title: Primary CNS anaplastic diffuse large B-cell lymphoma mimicking undifferentiated metastatic tumors: a case report.
abstract: Primary central nervous system lymphoma (PCNSL) is a rare intracranial tumor, with an annual incidence of six per million population. Anaplastic variant of primary CNS diffuse large B-cell lymphoma is less common; to our knowledge, there is only one other case report in the world literature. We describe a 71 year old immunocompetent female without significant past medical history who presented with confusion and a homogeneously enhancing midline mass. The patient underwent craniotomy for tumor biopsy, followed by high-dose methotrexate-based chemotherapy despite a remarkably low performance status. Histologically, this tumor was composed of undifferentiated polymorphic tumor cells, multi-nucleated giant cells, extensive necrosis, and conspicuous mitotic activity, mimicking undifferentiated metastatic tumors. Immunohistochemical stains demonstrated immunopositivity of tumor cells for CD20, MUM-1, and BCL-6, and negative staining for CD3, CD10, and CD30. The clinical course, diagnostic workup, pathologic correlates, and treatment outcomes are described.
authors.affiliation: Department of Pathology and Lab Medicine, North Shore University Hospital-Long Island Jewish Medical Center, 300 Community Drive, Manhasset, NY 11030, USA.
authors.forename: Tianyu
authors.initials: T
authors.lastname: Yang
authors.forename: Shawn
authors.initials: S
authors.lastname: Belverud
authors.forename: Albert Y
authors.initials: AY
authors.lastname: Yeh
authors.forename: Jela
authors.initials: J
authors.lastname: Bandovic
authors.forename: Peter
authors.initials: P
authors.lastname: Farmer
authors.forename: Rona F
authors.initials: RF
authors.lastname: Woldenberg
authors.forename: Alexis
authors.initials: A
authors.lastname: Demopoulos
authors.forename: Michael
authors.initials: M
authors.lastname: Schulder
authors.forename: Jian Yi
authors.initials: JY
authors.lastname: Li
mesh_terms: D000368:Aged; D016543:Central Nervous System Neoplasms / Q000175:diagnosis*; D005260:Female; D006801:Humans; D016403:Lymphoma, Large B-Cell, Diffuse / Q000175:diagnosis*; D008279:Magnetic Resonance Imaging / Q000379:methods