Acute lymphoid leukemia following polycythemia vera

The tendency to evolve into acute leukemia is a well-known characteristic o f polycythemia vera (PV), which is shared with the remaining chronic myelop roliferative disorders and increases after the administration of cytotoxic agents. Acute transformation is usually of myeloid phenotype, whereas acute lymphoid leukemia (ALL) following PV is seldom observed. A 63-year-old wom an is described who developed ALL at 6 years from the initial diagnosis of PV, for which she had received radioactive phosphorus and hydroxyurea. The ALL was of B-cell type, corresponding to the L-3 subtype of the FAB classif ication. Despite the administration of combination chemotherapy the patient died shortly after the diagnosis of acute leukemia. The present case adds to seven previously described patients with the above association, all of w hom had received cytotoxic therapy for PV. Median interval from PV to ALL d iagnosis was 10 years, and there was a predominance of the B-cell phenotype . The prognosis was poor since all but one of the patients had a short surv ival after ALL diagnosis. The possible etiological and pathogenetic link be tween PV and the subsequent ALL is discussed.