Outcome of Patients > Age 40 with Burkitt Lymphoma (BL) Treated with Aggressive Chemotherapuetic Regimens: Results from the International Burkitt Lymphoma Collaborative Group.

BL is considered a highly curable tumor when treated with dose-intensive, multiagent chemotherapy including central nervous system prophylaxis. 60–90% of pediatric and young adult patients (pts) with BL achieve durable remission if treated appropriately. However, the outcome of older adults with BL is more uncertain. We first investigated the SEER database and determined that 57% of reported pts with BL are > age 40. We then performed a systematic review of published manuscripts describing outcome of adult pts (> age 15) with confirmed de novo BL (REAL/WHO defined and confirmed) treated in the modern therapeutic era. Of 33 manuscripts, 17 were excluded due to small sample size (< 10 pts), inclusion of pts with HIV, inclusion of pts with alternate histologies, or utilization of CHOP-like therapy. Corresponding authors of the remaining 16 manuscripts were contacted to provide details on outcome of pts > age 40 for inclusion in a database, and full data is available from 12 manuscripts (10 prospective; 2 retrospective). 470 total adult BL pts ages 15–79 were treated, and 183 (39%) were > age 40. Pts > age 40 had significantly inferior outcomes in 10 of the 12 series. Treatment regimens included intensive short duration therapy (4 series; total N=212; > 40 N=93); ALL-like therapy (6 series; total N=182; > 40 N=62) and ASCT as part of induction therapy (2 series, total N=76; > 40 N=28). The median overall survival at 2 years (OS) for all pts treated with short duration therapy was 71%, and for pts > age 40 was 39%. The OS for all pts treated with ALL-like therapy was 51%, and for pts > age 40 was 40%. Pts > age 40 treated with ASCT as part of induction regimens had somewhat better outcomes (median OS 62%), however this represents a small number of pts who may have been subject to more rigorous selection criteria. We conclude that pts > age 40 with BL are significantly underrepresented in the published clinical trials. Even when these pts are treated with appropriate intensive chemotherapy, the OS is inferior compared to published outcomes in younger pts, and is similar to OS survival historically observed with CHOP chemotherapy alone (40%). Future efforts should evaluate whether BL in older adults has unique biological features. Novel therapeutic regimens, with decreased toxicity, targeting the older majority pts with BL are required.