Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0032463 (polycythemia vera)
 3,374 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Forty-eight patients with polycythemia vera (PV) were retrospectively studied for incidence of acute leukemia over a 12 year period. Initial clinical features, hemogram, RBC mass, B12 levels, neutrophil alkaline phosphatase (NAP), and therapy given were studied for association with development of acute leukemia. There were 25 males and mean age at diagnosis was 61.4 years. Initial Hg was 18.38 +/- 1.86 g/dl, WBC 16.44 +/- 12.92 (x 1,000/mm3), platelets 632.94 +/- 303.81 (x 1,000/mm3), B12 1,030.93 +/- 445.20 pg/ml, and neutrophil alkaline phosphatase (NAP) score 136.63 +/- 55.14. Twenty-three patients were treated with phlebotomy alone and 25 received additional myelosuppressive therapy as follows--2 received p32 alone, 4 alkylating agents alone, 8 hydroxyurea (HU) alone, and 11 received 2 or more (multiple) of these agents. None of those treated with phlebotomy alone but 6 of 25 (24%) patients given myelosuppressive therapy developed acute leukemia (P = .03) after a mean period of 46.8 months from start of myelosuppressive therapy. Four of the 11 patients (36%) receiving multiple agent therapy developed acute leukemia (P = .019). Initial hemoglobin levels, but not the other clinical parameters, were significantly higher in patients who developed acute leukemia (P = .002), and this difference persisted in various subgroups receiving myelosuppressive therapy. Thus, high initial hemoglobin and use of any myelosuppressive therapy are associated with an increased risk of leukemic transformation in polycythemia vera. This risk becomes substantial with the use of two or more myelosuppressive agents. Since myelosuppressive therapy does not prolong survival, its role in the management of polycythemia vera should be reexamined.
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PMID:Leukemic transformation in polycythemia vera: analysis of risk factors. 232 2

In polycythemia vera (PV), treatment with chlorambucil and radioactive phosphorus (p32) increases the risk of leukemic transformation from 1% to 13-14%. This risk has been estimated to be 1-5.9% with hydroxyurea (HU) therapy. When compared with historical controls, the risk with use of HU does not appear to be statistically significant. The leukemogenic risk of HU therapy in essential thrombocytosis (ET) and in myelofibrosis with myeloid metaplasia (MMM) is unknown. HU remains the main myelotoxic agent in the treatment of PV, ET, and MMM. We studied 64 patients with these three disorders, seen at our institution during 1993-1995. The patients were studied for their clinical characteristics at diagnosis, therapies received, and development of myelodysplasia or acute leukemia (MDS/AL). Forty-two had PV, 15 ET, and 6 MMM, and 1 had an unclassified myeloproliferative disorder. Of the 42 patients with PV, 18 were treated with phlebotomy alone, 16 with HU alone, 2 with p32, 2 with multiple myelotoxic agents, and 2 with interferon-alpha (IFN-alpha). Two patients from the phlebotomy-treated group, one from the HU-treated group, and 1 from the multiple myelotoxic agent-treated group developed MDS/AL. In the larger group, 11 received no treatment or aspirin alone, 18 were treated with phlebotomy alone, 25 with HU, 5 with multiple myelotoxic agents, 2 with p32, 2 with IFN-alpha, and 1 with melphalan. Study of the entire group of 64 patients showed that only one additional patient (total of 5 out of 64) developed MDS/AL. This patient had been treated with HU alone. Statistical analysis did not show any association between clinical characteristics at diagnosis, or HU therapy, and development of MDS/AL (P=0.5). Thus, our data provide no evidence suggestive of increased risk of transformation to MDS/AL with HU therapy in PV, ET, and MMM. Larger, prospective studies are needed to study this issue further.
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PMID:Leukemogenic risk of hydroxyurea therapy in polycythemia vera, essential thrombocythemia, and myeloid metaplasia with myelofibrosis. 863 10