Essential thrombocythemia--clinical features, therapy and follow-up of 12 cases.

The authors analyzed twelve patients with symptomatic essential throthrombocythemia (E.T.) diagnosed from 1983 to 1991. Haemorrhagic and thrombotic phenomena were the main presenting features. Treatment consisted mostly of alpha-interferon (IFN-alpha 2b) subcutaneously in dosage ranging from 3 to 5 MU/m2 and hydroxyurea (HU) in conventional dosage. A clinical response was seen in seven patients treated with IFN-alpha 2b (4 CR and 2 PR), and in four patients treated with HU (3 CR and 1 PR). No significant side effects were observed. Our findings indicate that IFN-alpha 2b offers a non-leukaemogenic and very promising therapeutic alternative for E.T.