The outcome of high-grade B-cell lymphoma with MYC and BCL2 and/or BCL6 rearrangements or NOS compared to DLBCL patients from a single institution.

Abstract

7560 Background: 2016 update of the WHO 2008 classification of lymphoid neoplasms introduced new categories of highly aggressive B lymphomas (BCL): high grade B lymphoma (HGBL) with MYC and BCL2 and/or BCL6 rearrangements (HGBLR) and HGBL not otherwise specified (NOS). The prognosis for HGBL is generally considered poor, the optimal therapy is unknown. Here we evaluated outcome after first line treatment in patients with a diagnosis of HGBLR, HGBL, NOS, and DLBCL at our institution. Methods: Medical records of 591 consecutive patients with aggressive BCL were evaluated, archived pathology reports and samples were reviewed, diagnosis revised if necessary according to 2016 update of WHO classification. We identified 16 cases of HGBLR (3%), 26 cases of HGBL, NOS (4%), and 565 cases of DLBCL (93%). Response to first line therapy, progression free survival (PFS), and overall survival (OS) were calculated and compared between these three entities. Results: DLBCL patients were treated with RCHOP between 2005-2012, HGBL patients were treated between 2005-2016 with RDAEPOCH (n = 31, 5%), RCHOP or other regimens. For the first line treatment in patients with DLBCL, HGBLR and HGBL NOS, the overall response/complete response rate was 92%/75%, 81%/56%, 93%/65%, respectively (p = NS). After a median (range) follow up of 42(1-155) months, median PFS and OS for DLBCL was not reached. For both HGBLR and HGLB, NOS patients median PFS was 10 months, median OS was 16 months. The HR for risk of progression in patients with HGBLR vs DLBCL and HGBL NOS vs DLBCL was 2.4 (1.1-4.7), p = 0.01 and 2.0 (1.1-3.5), p = 0.01. The HR for risk of death, for HGBLR vs DLBCL and HGLB NOS vs DLBCL was 2.59(1.32-5.07), p < 0.01 and 1.8(0.9-3.3), p = 0.08. The risk of progression and the risk of death in HGBLR vs HGBL, NOS was similar, for PFS: 1.08 (0.46- 2.5), p = NS for OS: 1.2 (0.5 -3,1) p = NS. Conclusions: Our data confirms reports by others on poor prognosis for patients with a diagnosis of HGBL with MYC and BCL2 and/or BCL6 rearrangements as well as HGBL, NOS with an increased risk of death and risk of progression compared to DLBCL patients. There was no difference in outcome between HGBL-R and HGBL, NOS patients in our series.