Triple-hit lymphoma with hyperbasophilic Burkitt-like morphology and solely bone marrow/leukemic phase presentation

A 76-year-old woman was admitted because of progressive asthenia. There was no lymphadenopathy or organomegaly, which was confirmed by computed tomography scan. Laboratory studies included lactate dehydrogenase, 20 681 IU/L (normal range, 208-378). Hemoglobin was 113 g/L (normal range, 117-161), platelets 70.0 × 10⁹/L (normal range, 135-400) and white blood cell count was 42.5 × 10⁹/L (normal range, 4.0-10.5). A manual cell count revealed 35% immature cells (panel A; May-Grünwald-Giemsa stain, original magnification ×1000). The bone marrow aspirate showed 77% atypical immature cells with hyperbasophilic cytoplasm and conspicuous vacuolization (main panel; May-Grünwald-Giemsa stain, original magnification ×1000). Immunophenotype was CD19⁺, CD20⁺, CD22⁺, CD10⁺dim, and CD38⁺hi. TdT was negative. Karyotype was 48-52,XX+1, del(1)(p13),del81)(q21), add(3)(q27),+5,+8, add(8)(q24), +14,t(14;18)(q32;q21), +20, −22, +2mar[16]/46,XX[4] (panel B). Fluorescence in situ hybridization analysis showed rearrangements of c-MYC (62%), BCL2 (40%), and BCL6 (48%) (panels C, D, and E, respectively; original magnification ×1000). A diagnosis of triple hit high-grade B-cell lymphoma (HGBCL) (leukemic phase) was established.

Within the current World Health Organization classification, 2 HGBCL subgroups are described: those with MYC and BCL2 and/or BCL6 (HGBCL double-hit/triple-hit) and the other who lack those rearrangements (HGBCL not otherwise specified). Most HGBCL DL/TL present with widespread disease. Cases without nodal involvement are rare. One-half of HGBCL cases present with Burkitt-like morphology but with less basophilia and absence of vacuolization. We here present a rare case of triple-hit HGBCL with only bone marrow and peripheral blood involvement and hyperbasophilic Burkitt-like morphology that highlights the complexity of diagnosis with immature-appearing lymphomas.