Mantle cell leukemia as a cause of leukostasis

Abstract

A 72-year-old man was admitted with hypoxemic respiratory distress. Given a white blood cell count of 600 × 10 9 /L and symptoms of leukostasis, emergency leukapheresis was initiated. The white blood cell count immediately after the first leukapheresis was paradoxically increased to over 700 × 10 9 /L. Peripheral blood smear findings showed morphologically immature mononuclear cells and numerous circulating mitotic figures. Initial flow cytometry results showed a lambda light chain-restricted B lymphoid population positive for CD20, CD19, CD5, and FMC-7, and negative for TdT, CD10, CD23, CD34, CD117, and myeloid markers, suggesting classification as a blastoid variant of mantle cell lymphoma in a leukemic phase. Subsequent testing using DNA fluorescence in situ hybridization was positive for t(11;14), confirming the diagnosis of mantle cell leukemia. Although mantle cell lymphoma occasionally transforms or can even present as leukemia (leukocytes .40 × 109/L), it is rare for it to present with such profound leukocytosis and an overwhelming number of pleomorphic/blastoid forms. Although morphology suggested acute lymphoblastic leukemia, a more specific diagnosis of blastoid variant mantle cell lymphoma was obtained in 12 hours by applying complementary techniques of flow cytometry and rapid cytogenetics.

Therapeutic leukocytapheresis for improvement in respiratory function in a woman with hyperleukocytosis and mantle cell lymphoma with a circulating small lymphocyte phenotype

“…In addition, the morphology of mantle cell lymphoma cells ranges from relatively mature phenotypes (small cells with notched or cleaved nuclei resembling follicular lymphoma or small cells with round nuclei resembling chronic lymphocytic leukemia) to more aggressive, immature, pleomorphic cell variants (blastoid or prolymphocytoid) . Three cases of leukocytapheresis treatment of leukostasis in leukemic mantle cell lymphoma, with variable results, have been reported in the English language literature (summarized in Table ) . All three were of the large cell variants.…”