Cytogenetic correlates of TET2 mutations in 199 patients with myeloproliferative neoplasms
TET2 is a putative tumor suppressor gene located at chromosome 4q24. TET2 mutations were recently described in several myeloid neoplasms but correlations with cytogenetic findings have not been studied. Among a recently described cohort of patients with myeloproliferative neoplasms (MPN) who underwent TET2 mutation analysis, 199 had information on karyotype at diagnosis or time of TET2 testing: 71 polycythemia vera (PV), 55 primary myelofibrosis (PMF), 43 essential thrombocythemia (ET), 13 post-PV MF, 7 post-ET MF, and 10 blast phase MPN. Forty eight patients (24%) exhibited abnormal karyotype: 15 favorable (sole 20q-, 13q-, or +9), 8 unfavorable (complex karyotype or sole +8), and 25 "other" cytogenetic abnormalities. We found no significant difference either in the incidence or type of cytogenetic abnormalities between TET2 mutated (n = 25) and unmutated (n = 174) cases. Seventy nine patients, including 14 with TET2 mutations, underwent follow-up cytogenetic testing and the findings were again not affected by TET2 mutational status. We conclude that TET2 mutated MPN patients are not cytogenetically different than their TET2 unmutated counterparts.