Outcomes of Patients with Limited-Stage Aggressive Large B-Cell Lymphoma with MYC Rearrangement with and without BCL2 and/or BCL6 Rearrangements: A Retrospective Analysis from 15 US Academic Centers

Introduction: Patients (pts) with limited stage (LS) aggressive large B-cell lymphoma (ALBCL) comprise 30-40% of ALBCLs and are usually treated with R-CHOP with or without consolidative involved field radiation therapy (IFRT). In pts with ALBCL, cytogenetic studies have identified a subset with high-risk disease who harbor MYC rearrangement (MYC-R) with or without BCL2 (BCL2-R) and/or BCL6 (BCL6-R) rearrangements. This has led to the adoption of intensive induction strategies in this population; however, it is unclear if such an approach is necessary in limited stage disease. Methods: We conducted a multi-center (15 US academic centers) retrospective study of MYC-R LS-ALBCL pts with diffuse large B-cell lymphoma (DLBCL) and high-grade B-cell lymphoma (HGBL) morphology. LS was defined by stage I and II confined to a single radiation field as determined by the treating center. Pts diagnosed between 1/1/2005 and 3/1/2017 were included. All pts received either R-CHOP or more intensive immuno-chemotherapy (IIC) (i.e. R-DA-EPOCH, R-hyperCVAD/MA, or R-CODOX-M/IVAC) with or without IFRT. Baseline demographic, clinical, laboratory, pathology and outcomes data was collected by retrospective chart review. Stage-modified IPI (sm-IPI) score was calculated [stage II (vs 1), age >60, elevated LDH, and ECOG performance status ≥ 2]. Differences in overall response rate (ORR), complete remission (CR) rate, 2-year progression-free survival (PFS) and overall survival (OS) were compared in pts treated with R-CHOP vs IIC and in pts treated with IFRT vs no IFRT. Results: A total of 142 pts with MYC-R LS-ALBCL were identified, of which 105 fulfilled the inclusion criteria. Baseline characteristics included: median age 65 yrs (range 21-85), 66% male; 14% stage I, 32% stage IE, 28% stage II, 26% stage IIE disease; 17% bulky, 58% extra-nodal, 15% transformed disease, 40% elevated LDH. The majority of pts (70%) had germinal center B-cell phenotype. Eighty-two pts had data on BCL2-R and BCL6-R, of which 41 (50%) had double-hit lymphoma (DHL), including 4 pts with triple-hit lymphoma. Forty-five pts (43%) received R-CHOP, of which 56% had IFRT. Sixty pts (57%) received IIC, of which 42% had IFRT. R-DA-EPOCH was the most common IIC regimen used (85%), followed by R-hyperCVAD/MA (12%). Age (p=0.38), stage (p=0.32), extra-nodal disease (p=0.84), LDH (p=0.09), sm-IPI (p=0.24), morphology (p=0.44) and double-hit status (p=1.00) were similar between pts receiving R-CHOP and IIC. Median no. o