Autologous Stem Cell Transplantation For Adult Burkitt Lymphoma In The Rituximab Era: A Retrospective Study Of The Lymphoma Working Party (LWP) Of The European Group For Blood and Marrow Transplantation (EBMT)

The role of autologous stem cell transplantation (ASCT) for Burkitt Lymphoma (BL) in adults in the era of modern intensive chemotherapeutic regimes remains to be defined. The addition of Rituximab has been shown to improve outcomes in patients with BL, but how this influences outcomes for patients receiving ASCT is not clear. Prior studies of ASCT in BL have often included large number of patients treated with outmoded CHOP-like regimes, have often included children, and have combined outcomes of BL and Burkitt-like lymphoma (BLL).

We conducted a retrospective registry based analysis of adult patients who were reported to the EBMT as having a diagnosis of BL and who had received an ASCT in the period of 2000-2011. Treatment history and histology reports were collected as part of the study.

Data including histology reports were returned for 125 patients who received a first ASCT between 2000 and 2011. Median age was 38.5y (range 16-64); 89 patients (71%) were male. While the diagnosis by pathology report was considered to be classic BL in 97 (78%) cases, the diagnostic possibility of BLL or atypical BL was considered in 28 (22%) cases. Twenty-one patients (17%) had stage I/II and 99 (80.5%) had stage III/IV disease. Fifty-one patients (53.7%) received Rituximab as part of 1st line treatment. Of all patients, 90 (74%), and 31 (25%) patients received ASCT in CR1/ VGPR1/PR1, and >CR1/ advanced disease (AD), respectively.

5 year estimates for overall survival (OS) for the CR1 and VGPR1/PR groups were 80% and 71% respectively (p=0.23). Factor that was significant for OS in multivariate analysis (MVA) by Cox modeling, for the CR1/VGPR1/PR1 group was age <39 vs >39 (HR = 6.21 ; 95%CI 2.03-19 ; p=0.0013); status at transplant, i.e., PR1/VGPR1 vs CR1 (HR = 2.25 ; 95%CI 0.90-5.61) approached significance (p=0.081). Age >39 was the only significant risk factor for disease fee survival (DFS) in this group (HR = 3.11 ; 95%CI 1.27-7.6 ;p=0.0131). CNS involvement was a significant risk factor for relapse (HR 3.58, 95%CI 1.27-11.62, p= 0.017). Of note, administration of Rituximab as part of 1^stline therapy did not appear to impact on OS or DFS. For patients receiving ASCT in CR>1 and AD, the OS was 59% and 25% respectively (p=0.042). Achievement of a subsequent CR had a significant impact on OS (HR 2.84, 95%CI 1.03-7.79, p=0.042) and DFS (HR 2.64, 95%CI 0.97-7.17, p=0.056). There was a trend for improved DFS for the BL vs the BLL patients that approached statistical significance (p=0.059).

In this analysis of 125 adult patients with BL and BLL who received an ASCT in the era of intensive chemoimmunotherapy, disease status at transplant was the main determinant of outcome; age influenced OS and DFS for patients autografted in CR1/PR1/VGPR1. Prior Rituximab therapy did not predict post ASCT outcomes. Patients in PR1/ VGPR1 at the time of ASCT had outcomes that were not significantly inferior to those transplanted in CR1, and the former group of patients represent a subset who are most likely to derive a benefit from proceeding to an upfront ASCT. For those patients who have a chemosensitive relapse, ASCT offers the probability of salvaging a significant proportion. Patients with AD and chemoresistant disease had poor outcomes, and in such patients modalities of treatment other than ASCT should be pursued.

Sureda:Novartis: Consultancy, Membership on an entity’s Board of Directors or advisory committees. Afanasyev:Alexion: Honoraria. Dreger:Riemser Pharma: Consultancy, Honoraria, Research Funding.