Philadelphia-positive T-cell acute lymphoblastic leukemia with polymyositis, migratory polyarthritis and hypercalcemia following a chronic myeloid leukemia.

Transformation of chronic myeloid leukemia (CML) often results in acute myeloblastic or, less frequently, in precursor B-cell acute lymphoblastic leukemia (ALL). T-cell blast crisis is rare. Hypercalcemia has also been described as a rare complication of CML, but this usually occurs as a terminal event. Here we report a case of a 35-year-old woman who developed a CD4(+)/CD8(+) T-cell ALL 2 years after the diagnosis of a typical Ph(+) CML. Polymyositis and polyarthritis preceded by 4 months, and symptomatic hypercalcemia occurred just before blastic transformation, probably representing paraneoplastic manifestations of the disease.