Unusual chromosome aberration, t(13;14)(q32;q32.3), in a case of essential thrombocythemia with extreme thrombocytosis

A case of essential thrombocythemia (ET) with extreme thrombocytosis in a 70-year-old male patient is described. The cytogenetic analysis revealed a pathologic clone with the following previously unreported, unusual karyotype: 46,XY,t(13;14)(q32;q32.3) and pericentric inversion of chromosome 9. The possible association of t(13;14) with the high platelet count is discussed.