Primary cerebral anaplastic large cell lymphoma containing abundant reactive histiocytes and eosinophils. A case report and literature review.

Primary cerebral anaplastic large cell lymphoma (ALCL) is very rare. We report on our experience with such a case and review the literature. A 46-year-old Taiwanese woman presented with headache, weakness of her right extremity, and limited eye movement. A solid mass (5 cm x 4 cm) at the left occipital lobe was almost completely removed. The neoplastic cells, some of which had reniform or embryo-like nuclei, were large and were admixed with abundant eosinophils, histiocytes, and some small lymphocytes. These neoplastic cells expressed CD30, CD43, granzyme B and T-cell intracellular antigen-1, but not ALK1, CD3, CD20, CD45, CD79a, cytokeratin, and EMA. They were positive for Epstein-Barr virus-encoded mRNA by in situ hybridization. Polymerase chain reaction study of formalin-fixed tissue showed a clonal gene arrangement of the T-cell receptor-gamma chain. ALCL of T-cell lineage with cytotoxic phenotype was diagnosed. The patient received cranial irradiation and has remained with no evidence of disease for 25 months of follow-up.