Features of KRAS-mutated patients with chronic myelomonocytic leukemia with and without blast transformation in a national (ABCMML) and international cohort (BIOPORTAL).

Big data collected in large international cooperations nowadays allow validation of findings from traditional national patient cohorts for proving consistency. In this study we compared findings in KRAS-mutated patients of the Austrian biodatabase for chronic myelomonocytic leukemia (ABCMML) with that from the CMML cohort documented in cBioPortal. It was consistently shown in both CMML cohorts that KRAS mutations were not associated with shorter overall and acute myeloid leukemia (AML)-free survival. In both cohorts, phenotypic features such as leukocytes, hemoglobin, and circulating blasts were not significantly different between patients with and without KRAS mutations. However, the proportion of patients with thrombocytopenia was higher in KRAS-mutated patients in the BIOPORTAL cohort but not in the ABCMML cohort. The percentage of KRAS mutations significantly increased in blast transformation (from 9.8 to 21.7%), as shown in the ABCMML cohort. These data may suggest a pathogenetic role of KRAS mutations in CMML-associated AML.