Prognostic relevance of cytogenetics determined by fluorescent in situ hybridization in patients having myelofibrosis with myeloid metaplasia

BACKGROUND. in chronic myelofibrosis (MF), distinct recurrent cytogenetic aberrations have been identified but their true prognostic relevance remains uncertain. In this disease, cytogenetic studies as assessed by conventional metaphase karyo-typing are limited due to the inherent difficulties in obtaining adequate bone marrow aspirates and the low proliferative capacity of the clonal cells. Interphase fluorescent in situ hybridization (FISH) can partly overcome these limitations and increase the sensitivity of cytogenetic assessment in MF. METHODS. We retrospectively analyzed formalin-fixed, paraffin embedded bone marrow sections of 107 MF patients by FISH and correlated cytogenetic findings with clinical presentation and survival. RESULTS. Chromosomal aberrations were detected in 56% of patients, with 20q- (24.3%) and 13q- (16.8%) being the most frequent ones. Importantly, cytogenetic abnormalities were found in 8/17 patients displaying a normal karyotype as assessed by conventional cytogenetics. CONCLUSIONS. Cytogenetic abnormalities in patients with MF can be detected reliably using FISH. Rare abnormalities confer an adverse outcome, but the main recurrent chromosomal aberrations do not correlate with clinical features and prognosis.