Adult T-cell leukemia (ATL) with an unusual immunophenotype and a high cellular proliferation rate.

ABSTRACT

A patient with adult T-cell leukemia (ATL) characterized by a suppressor phenotype is reported. A 52-year-old mulatto male presented with symptoms and signs of hypercalcemia. His laboratory finding disclosed a peripheral blood specimen with abnormal cells characterized by a rather pleomorphic morphology and polylobated nucleous typical of ATL cells. Serum calcium and LDH were 18.2 mg/dl and 1373 IU, respectively. The phenotype of these cells was CD2+, CD4-, CD8+, CD28+ associated with the expression of activated antigens such as CD25, CD38, CD71 and CD30. Ki-67 positive were found in 20% of cells. The argyrophilic stain for nuclear organizer regions (AgNORs) was shown one cluster in 35% of abnormal cells. The serum antibodies were positive against human T-cell lymphotropic virus type I (HTLV-I) and clinical features were compatible with the diagnosis of ATL acute type. The combination therapy with cyclophosphamide, vincristine, prednisone decreased the number of leukemic cells but the clinical course was aggressive. He only responded transiently to treatment and died of multiorgan failure due to uncontrollable septicemia two weeks after admission.