DIFFUSE LARGE B-CELL LYMPHOMAPRESENTED AS BONE LESIONS.A STUDY OF 21 CASES AND REVIEW OF THE LITERATURE

Diffuse large B-cell lymphoma is the most common lymphoma worldwide. Both morphologically and prognostically it represents a diverse
spectrum of disease. Non-Hodgkin lymphoma of bone comprises approximately 7% of malignant bone tumors, 5% of extranodal lymphomas, and
<1% of all non-Hodgkin lymphomas. Recent gene expression profiling studies have classified diffuse large B-cell lymphoma into 2 main subtypes,
germinal center B-cell and activated B-cell, with the germinal center type showing an overall better survival. Twenty one patients with diffuse
large B-cell lymphomas of bone were studied. The tumors were subclassified according to the criteria of the WHO standards and evaluated by
immunohistochemistry for expression of antigens associated with germinal center (GC) and non-GC stages of B-cell differentiation. The panel
included bcl-6, CD10, MUM-1, bcl-2, CD138. A survival analysis of 21 cases showed that GC-like tumors had longer overall survival duration
compared with non-GC-like tumors. This review focuses solely on de novo DLBCL presenting with bone involvement without evidence of extraskeletal
disease and do not include transformation from an underlying low-grade lymphoproliferative disorder.

I.V. Boulytcheva (1,2),M.D., PhD., C. Sciotto (2), M.D., PhD., Yu.N Soloviev (1), acad. of RAMS, N.E. Kushlinskii (1),corr. memb. of RAMS
1 -Federal State Budgetary Institution «The N.N. Blokhin Russian Cancer Research Center» of the Russian Academy of Medical Sciences, Moscow, Russian Federation;
2 -Penrose Hospital, Colorado, USA
E-mail: irena@boulytcheva.com