ABSTRACT
Despite recent discoveries made in myeloproliferative disorders other than chronic
myelogenous leukemia, which it is hoped will result in earlier diagnosis, and better
evaluation and management of patients, hematological evolution to myelofibrosis, acute
leukemia, and myelodysplastic syndromes (AL/MDS) remain major causes of long-term
mortality in polycythemia vera (PV) and essential thrombocythemia (ET) patients. Evaluation
of long-term leukemogenic risk of currently available drugs, therefore, is crucial.
We report updated results of three French prospective trials of hydroxyurea and pipobroman
in PV and ET patients with a median follow-up longer than 10 years. The results show
that the incidence of AL/MDS is higher than previously reported with no evidence of
a plateau (with ~40% of AL/MDS cases occurring after the 12th year of follow-up).
Although hydroxyurea currently remains the first choice in the treatment of high-risk
PV and ET patients, the use of nonleukemogenic drugs, such as interferon α (IFN-α)
or anagrelide, should be assessed more widely in randomized trials using accurate
diagnostic criteria and taking into account the presence of the JAK2 mutation, given
that they may have an impact on disease evolution.
KEYWORDS
Polycythemia vera - essential thrombocythemia - leukemogenic risk - hydroxyurea -
anagrelide - interferon - pipobroman
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Jean-Jacques KiladjianM.D.
Hopital Avicenne and Paris 13 University, Service d'Hematologie clinique
125, route de Stalingrad, 93000 Bobigny, France
eMail: jean-jacques,kiladjian@avc.aphp.fr