Successful Treatment of a Patient with Chronic Myelogenous Leukemia with Concurrent Janus Kinase 2 (JAK2) R795S Mutation and Breakpoint Cluster Region-ABL1 (BCR-ABL1) Fusion: A Case Report and Literature Review.

Abstract

BACKGROUND Although the V617F mutation in the Janus kinase 2 (JAK2) gene and the breakpoint cluster region-abl1 (BCR-ABL1) oncogene fusion have been considered mutually exclusive in most myeloproliferative neoplasms (MPNs), many recent studies have described patients with both. This report describes a patient with chronic myelogenous leukemia (CML) and the unusual JAK2 R795S mutation and reviews 23 additional patients with JAK2 gene mutations coexisting with myelofibrosis (MF) and CML. CASE REPORT A 50-year-old woman with MF experienced rapid disease progression 3 weeks later, accompanied by severe abdominal pain and a white blood cell count of 257.45×10⁹/l. Karyotype analysis indicated that she was 46, XY, Philadelphia (Ph) (+) and BCR-ABL1 positive. Bone marrow aspiration after 1 cycle of chemotherapy and treatment with dasatinib showed that her marrow was hypercellular, with an increased number of megakaryocytes and 48.5% myeloblasts expressing the myeloid antigens CD33, CD13, CD34, CD117, and CD71. Next-generation sequencing identified a rare JAK2 R795S mutation. She was diagnosed with CML in blast phase, and was successfully treated with allogeneic hematopoietic stem cell transplantation (allo-HSCT). CONCLUSIONS JAK2 gene mutations, including the rare JAK2 R795S mutation, can coexist with BCR-ABL1 in patients with MPNs. The clinical course of MPN in patients with both BCR-ABL1 and JAK2 mutations may be different from that in patients with classical MPNs.

• Authors: Yanhua Yue, Wei Wei, Yanting Guo, Fei Wang, Weimin Dong, Yue Liu, Yan Lin, Yang Cao, Weiying Gu
• Journal: The American journal of case reports (Am J Case Rep) Vol. 21 Pg. e925151 (Oct 06 2020) ISSN: 1941-5923 [Electronic] United States
• PMID: 33021971 (Publication Type: Case Reports, Journal Article, Review)

Chemical References

• JAK2 protein, human
• Janus Kinase 2

Topics

• Female
• Humans
• Janus Kinase 2 (genetics)
• Leukemia, Myelogenous, Chronic, BCR-ABL Positive (genetics, therapy)
• Middle Aged
• Mutation
• Myeloproliferative Disorders (genetics, therapy)
• Primary Myelofibrosis