical Center, Radiation Oncology, Seoul, Korea, Republic of

Purpose/Objective:

This study aimed to assess clinical outcomes and treatment-related toxicities in patients with conjunctival mucosa associated lymphoid tissue (MALT) lymphoma treated with high-energy electron beams at radiation doses of 20 Gy or 30.6 Gy.

Material/Methods:

Sixty patients with biopsy-proven conjunctival MALT lymphoma, who underwent definitive radiotherapy at Asan Medical Center between June 2010 and May 2020, were retrospectively reviewed. Treatment involved either 20 Gy (2 Gy per fraction) or 30.6 Gy (1.8 Gy per fraction) of high-energy electron irradiation, with routine lens shielding. Clinical response was categorized into complete response (CR) and non-CR based on physical examination. The primary endpoint was the local recurrence rate, with secondary analyses of clinical response rate, factors influencing clinical outcomes, and treatment-related toxicity.

Results:

Among the 45 cases included, the median follow-up was 67 months, and the median age at diagnosis was 48 years. Notably, the group treated with 20 Gy demonstrated a high local control rate, with a complete response (CR) rate of