ESSENTIAL THROMBOCYTHEMIA - A RETROSPECTIVE ANALYSIS OF 39 CASES

Thirty-nine Chinese patients presenting as essential thrombocythemia ( ET) were analyzed retrospectively. The median age at presentation was 69 years and the M:F ratio was 1.35:1. At diagnosis, 33 cases (84%) we re asymptomatic and the diagnosis was made incidentally while 3 cases (8%) presented with small vessel, and 2 cases (5%) with large vessel, thrombosis. One patient (3%) presented with minor breeding. The platel et count ranged from 0.9-34 x 10(12)/I. Of 12 karyotypes done, 2 cases were abnormal, both showing the Philadelphia (Ph) chromosome. First-l ine therapy was radiophosphorus (P-32) in 3 cases, melphalan in 20 cas es, and hydroxyurea in 12 cases; 4 cases did not receive specific ther apy. During the follow-up (mean = 4 years), no thrombotic or bleeding episodes were observed. One patient with the Ph chromosome underwent b lastic transformation. These results indicate that bleeding and thromb osis occur significantly less in Chinese patients than in Western pati ents. The Ph chromosome appears to be a bad prognostic indicator. Beca use of the very low incidence of complications and good prognosis, the authors believe that cytoreductive therapy is best achieved by the us e of hydroxyurea instead of alkylating agents or radiophorphours, as t he latter agents are potentially leukemogenic. (C) 1995 Wiley-Liss, In c.