Prognostic impact of c-KIT mutations in core binding factor leukemias: an Italian retrospective study.
Cairoli R, Beghini A, Grillo G, Nadali G, Elice F, Ripamonti CB, Colapietro P, Nichelatti M, Pezzetti L, Lunghi M, Cuneo A, Viola A, Ferrara F, Lazzarino M, Rodeghiero F, Pizzolo G, Larizza L, Morra E. Division of Hematology, Ospedale Niguarda, Piazza Ospedale Maggiore 3, 20162-Milano, Italy. roberto.cairoli@ospedaleniguarda.it

Distinct forms of tyrosine kinase domain (TKD), juxtamembrane domain, exon 8, and internal tandem duplication (ITD) mutations of c-KIT, were observed in about 46% of core binding factor leukemia (CBFL) patients. To evaluate their prognostic significance, 67 adult patients with CBFL were analyzed to ascertain the c-KIT mutation status. In acute myeloid leukemia (AML) with t(8;21), the presence of c-KIT TKD mutation at codon 816 (TKD(816)) was associated with a high white blood cell count at diagnosis (median, 29.60 x 10(9)/L) and a higher incidence (33%) of extramedullary leukemia (EML) during the course of the disease. Data also showed that the TKD(816) mutated patients (n = 12) had a significantly higher incidence of relapse and a lower overall survival (OS) at 24 months, compared with the 17 c-KIT unmutated (c-KIT(-)) patients (90% vs 35.3%, P = .002; 25% vs 76.5%, P = .006, respectively). No difference in relapse incidence (P = .126) and OS (P = .474) was observed between the c-KIT mutated other than TKD(816) (n = 7) and the c-KIT(-) patients. These findings indicate that c-KIT TKD(816) mutation has a negative impact on the outcome of AML with t(8;21).

PMID: 16384925 [PubMed - indexed for MEDLINE]