Primary Leptomeningeal Lymphoma: Clinicopathologic Features of 2 Rare Phenotypes

M. Adelita Vizcaino, Caterina Giannini, Rebecca L. King, Derek R. Johnson, Tong Yang, Aditya Raghunathan

Research output: Contribution to journalArticlepeer-review


Primary leptomeningeal lymphoma is exceedingly rare. We describe 2 rare lymphoma cases with exclusive leptomeningeal disease: 1 ALK-positive (ALK+) anaplastic large cell lymphoma (ALCL) and 1 primary effusion lymphoma (PEL). Case 1: A 19-year-old man presented with symptoms concerning for leptomeningitis. Cerebrospinal fluid (CSF) analysis revealed lymphocytic pleocytosis. Spine MRI demonstrated pial enhancement from T10 through the conus medullaris and cauda equina enhancement/thickening. A biopsy showed leptomeningeal involvement by large lymphoma cells with hallmark cells and brisk mitotic activity. By immunohistochemistry, cells were CD7/CD30-positive with cytoplasmic ALK staining. No systemic disease was identified. The diagnosis of primary leptomeningeal ALK+ ALCL was made. Despite 2 CSF relapses requiring systemic therapy and autologous bone marrow transplant, the patient was in complete clinical remission 9 years after the diagnosis. Case 2: A 60-year-old, human immunodeficiency virus-positive man presented with symptoms suggestive of leptomeningitis. Brain MRIs revealed multifocal, supratentorial, and infratentorial leptomeningeal enhancement. A right frontal biopsy demonstrated leptomeningeal involvement by large lymphoma cells negative for B-cell immunostains, but CD138, MUM-1, and HHV8-positive, with aberrant CD3 expression. EBV-encoded RNA in situ hybridization was positive. In absence of solid lesions/extracranial involvement, the diagnosis of leptomeningeal PEL was rendered. Despite initial complete remission after chemotherapy, the patient died 9 months later.

Original languageEnglish (US)
Pages (from-to)1002-1007
Number of pages6
JournalJournal of Neuropathology and Experimental Neurology
Issue number12
StatePublished - Dec 1 2022


  • ALK-positive anaplastic large cell lymphoma
  • Central nervous system lymphoma
  • Immune-privileged sites
  • Immunodeficiency
  • Leptomeninges
  • Primary effusion lymphoma

ASJC Scopus subject areas

  • General Medicine


Dive into the research topics of 'Primary Leptomeningeal Lymphoma: Clinicopathologic Features of 2 Rare Phenotypes'. Together they form a unique fingerprint.

Cite this