Coexistent chronic lymphocytic leukemia and polycythemia vera requiring no treatment.

Simultaneous presentation of chronic lymphocytic leukemia and polycythemia vera is reported in a previously untreated patient. The course was remarkably mild with almost no treatment, suggesting control of each disease by the other. The association of polycythemia vera (PV) and lymphoid neoplasms in the same patient is very unusual in the absence of previous cytotoxic therapy. Six cases of PV and chronic lymphocytic leukemia (CLL) have been reported, in which the occurrence of the two disorders was simultaneous, or sequential but spontaneous. We describe an additional patient in whom the presence of the two malignancies was clearly established, and who needed almost no therapy for more than 3 yr.