ESTRO 2022 - Abstract Book

S258

Abstract book

ESTRO 2022

OC-0296 The role of radiation therapy in the treatment of primary hepatic lymphomas

J. Ma 1 , R. Daou 2 , J. Bou Eid 2 , J. Lee 1 , B. Fregonese 1 , J. El-Khoury 2 , N.A. Wijetunga 1 , H. Hubbeling 1 , K. Tringale 1 , E. Lebow 1 , B. Imber 1 , J. Yahalom 1 , C. Hajj 1 1 Memorial Sloan Kettering Cancer Center, Radiation Oncology, New York, USA; 2 Saint Joseph University of Beirut, Family Medicine, Beirut, Lebanon Purpose or Objective Primary hepatic lymphomas (PHL) are an extremely rare form of non-Hodgkin Lymphoma (NHL) for which there are no established treatment guidelines, with available literature largely comprised of small case reports. Therefore, we evaluate our institutional experience treating PHL within the context of existing literature to better understand treatment modalities, role of radiotherapy (RT), and outcomes. Materials and Methods We conducted a single institutional retrospective analysis of all PHL patients (pts) diagnosed from 2000-2021 with a biopsy- proven liver lesion without other lymphomatous solid organ involvement, except for concurrently diagnosed splenic lymphomas. Subgroup analysis was performed for diffuse large B-cell lymphoma (DLBCL) and indolent lymphomas, which included marginal zone (MZL), follicular (FL), and low-grade B-cell lymphoma (BCL), NOS. Univariable (UVA) and multivariable analysis (MVA) for overall survival (OS) was performed using the Cox proportional hazards model. A literature review was conducted using key words “liver”, “lymphoma”, and “treatment.” Results We identified 30 PHL pts within the institutional cohort and 192 pts from comprehensive literature review (Table 1). DLBCL subgroup analysis (n=15) with UVA for OS is listed in Table 2. On MVA for OS, only ECOG score (p=0.02) and Lugano stage (p=0.04) remained significant. Indolent lymphoma subgroup analysis (n=9) with UVA for OS is listed in Table 2 and Figure 1. On MVA for OS, only age remained significant.

Table 1. Patient characteristics for institutional and literature review cohorts.