Development of chronic lymphocytic leukaemia in a patient with polycythaemia vera.

A 73-year-old patient who had polycythaemia vera (PV), and who 6 years later developed chronic lymphocytic leukaemia (CCL) is described. 2 years after the appearance of CLL, the polycythaemic phase showed a remission following treatment with phlebotomy and busulfan. CLL did not make all the characteristics of PV disappear: leucocyte alkaline phosphatase and fibrosis of the bone marrow remained increased and the erythrocyte sedimentation rate remained low. The abnormal lymphocytes were B-cells and had the peculiarity that most of their nuclei showed a deep cleft, and some were bilobed. Chromosomal studies of the bone marrow showed the presence of a metacentric chromosome in the C-group, while the karyotype of the peripheral blood was normal. This case is described because of the rarity of the coexistence of these 2 diseases in the same patient.