RESUMO
<p><b>OBJECTIVE</b>To study the clinicopathologic features, prognostic indicators and possible etiology of primary non-Hodgkin lymphoma of bone (PNHLB).</p><p><b>METHODS</b>The clinicopathologic features of 17 cases of PNHLB were reviewed. In-situ hybridization for Epstein-Barr virus early RNA (EBER) and polymerase chain reaction for bcl-2/JH gene rearrangement were performed using paraffin-embedded materials. The correlation between serum lactic dehydrogenase level, treatment options, international prognostic indicator (IPI) and immunophenotype with clinical outcome were analyzed.</p><p><b>RESULTS</b>The majority of the 17 cases studied was diffuse large B-cell lymphoma (94.1%). The 5-year survival rate was 68.8%. Unfavorable prognostic factors included high-risk IPI (P = 0.031) and bcl-2 overexpression (P = 0.028). Treatment options and expression of CD10, MUM-1 or bcl-6 did not correlate with clinical outcome (P > 0.05). Only 1 patient was positive for EBER, as demonstrated by in-situ hybridization.</p><p><b>CONCLUSIONS</b>The clinical outcome of PNHLB is relatively favorable. IPI and bcl-2 expression may serve as useful prognostic indicators. EBV is likely not related to pathogenesis of this type of lymphoma.</p>