Abstract
Big data from large international cooperations allow proving consistency of findings in national patient cohorts. We compared features in NRAS-mutated patients of the Austrian biodatabase for chronic myelomonocytic leukemia (ABCMML) with the chronic myelomonocytic leukemia (CMML) cohort documented in cBioPortal. It is consistently demonstrated in both CMML cohorts that NRAS mutations are associated with shorter overall survival, acute myeloid leukemia-free survival, increased white blood cell count, decreased platelet values and the presence of blast cells in peripheral blood. Hemoglobin values did not differ between patients with or without NRAS mutations in either cohort. Validation of data in CMML patients using two independent cohorts, ensures the quality standards for clinical decision making.