eMedicine Specialties > Pediatrics: General Medicine > Hematology

Polycythemia Vera: Treatment & Medication

Author: Josef T Prchal, MD, FRCP, Professor of Medicine (Hematology), Adjunct Professor of Pathology and Genetics, University of Utah School of Medicine
Coauthor(s): Scott J Samuelson, MD, Fellow in Hematology and Oncology, Huntsman Cancer Institute, University of Utah School of Medicine
Contributor Information and Disclosures

Updated: Sep 3, 2009

Treatment

Medical Care

Treatment of polycythemia vera (PV) depends on whether the disease is in the plethoric phase or the spent phase.

  • In the plethoric phase, the goal of treatment is controlling thrombotic episodes by restraining monoclonal proliferation rather than restoring polyclonal growth and maturation of cells. Interferon alfa is an exception; a few case reports have reported restoration of polyclonality.
  • In the plethoric phase, polycythemia vera is treated first by performing phlebotomy until the hematocrit is under reasonable control. Most patients can tolerate removal of 450-500 mL of blood every 2-4 days. As more blood is removed and the patient becomes iron deficient, the hematocrit becomes easier to control, and the phlebotomy schedule should be adjusted accordingly. Although phlebotomy is effective for controlling erythrocytosis, it does not affect the variable leukocytosis, thrombocytosis, or thromboembolic events found in polycythemia vera.
  • For many years, the mainstay of therapy of polycythemia vera has been phlebotomy with a goal hematocrit level of less than 45% in men and less than 42% in women. This recommendation is based on retrospective data that are now almost 30 years old and, the authors believe, potentially inaccurate. Recently, DiNisio and colleagues published data in patients with polycythemia vera that suggested that differences in hematocrit in the range of 40-55% were not associated with the risk of thrombosis nor with mortality.13
  • Landolfi et al performed an extensive retrospective review of 1638 PV patients studied as part of the European collaboration study on low-dose aspirin in polycythemia (ECLAP).14  
    • In this trial, no correlation was observed between hematocrit and risk of thrombosis. 
    • Limitations of this study include its retrospective nature and relatively short follow-up (2.8 y median). Therefore, the authors of this eMedicine article believe that the true hematocrit goal in polycythemia vera is not clear (if it is present at all). This issue remains to be sorted out in prospective fashion. Although phlebotomy is still recommended by many experts, it is clearly a controversial issue.
    • In most patients, low-dose aspirin is started to reduce the risk of thromboembolic events, and phlebotomy is continued as necessary to control the hematocrit. This recommendation is based on results of the ECLAP study, in which patients with polycythemia vera and no clear indications for aspirin were randomly assigned to receive aspirin 100 mg/d or no aspirin.14
    • The study showed a minor but statistically significant decreased risk of cardiovascular death, nonfatal myocardial infarction, nonfatal stroke, pulmonary embolism, and major venous thrombosis with aspirin therapy. Also, low-dose aspirin did not significantly increase rates of hemorrhage.
    • The retrospective review of the ECLAP data confirmed older age and previous thrombosis as risk factors for thrombotic events.
    • Although no correlation was demonstrated between thrombosis risk and hematocrit, what was shown was that a WBC count of more than 15,000/μL, when compared with a WBC <10,000/μL, was an independent risk factor for major thrombosis, primary manifested as an increased risk of myocardial infarction.
    • Risk stratification is important in deciding whether or not chemotherapeutic cytoreductive therapy is indicated.
    • Most agree that high risk for thrombosis is present when the patient is older than 70 years and/or has a previous history of thrombosis. Note that the age is different than in risk stratification of essential thrombocythemia.
  • A platelet count of more than 1.5 million/μL is a risk factor for bleeding and is frequently considered a high risk indication favoring chemotherapeutic cytoreduction. Uncontrolled traditional cardiac risk factors, especially smoking, are considered by most to place a patient in a high-risk category. However, when these factors are well controlled, therapy for high risk may not be justified. Whether an additional agent should be given depends on the patient's thrombotic risk. The decision is a tradeoff between a reduction in thrombotic events and an increased incidence of malignancy. The initial Polycythemia Vera Study Group (PVSG) investigators compared phlebotomy, phlebotomy with32 P, and phlebotomy with chlorambucil. Median survival was 13 years, 11 years, and 9 years, respectively. The incidence of thrombosis was 23% in the phlebotomy-only group versus 16% in the32 P-and-phlebotomy group.
  • The rate of acute myeloid leukemia was 1.5%, 10%, and 13% for phlebotomy, phlebotomy with32 P, and phlebotomy with chlorambucil, respectively. Because of the increased rate of acute myeloid leukemia in polycythemia vera treated with chlorambucil, this drug is no longer used for myelosuppression. Rates of GI and skin cancers also increased 4%, 9%, and 12% when patients were treated with phlebotomy, phlebotomy with32 P, and phlebotomy with chlorambucil, respectively. Clearly, myelosuppression reduces the incidence of thrombotic events but increases the risk of malignancy.
  • Because of these results, a phase II efficacy trial was performed by using hydroxyurea instead of chlorambucil or32 P to see if a less leukemogenic agent could control thrombosis. In that trial, 51 patients with polycythemia vera were given hydroxyurea 30 mg/kg/day for 1 week then 15 mg/kg/day with the goal to maintain a platelet count of <600,000/cm3 and a hematocrit of <50% with minimal phlebotomy. The incidence of thrombosis in the first 2 years of treatment (when most thromboses occur) was 9%, significantly lower than the historical control of 23% for phlebotomy alone in the PVSG trial. At a median follow up of 8.6 years, the incidence for acute myeloid leukemia was 6% for hydroxyurea compared with 1.5% for phlebotomy only. At the time of analysis, this difference was not statistically significant but the later addition of 2 cases of myelodysplasia in the hydroxyurea arm increased the incidence to a significant 8%.
  • Because of the theoretically possible leukemogenic risk of hydroxyurea, anagrelide has been used to control increased platelet counts with the aim to reduce thrombotic events. In the PT1 trial in the United Kingdom, patients with essential thrombocythemia were randomly assigned to receive hydroxyurea or anagrelide. The study demonstrated an increased risk of thrombosis with anagrelide. The implication for polycythemia vera is unclear, but a reduction in platelet count does not affect rate of thrombosis in essential thrombocytopenia; a similar result is expected in polycythemia vera.
  • Interferon has been used for myeloproliferative diseases with efficacy in the past, but toxicity/tolerance has always limited its use in patients. However, in a recent phase II study by Kiladjian et al, pegylated interferon alfa-2a (Pegasys) was administered to 40 patients with polycythemia vera (median follow-up, 31.4 mo).15  A completed hematologic response was achieved in 94.6%, with 7 patients achieving complete molecular response of the JAK2V617F that was durable. Most patients tolerated interferon well, and no vascular events were recorded. The acceptable tolerability, efficacy and extremely low leukemogenic risk may make interferon alfa first line therapy in the future. 
  • The authors recommendations are as follows:
    • Based on the above data, in the authors' clinical practice, chemotherapeutic cytoreductive therapy is used in all patients who are high risk. Generally, the drug of choice is hydroxyurea. The authors attempt to titrate the drug to achieve normalization of the WBC count. This is based on the data stated above. The authors are honest with patients that this treatment is based on retrospective data that still need to be prospectively proven. The authors also monitor the hematocrit level, and although phlebotomy is performed for symptoms or very high values, the authors do not feel that fully achieving a goal of 45% in men and 42% in women is required.
    • Patients who are low risk generally do not require chemotherapeutic cytoreductive therapy. However, the concern of increased risk of thrombosis (primarily myocardial infarction) due to leukocytosis brings into question whether or not low-risk patients with a WBC count of more than 15,000/uL should receive cytoreductive therapy. This question remains to be addressed in a prospective fashion; currently, cytoreductive therapy in this situation cannot be firmly recommended.
    • As stated above, the authors believe that current recommendations to phlebotomize to a goal hematocrit of 45% in men and 42% in women may be inaccurate. Clearly, patients with symptomatic hyperviscosity should receive phlebotomy sufficient to relieve their symptoms. The authors also consider phlebotomy in patients with a very high hematocrit (>55%), but do not feel bound by current guidelines, based on the above data.
    • All patients receive low dose aspirin, usually 81 mg, unless a contraindication is noted.
    • As more clinical data is collected on pegylated interferon alfa-2a (Pegasys), some recommend its use as a potential first-line agent for cytoreduction; however, a planned randomized prospective study of Pegasys versus Hydrea should resolve the issue of optimal first-line polycythemia vera therapy.
    • Occasionally special treatment situations arise.
    • P32 is a reasonable option in the patient who is unreliable or who has a limited lifespan because of the convenience of one injection resulting in long term control. The principle drawback is the increased risk of malignancy.
    • In pregnant women, interferon can be used to treat polycythemia vera. The mechanism is unclear, the side effects are moderate and often severe, and the drug is expensive. However, it is not teratogenic, it can reasonably control symptoms, and there are rare case reports of restoration of polyclonality. Interferon is also a reasonable consideration in a young patient because of possible concerns of leukemogenicity of hydroxyurea. Recent data suggest that pegylated interferon-alpha-2a (Pegasys) is likely to be equally (and possibly more) effective. It is dosed once weekly which likely improves compliance. Some suggest that it may also be better tolerated than standard interferon.
    • Erythromelalgia responds to low dose aspirin or reduction of the platelet count to normal with low dose myelosuppressive agents.
    • Pruritus can be disabling and life altering in polycythemia vera. High water temperatures vigorous skin rubbing are factors in inciting itching. Taking cooler baths and patting the skin dry can provide some symptomatic relief. Also, starch baths (half a box of Linet starch in a tub of water) can be effective. Pharmacologic treatment options include antihistamines (eg, cyproheptadine at 4 mg orally 3 times daily), histamine 2 (H2) receptor blockers (eg, cimetidine at 300 mg orally 4 times daily), photochemistry, danazol, and interferon alpha. Serotonin reuptake inhibitors (eg, paroxetine at 20 mg orally daily or fluoxetine at 10 mg orally daily) can also be used. In severe refractory cases, myelosuppression may be required.
    • Patients with symptomatic hyperuricemia (gout, urate kidney stones) receive allopurinol. The authors also obtain uric acid levels and treat asymptomatic hyperuricemia if the level is significantly elevated.

Surgical Care

  • Polycythemia vera is not treated surgically, except in the spent phase when splenectomy may be performed to relieve symptoms related to mass effect and pancytopenia.
  • Patients undergoing surgery have a very high risk of postoperative thrombosis.

Consultations

  • All patients suspected of having polycythemia vera should be referred to a hematologist.

Diet

  • Beer with cobalt foam stabilizers should be eschewed. Otherwise, a normal healthy diet is recommended.

Activity

  • Patients with polycythemia vera can have a normal active life.

Medication

Biologic response modifiers

Biologic response modifiers elicit antiproliferative, antiviral, and immunomodulating effects. They inhibit cellular growth and alter cellular differentiation.


Interferon alfa-2a, recombinant (Pegasys)

Protein produced in response to viral infection and other inflammatory stimuli. The exact mechanism is unknown, but it is believed to exert an antiproliferative effect. Produced by recombinant DNA techniques in E coli. Controls erythrocytosis and reduces spleen size. Unlike hydroxyurea or anagrelide, can also ameliorate the intractable pruritus often found in polycythemia vera. Sporadic case reports have noted cytogenetic remissions, suggesting a possible biologic effect.

Adult

90 mcg SC qwk for 2 wk, then titrate upward q2wk to target dose of 135 μ g/wk; if no hematologic response, may further increase to 180 μ g/wk

Pediatric

Not established

Weak CYP1A2 inhibitor; may increase adverse effects of ACE inhibitors (especially granulocytopenia) and warfarin's anticoagulant effects; agranulocytosis has been reported when coadministered with clozapine; theophylline, zidovudine, and vinblastine may increase toxicity of INF-alfa; corticosteroids may decrease INF-alfa therapeutic effects; coadministration with interleukin-2 may increase risk of renal failure; may decrease melphalan serum concentrations; may decrease hematopoietic effects of erythropoietin

Documented hypersensitivity; history of severe mental depression (relative contraindication); decompensated liver disease, autoimmune hepatitis, history of autoimmune disease, and rapidly progressing or life threatening visceral AIDS-related Kaposi's sarcoma

Pregnancy

C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus

Precautions

Caution with liver or kidney dysfunction, brain metastases, seizure disorder, multiple sclerosis, compromised CNS, or history of mental depression or suicidality; common adverse effects include fever, malaise, nausea, peripheral neuropathy, and vomiting

Antiplatelet agents

These agents prevent formation of thrombi-associated polycythemia.


Aspirin (Anacin, Ascriptin, Bayer)

Irreversibly acetylates platelet cyclooxygenase, resulting in a decrease in thromboxane A2, the prostaglandin responsible for platelet shape change, granule release, and aggregation. Prescribed for most patients with polycythemia vera.

Adult

81 mg PO qd; higher doses have not been shown to decrease rates of thrombosis and have been associated with higher rates of hemorrhage

Pediatric

Not established

Minor CYP2C8/9 substrate; when given with heparin, low molecular weight heparins, NSAIDS, platelet inhibitors, warfarin, and other oral anticoagulants, there may be an increased risk of bleeding; increase bleeding may occur when coadministered with herbal supplements (eg, Cat's claw, dong quai, evening primrose, feverfew, garlic, ginger, ginkgo, red clover, horse chestnut, green tea, ginseng); certain foods contain salicylate and may result in salicylate accumulation if eaten with aspirin, such as curry powder, paprika, or licorice (approximately 6 mg salicylate/100 g food); effects may decrease with antacids and urinary alkalinizers; corticosteroids decrease salicylate serum levels; may antagonize uricosuric effects of probenecid and increase toxicity of phenytoin and valproic acid; doses >2 g/d may potentiate glucose lowering effect of sulfonylurea drugs; simultaneous administration of other NSAIDs may decrease the cardioprotective and stroke preventive effects

Documented hypersensitivity; liver damage, hypoprothrombinemia, vitamin K deficiency, bleeding disorders, asthma; due to association of aspirin with Reye syndrome, do not use in children (<16 y) with viral infections

Pregnancy

C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus

Precautions

Pregnancy category D in third trimester; caution while breastfeeding; may cause excessive hemorrhage and gastrointestinal ulceration; watch for transient decrease in renal function and aggravated chronic kidney disease; avoid use in severe anemia or history of blood coagulation defects


Anagrelide (Agrylin)

Inhibits post mitotic megakaryocyte maturation. Unlike hydroxyurea, selectively inhibits platelet proliferation. In polycythemia vera used only to control platelet counts, but shows slight decrease in mean hemoglobin and hematocrit while white cell counts maintained. Inhibits cyclic nucleotide phosphodiesterase and the release of arachidonic acid from phospholipase, possibly by inhibiting phospholipase A2. Can be used in addition to hydroxyurea for particularly difficult to control thrombocytosis in polycythemia vera.

Adult

1 mg/d PO initially; adjust to lowest effective dose that maintain platelet count; not to exceed 10 mg/d

Pediatric

Not established; limited data suggest pediatric dose similar to adults

Sucralfate may decrease absorption (1 case report); may increase effects of drotrecogin alpha, NSAIDs, salicylates, treprostinil, and other antiplatelet agents; use herbal medicines with caution (can have anticoagulant or antiplatelet effects)

Pregnancy

C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus

Precautions

Common adverse effects include thrombocytopenia are headaches, palpitations, fluid retention, and diarrhea; caution with renal or hepatic impairment

Antineoplastic Agent

These agents are used off-label for polycythemia, but pediatric doses are extrapolated from pediatric treatment regimens, including leukemia and myelodysplastic syndrome.


Hydroxyurea (Droxia, Hydrea)

Nonalkylating, myelosuppressive, S-phase agent. Inhibits ribonucleotide reductase, the enzyme that converts ribonucleotides into deoxynucleotides, thereby depleting deoxynucleotide and inhibiting DNA synthesis. Cellular proliferation is ultimately inhibited, and leukocytes, erythrocytes, and platelets are decreased. The mechanism of action is probably different than the one exerted by hydroxyurea in the treatment of sickle cell disease. A misconception is that hydroxyurea is leukemogenic. No studies have conclusively demonstrated that hydroxyurea is more leukemogenic than baseline in myeloproliferative disease.

Adult

Dose varies and ranges from 500 mg/d PO to as high as needed to control erythrocytosis and as tolerated by the leukocyte and platelet counts

Pediatric

15 mg/kg/d PO initially, adjust dose based on response; dosage based on patient's actual or ideal weight, whichever is less

Coadministration with fluorouracil can increase neurotoxicity; infections may result in immunosuppressed patients who receive immunizations with live virus vaccines (eg, MMR); coadministration with didanosine has caused fatal and nonfatal pancreatitis; coadministration with other myelosuppressive agents may increase toxicity

Documented hypersensitivity; severe pancytopenia (WBC <2.5 X 109/L, platelets <100 X 109/L, severe anemia)

Pregnancy

D - Fetal risk shown in humans; use only if benefits outweigh risk to fetus

Precautions

Caution in renal impairment; dose limiting myelosuppression with variable anemia and thrombocytopenia may occur; may cause nausea and GI upset; reliable birth control (both men and women) is required during treatment; avoid while breastfeeding (secreted in human milk)

More on Polycythemia Vera

Overview: Polycythemia Vera
Differential Diagnoses & Workup: Polycythemia Vera
Treatment & Medication: Polycythemia Vera
Follow-up: Polycythemia Vera
Multimedia: Polycythemia Vera
References
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References

  1. Baxter EJ, Scott LM, Campbell PJ, et al. Acquired mutation of the tyrosine kinase JAK2 in human myeloproliferative disorders. Lancet. Mar 19-25 2005;365(9464):1054-61. [Medline].

  2. Nussenzveig RH, Swierczek SI, Jelinek J, et al. Polycythemia vera is not initiated by JAK2V617F mutation. Exp Hematol. Jan 2007;35(1):32-8. [Medline].

  3. Vannucchi AM, Antoniolim E, Guglielmelli P, et al. Plenary session. ASH Annual Meeting Abstracts. Blood. 2006;108.

  4. Silver RT. Interferon alfa: effects of long-term treatment for polycythemia vera. Semin Hematol. Jan 1997;34(1):40-50. [Medline].

  5. Silver RT. Recombinant interferon-alpha for treatment of polycythaemia vera. Lancet. Aug 13 1988;2(8607):403. [Medline].

  6. Carobbio A, Finazzi G, Antonioli E, et al. JAK2V617F allele burden and thrombosis: a direct comparison in essential thrombocythemia and polycythemia vera. Exp Hematol. Sep 2009;37(9):1016-21. [Medline].

  7. Berk PD, Wasserman LR, Fruchtman SM. Treatment of polycythemia vera: a summary of clinical trials conducted by the polycythemia vera study group. In: Wasserman LR, Berk PD, Berlin NI, eds. Polycythemia vera and the myeloproliferate disorders. Philadelphia: WB Saunders; 1995:166.

  8. Marchioli R, Finazzi G, Landolfi R, Kutti J, Gisslinger H, Patrono C. Vascular and neoplastic risk in a large cohort of patients with polycythemia vera. J Clin Oncol. Apr 1 2005;23(10):2224-32. [Medline].

  9. Patel RK, Lea NC, Heneghan MA, Westwood NB, Milojkovic D, Thanigaikumar M. Prevalence of the activating JAK2 tyrosine kinase mutation V617F in the Budd-Chiari syndrome. Gastroenterology. Jun 2006;130(7):2031-8. [Medline].

  10. Thurmes PJ, Steensma DP. Elevated serum erythropoietin levels in patients with Budd-Chiari syndrome secondary to polycythemia vera: clinical implications for the role of JAK2 mutation analysis. Eur J Haematol. Jul 2006;77(1):57-60. [Medline].

  11. [Guideline] Spivak JL, Silver RT. The revised World Health Organization diagnostic criteria for polycythemia vera, essential thrombocytosis, and primary myelofibrosis: an alternative proposal. Blood. Jul 15 2008;112(2):231-9. [Medline].

  12. Kondo T, Okuno N, Naruse H, et al. Validation of the revised 2008 WHO diagnostic criteria in 75 suspected cases of myeloproliferative neoplasm. Leuk Lymphoma. Sep 2008;49(9):1784-91. [Medline].

  13. Di Nisio M, Barbui T, Di Gennaro L, et al. The haematocrit and platelet target in polycythemia vera. Br J Haematol. Jan 2007;136(2):249-59. [Medline].

  14. Landolfi R, Marchioli R, Kutti J, Gisslinger H, Tognoni G, Patrono C. Efficacy and safety of low-dose aspirin in polycythemia vera. N Engl J Med. Jan 8 2004;350(2):114-24. [Medline].

  15. Kiladjian JJ, Cassinat B, Turlure P, et al. High molecular response rate of polycythemia vera patients treated with pegylated interferon alpha-2a. Blood. Sep 15 2006;108(6):2037-40. [Medline].

  16. Adamson JW, Fialkow PJ, Murphy S, Prchal JF, Steinmann L. Polycythemia vera: stem-cell and probable clonal origin of the disease. N Engl J Med. Oct 21 1976;295(17):913-6. [Medline].

  17. Ang SO, Prchal JT. The polycythemia vera and other polycythemic disorders: biological aspects. In: Melo JV, Goldman JM, eds. Myeloproliferative Diseases. New York, NY: Springer-Verlag; 2006:297-319.

  18. Finazzi G, Barbui T. How I treat patients with polycythemia vera. Blood. Jun 15 2007;109(12):5104-11. [Medline].

  19. Fisher MJ, Prchal JF, Prchal JT, D'Andrea AD. Anti-erythropoietin (EPO) receptor monoclonal antibodies distinguish EPO-dependent and EPO-independent erythroid progenitors in polycythemia vera. Blood. Sep 15 1994;84(6):1982-91. [Medline].

  20. Fruchtman SM, Mack K, Kaplan ME, Peterson P, Berk PD, Wasserman LR. From efficacy to safety: a Polycythemia Vera Study group report on hydroxyurea in patients with polycythemia vera. Semin Hematol. Jan 1997;34(1):17-23. [Medline].

  21. Hino M, Futami E, Okuno S, Miki T, Nishizawa Y, Morii H. Possible selective effects of interferon alpha-2b on a malignant clone in a case of polycythemia vera. Ann Hematol. Mar 1993;66(3):161-2. [Medline].

  22. Hoffman R, Prchal JT, Samuelson S, Ciurea SO, Rondelli D. Philadelphia chromosome-negative myeloproliferative disorders: biology and treatment. Biol Blood Marrow Transplant. Jan 2007;13(1 Suppl 1):64-72. [Medline].

  23. Kralovics R, Guan Y, Prchal JT. Acquired uniparental disomy of chromosome 9p is a frequent stem cell defect in polycythemia vera. Exp Hematol. Mar 2002;30(3):229-36. [Medline].

  24. Kralovics R, Passamonti F, Buser AS, et al. A gain-of-function mutation of JAK2 in myeloproliferative disorders. N Engl J Med. Apr 28 2005;352(17):1779-90. [Medline].

  25. Landolfi R, Di Gennaro L, Barbui T, De Stefano V, Finazzi G, Marfisi R. Leukocytosis as a major thrombotic risk factor in patients with polycythemia vera. Blood. Mar 15 2007;109(6):2446-52. [Medline].

  26. Liu E, Jelinek J, Pastore YD, Guan Y, Prchal JF, Prchal JT. Discrimination of polycythemias and thrombocytoses by novel, simple, accurate clonality assays and comparison with PRV-1 expression and BFU-E response to erythropoietin. Blood. Apr 15 2003;101(8):3294-301. [Medline].

  27. Messora C, Bensi L, Vecchi A, et al. Cytogenetic conversion in a case of polycythaemia vera treated with interferon-alpha. Br J Haematol. Feb 1994;86(2):402-4. [Medline].

  28. Prchal JF, Axelrad AA. Letter: Bone-marrow responses in polycythemia vera. N Engl J Med. Jun 13 1974;290(24):1382. [Medline].

  29. Prchal JT, Beutler E. Primary and secondary polycythemias (erythrocytosis). In: Lichtman MA, Beutler E, Kaushansky K, Kipps TJ, Seligsohn U, Prchal JT, eds. Williams Hematology. New York: McGraw-Hill; 2005.

  30. Tefferi A, Thiele J, Orazi A, et al. Proposals and rationale for revision of the World Health Organization diagnostic criteria for polycythemia vera, essential thrombocythemia, and primary myelofibrosis: recommendations from an ad hoc international expert panel. Blood. Aug 15 2007;110(4):1092-7. [Medline].

  31. Ugo V, James C, Vainchenker W. [A unique clonal JAK2 mutation leading to constitutive signalling causes polycythaemia vera]. Med Sci (Paris). Jun-Jul 2005;21(6-7):669-70. [Medline].

  32. Ugo V, Marzac C, Teyssandier I, et al. Multiple signaling pathways are involved in erythropoietin-independent differentiation of erythroid progenitors in polycythemia vera. Exp Hematol. Feb 2004;32(2):179-87. [Medline].

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Further Reading

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Keywords

polycythemia vera, PV, primary polycythemia, polycythemia rubra vera, PRV, Osler-Vaquez disease, erythremia, splenomegalic polycythemia, erythrocytosis megalosplenica, cryptogenic polycythemia, anemia, thrombocytosis, leukocytosis, leukemia, deep venous thrombosis, Budd-Chiari syndrome, congestive heart failure, peptic ulcer disease, congestive heart failure, pulmonary hypertension, acute myeloid leukemia, treatment, diagnosis

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Contributor Information and Disclosures

Author

Josef T Prchal, MD, FRCP, Professor of Medicine (Hematology), Adjunct Professor of Pathology and Genetics, University of Utah School of Medicine
Josef T Prchal, MD, FRCP is a member of the following medical societies: American College of Physicians, American Society of Human Genetics, and Southern Society for Clinical Investigation
Disclosure: Nothing to disclose.

Coauthor(s)

Scott J Samuelson, MD, Fellow in Hematology and Oncology, Huntsman Cancer Institute, University of Utah School of Medicine
Scott J Samuelson, MD is a member of the following medical societies: American College of Physicians-American Society of Internal Medicine and American Society of Hematology
Disclosure: Nothing to disclose.

Medical Editor

Sharada A Sarnaik, MBBS, Professor of Pediatrics, Wayne State University School of Medicine; Director, Sickle Cell Center, Attending Hematologist/Oncologist, Children's Hospital of Michigan
Sharada A Sarnaik, MBBS is a member of the following medical societies: American Association of Blood Banks, American Association of University Professors, American Society of Hematology, American Society of Pediatric Hematology/Oncology, New York Academy of Sciences, and Society for Pediatric Research
Disclosure: Nothing to disclose.

Pharmacy Editor

Mary L Windle, PharmD, Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy, Pharmacy Editor, eMedicine
Disclosure: Pfizer Inc Stock Investment from financial planner; Avanir Pharma Stock Investment from financial planner ; WebMD Salary and stock Employment and investment from financial planner

Managing Editor

James L Harper, MD, Associate Professor, Department of Pediatrics, Division of Hematology/Oncology and Bone Marrow Transplantation, Associate Chairman for Education, Department of Pediatrics, University of Nebraska Medical Center; Assistant Clinical Professor, Department of Pediatrics, Creighton University; Director, Continuing Medical Education, Children's Memorial Hospital; Pediatric Director, Nebraska Regional Hemophilia Treatment Center
James L Harper, MD is a member of the following medical societies: American Academy of Pediatrics, American Association for Cancer Research, American Federation for Clinical Research, American Society of Hematology, American Society of Pediatric Hematology/Oncology, Council on Medical Student Education in Pediatrics, and Hemophilia and Thrombosis Research Society
Disclosure: Nothing to disclose.

CME Editor

Helen SL Chan, MBBS, FRCP(C), FAAP, Senior Scientist, Research Institute; Professor, Division of Hematology/Oncology, Department of Pediatrics, The Hospital for Sick Children, University of Toronto, Canada
Helen SL Chan, MBBS, FRCP(C), FAAP is a member of the following medical societies: American Academy of Pediatrics, American Association for Cancer Research, American Society of Hematology, and Royal College of Physicians and Surgeons of Canada
Disclosure: Nothing to disclose.

Chief Editor

Robert J Arceci, MD, PhD, King Fahd Professor of Pediatric Oncology, Professor of Pediatrics, Oncology and the Cellular and Molecular Medicine Graduate Program, Kimmel Comprehensive Cancer Center at Johns Hopkins University School of Medicine
Robert J Arceci, MD, PhD is a member of the following medical societies: American Association for Cancer Research, American Association for the Advancement of Science, American Pediatric Society, American Society of Hematology, and American Society of Pediatric Hematology/Oncology
Disclosure: Nothing to disclose.

 
 
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