“Double – hit (DH) lymphomas are a recently discovered subtype of lymphoma that is defined by a chromosomal breakpoint affecting the MYC/8q24 locus in combination with another recurrent breakpoint, for instance a t(14;18)(q32;q21), involving BCL2. In the 2008 WHO classification, they are classified as “B cell lymphoma unclassifiable with features intermediate between DLBCL and BL”.
In some ways it is similar to Burkitt’s; however, while the diagnosis of Burkitt lymphoma (BL) is generally straightforward, these lymphomas have have atypical morphologic and/or immunophenotypic features that overlap with other types of high-grade B-cell lymphoma, particularly diffuse large B-cell lymphoma (DLBCL). They often have an extremely poor prognosis, with a median survival of 6 or so months and represent an entity distinct from Burkitt’s Llymphoma and DLBCL.
Unfortunately, it is no known how to treat double-hit lymphomas. While it is tempting to consolidate with high dose therapy and transplantation, the entity is too new to have accumulated significant published information of response to therapy and role of transplantation. NCCN currently recommends for DLBCL: ”consider high dose therapy Category 2B for complete responders in high risk patients”. If there is not a complete response, it also lists this option.
ukema SM, Siebert R, Schuuring E, et al. Double-hit B-cell lymphomas. Blood 2011;117:2319-2331
Aggressive B-Cell Lymphomas: A Review of New and Old Entities in the WHO Classification ASH Education Book 2011 2011:506-514
The 2008 WHO classification of lymphoid neoplasms and beyond: evolving concepts and practical applications Blood 2011 117:5019-5032
Cuccuini W, Briere J, Mounier N, et al. MYC+ diffuse large B-cell lymphoma is not salvaged by classical R-ICE or R-DHAP followed by BEAM plus autologous stem cell transplantation. Blood 2012;119:4619-24.
Dunleavy K, Little RF, Pittaluga S, et al. A prospective study of dose-adjusted (DA) EPOCH with rituximab in adult with newly diagnosed Burkitt lymphoma: A regimen with high efficacy and low toxicity. Ann Oncol 2008;19:iv83-4.
Petrich AM, Gandhi M, Jovanovic B, et al. Impact of induction regimen and stem cell transplantation on outcomes in double-hit lymphoma: a multicenter retrospective analysis. Blood 2014;124:2354-61.
Stiff PJ, Unger JM, Cook JR, et al. Autologous transplantation as consolidation for aggressive non-Hodgkin’s lymphoma. N Engl J Med. 2013;369(18):1681-1690. -
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