The Clinical Challenge of Idiopathic Cytopenias of Undetermined Significance (ICUS) and Clonal Cytopenias of Undetermined Significance (CCUS)

AbstractPurpose of ReviewTo review terminology, diagnostic algorithms, and clinical outcomes for patients with unexplained blood cytopenias.Recent FindingsPatients with cytopenias that remain unexplained after organized diagnostic testing can be described as having “idiopathic cytopenias of undetermined significance” (ICUS). Patients with unexplained cytopenias have a risk of progression to clonal myeloid neoplasms, including myelodysplastic syndromes (MDS). If a somatic mutation in a gene associated with leukemia is detectable in hematopoietic tissue, esp ecially if multiple mutations with a high (>  10%) variant allele frequency are present, the risk of progression to frank neoplasia is greater than if such mutations are not detected. These patients can be described with the term, “clonal cytopenias of undetermined significance” (CCUS). CCUS patients have a natural history similar to low er-risk MDS.SummaryFor patients with unexplained cytopenias, longitudinal follow-up including serial monitoring of blood counts is appropriate in view of the progression risk. Genetic testing may aid in risk stratification.
Source: Current Hematologic Malignancy Reports - Category: Hematology Source Type: research