A case of adult T-cell leukemia/lymphoma (ATLL) with atypical morphology and immunophenotypic profile

A 23-year-old female patient presented with abdominal lymphadenopathy, severe hypercalcemia, leukocytosis (54.9x10⁹/L), mild anemia, and normal platelet count. Peripheral blood smear showed 40% atypical lymphoid cells with convoluted nuclei (Figure 1). Flow cytometry analysis performed in the peripheral blood revealed an abnormal population of memory CD4+ T cells (CD5+/-, CD3+/-, CD7-, CD45RO-, CD25-), compatible with Sézary cells. However, serology for human T-cell lymphotropic virus type 1 (HTLV-1) was positive, the diagnosis of CD25-negative ATLL being established.
 

ATLL is a rare peripheral T-cell lymphoma that occurs in about 5% of HTLV-1 carriers from endemic regions, after a long latency period⁽¹⁾. Four clinical subtypes of ATLL with different clinical courses are described: smoldering, chronic, acute leukemic, and lymphomatous⁽¹⁾. Morphologically, typical ATL cells display polylobulated nuclei, being recognized on smears as “flower cells”⁽²⁾. ATLL neoplastic lymphocytes originate in CD4+ helper T cells that share the CD25+ phenotype with regulatory T cells⁽³⁾. Nevertheless, a lack of CD25 expression was reported in a subset of ATLL cases⁽⁴⁾.

We report atypical morphological features of lymphoid cells (“Burkitt-like”) in our patient, as well as an unusual immunophenotypic profile.

Autori pentru corespondenţă: Cristina Mambet E-mail: cristina.mambet@gmail.com

CONFLICT OF INTEREST: none declared.

FINANCIAL SUPPORT: none declared.

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