[Peripheral T-cell lymphoma initially presenting as secondary myelofibrosis]

A case of peripheral T-cell lymphoma presenting with secondary myelofibrosis and meningeal involvement is described. A 65-year-old female was admitted because of remarkable weight loss and pancytopenia. On admission, she was confused and showed tiny cervical lymph nodes but no hepatosplenomegaly. Bone marrow aspiration resulted in dry tap and its biopsy showed remarkable myelofibrosis with marked decrease of hematopoiesis and increase of lymphoid cells. Lymph node biopsy revealed diffuse medium sized cell lymphoma, which was diagnosed as CD3+4+8-peripheral T-cell lymphoma with immunohistochemistry (anti-HTLV-1 antibody negative). The lymphoid cells of bone marrow expressed the markers of T-cell lineage (LCA+ UCHL1+ MT1+ L26- MB1-). The cerebrospinal fluid examination revealed many lymphoma cells. She was treated with CHOP regimen and intrathecal injection of MTX. After three months, bone marrow biopsy showed recovery of hematopoiesis and disappearance of lymphoma cells and reticulin fibers. Immunohistochemical analysis of bone marrow specimen was useful for the diagnosis of atypical myelofibrosis.