Two cases of hypergranular acute lymphoblastic leukemia.

Two patients with hypergranular acute lymphoblastic leukemia are presented: they represent 1.4% of patients with acute lymphoblastic leukemia studied and treated in a single institution in the past 12 years. This frequency is substantially lower than that reported in Caucasian populations. The blast cells of the patients disclosed an early-B phenotype, displaying CD45, CD10 and CD19 antigens. The cytoplasmic granules were positive for the PAS reaction. Both patients died early after starting treatment; a poor prognosis has been recorded previously for patients with this type of malignancy.