Peripheral T-cell lymphoma presenting as myelofibrosis with the expression of basic fibroblast growth factor.

Myelofibrosis is often observed in chronic myeloproliferative disorders (CMPD), but non-Hodgkin's lymphoma with diffuse myelofibrosis is rare. We describe an elderly case with peripheral T-cell lymphoma-unspecified (PTCL) presenting as diffuse myelofibrosis. Bone marrow biopsy revealed infiltration of atypical lymphocytes and diffuse myelofibrosis without any increase in megakaryocytes. To discuss the pathogenesis of fibrosis, we examined cytokines relative to fibrosis using immunostaining. The expression of basic fibroblast growth factor (bFGF) was diffusely detected in the area of extracellular matrix of bone marrow. In addition, in situ hybridization revealed that infiltrating lymphoma cells expressed bFGF mRNA. Basic FGF, originally identified based on its mitogenicity for fibroblasts, has multiple potential, influencing neoangiogenesis, bone marrow fibrosis and the proliferation of tumor cells. Basic FGF might play an important role in the pathogenesis of myelofibrosis in the present case.