Fluorescence in situ hybridization (FISH) of TP53 for the detection of chromosome 17 abnormalities in myelodysplastic syndromes

Conventional G-banding cytogenetics (CC) detects chromosome 17 (chr17) abnormalities in 2% of patients with de novo myelodysplastic syndromes (MDS). We used CC and fluorescence in situ hybridization (FISH) (LSI p53/17p13.1) to assess deletion of 17p in 531 patients with de novo MDS from the Spanish Group of Hematological Cytogenetics. FISH detected17 or 17p abnormalities in 13 cases (2.6%) in whom no 17p abnormalities were revealed by CC: 9% of patients with a normal karyotype, 0% in non-informative cytogenetics, 50% of patients with a chr17 abnormality without loss of 17p and in 4.7% of cases with an abnormal karyotype not involving chr17. Our results suggest that applying FISH of 17p13 to identify the number of copies of the TP53 gene could be beneficial in patients with a complex karyotype. We recommend using FISH of 17p13 in young patients with a normal karyotype or non-informative cytogenetics, and always in isolated del(17p

Characterization and prognostic implication of 17 chromosome abnormalities in myelodysplastic syndrome

The prognosis of chromosome 17 (chr17) abnormalities in patients with primary myelodysplastic syndrome (MDS) remains unclear. The revised International Prognostic Scoring System (IPSS-R) includes these abnormalities within the intermediate cytogenetic risk group.This study assessed the impact on overall survival (OS) and risk of acute myeloid leukemia transformation (AMLt) of chr17 abnormalities in 88 patients with primary MDS. We have compared this group with 1346 patients with primary MDS and abnormal karyotype without chr17 involved. The alterations of chr17 should be considered within group of poor prognosis. The different types of alterations of chromosome 17 behave different prognosis. The study confirms the intermediate prognostic impact of the i(17q), as stated in IPSS-R. The results of the study, however, provide valuable new information on the prognostic impact of alterations of chromosome 17 in complex karyotypes