NCI Definition: A slowly progressing leukemia characterized by a clonal (malignant) proliferation of maturing and mature myeloid cells or mature lymphocytes. When the clonal cellular population is composed of myeloid cells, the process is called chronic myelogenous leukemia. When the clonal cellular population is composed of lymphocytes, it is classified as chronic lymphocytic leukemia, hairy cell leukemia, or T-cell large granular lymphocyte leukemia. [1]

Chronic leukemias most frequently harbor alterations in ABL1, BRAF, BCR, TET2, and ASXL1 [2].

Most Commonly Altered Genes in Chronic Leukemia

BRAF V600E, BRAF Mutation, BRAF Exon 15 Mutation, BRAF Codon 600 Missense, and BCR-ABL1 Fusion are the most common alterations in chronic leukemia [2].

Top Alterations in Chronic Leukemia

Disease Details

Hairy Cell Leukemia, Chronic Lymphocytic Leukemia, Chronic Eosinophilic Leukemia with FIP1L1-PDGFRA, Aggressive NK-Cell Leukemia, Prolymphocytic Leukemia, T-Cell Large Granular Lymphocyte Leukemia, Hairy Cell Leukemia Variant, Chronic Myeloid Leukemia, Chronic Neutrophilic Leukemia, and Chronic Eosinophilic Leukemia, NOS


1. National Cancer Institute. NCI Thesaurus Version 18.11d. https://ncit.nci.nih.gov/ncitbrowser/ [2018-08-28]. [2018-09-21].

2. The AACR Project GENIE Consortium. AACR Project GENIE: powering precision medicine through an international consortium. Cancer Discovery. 2017;7(8):818-831. Dataset Version 8. This dataset does not represent the totality of the genetic landscape; see paper for more information.

3. All assertions and clinical trial landscape data are curated from primary sources. You can read more about the curation process here.