Case Report
Copyright ©The Author(s) 2020. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Clin Cases. Nov 26, 2020; 8(22): 5618-5624
Published online Nov 26, 2020. doi: 10.12998/wjcc.v8.i22.5618
Primary myelofibrosis with concurrent CALR and MPL mutations: A case report
Feng-Ping Zhou, Cheng-Cheng Wang, Hua-Ping Du, Shan-Bo Cao, Jin Zhang
Feng-Ping Zhou, Hua-Ping Du, Jin Zhang, Department of Hematology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou 310016, Zhejiang Province, China
Cheng-Cheng Wang, Shan-Bo Cao, Acornmed Biotechnology Co., Ltd., Beijing 100176, China
Author contributions: All authors contributed to the study conception and design; Zhou FP and Wang CC prepared the material and collected and analyzed the data; Du HP diagnosed and treated the patient; Cao SB analyzed the NGS data; Zhang J revised the manuscript for important intellectual content; all authors approved the final version of the manuscript.
Informed consent statement: The patient provided informed written consent during the treatment.
Conflict-of-interest statement: The authors declare that they have no conflicts of interest to disclose.
CARE Checklist (2016) statement: The authors have read the CARE Checklist (2016), and the manuscript was prepared and revised according to the CARE Checklist (2016).
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Corresponding author: Jin Zhang, MD, Attending Doctor, Department of Hematology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, No. 3 East Qingchun Road, Hangzhou 310016, Zhejiang Province, China. zfpingzd@zju.edu.cn
Received: April 5, 2020
Peer-review started: April 5, 2020
First decision: September 24, 2020
Revised: October 6, 2020
Accepted: October 19, 2020
Article in press: October 19, 2020
Published online: November 26, 2020
Processing time: 233 Days and 22.5 Hours
Abstract
BACKGROUND

Primary myelofibrosis (PMF) is a myeloproliferative neoplasm (MPN) characterized by recurrent mutations in the JAK2, CALR, and MPL genes. The CALR and MPL co-mutation is very rare. To our knowledge, no more than five cases have been reported. Here, we report a case of PMF in which a CALR and MPL co-mutation was detected by next-generation sequencing (NGS) technology, and a literature review was performed.

CASE SUMMARY

A 73-year-old woman was admitted to our hospital in 2018 due to abdominal distension. The patient had splenomegaly, lymphadenopathy, leukopenia, anemia, and immature granulocytes in peripheral blood. There were dacrocytes and atypical megakaryocytes in bone marrow, and megakaryocytic proliferation was very active, accompanied by reticulin fibrosis grade 2. By NGS analysis of the bone marrow sample, we detected mutations in CALR, MPL, and PIK3RI, while JAK2 V617F and BCR-ABL were negative. Therefore, the patient was diagnosed with PMF and received oral ruxolitinib. However, the spleen and hematologic responses were poor. We review the literature, analyze previous reports of the mutation sites in our patient and differences between our patient and other reported cases of co-mutated CALR and MPL genes, and discuss the reason why the CALR and MPL co-mutations are rare and possible mechanisms and their impact on the prognosis of patients.

CONCLUSION

CALR and MPL mutations can be concurrent in MPN, but they are rare. The use of NGS may help to identify more patients with co-mutated CALR and MPL genes. This will help to further explore the mechanism and its impact on these patients to develop appropriate treatment strategies.

Keywords: Primary myelofibrosis; CALR; MPL; Co-mutation; Next-generation sequencing; Case report

Core Tip: We report a rare case of primary myelofibrosis in which a CALR and MPL co-mutation was detected by next-generation sequencing technology. It demonstrated that CALR and MPL mutations can be concurrent in myeloproliferative neoplasm. We review the literature, analyze previous reports of the mutation sites in our patient and differences between our patient and other reported cases of co-mutated CALR and MPL genes, and discuss the reason why the CALR and MPL co-mutations are rare and possible mechanisms and their impact on the prognosis of patients.