Myeloproliferative neoplasm
Myeloproliferative neoplasm | |
---|---|
Other names | Myeloproliferative diseases (MPDs) |
Myelogram of someone with a myeloproliferative disorder. | |
Specialty | Hematology and oncology |
Myeloproliferative neoplasms (MPNs) are a group of rare blood cancers in which excess red blood cells, white blood cells or platelets are produced in the bone marrow. Myelo refers to the bone marrow, proliferative describes the rapid growth of blood cells and neoplasm describes that growth as abnormal and uncontrolled.
The overproduction of blood cells is often associated with a somatic mutation, for example in the JAK2, CALR, TET2, and MPL gene markers.
In rare cases, some MPNs such as primary myelofibrosis may accelerate and turn into acute myeloid leukemia.[1]
Classification
MPNs are classified as blood cancers by most institutions and organizations.[2] In MPNs, the neoplasm (abnormal growth) starts out as benign and can later become malignant.
As of 2016, the World Health Organization lists the following subcategories of MPNs:[3]
- Chronic myeloid leukemia(CML)
- Chronic neutrophilic leukemia (CNL)
- Polycythemia vera (PV)
- Primary myelofibrosis (PMF)
- Essential thrombocythemia (ET)
- Chronic eosinophilic leukemia (not otherwise specified)
- MPN, unclassifiable (MPN-U)
Causes
MPNs arise when
Diagnosis
People with MPNs might not have symptoms when their disease is first detected via blood tests.
Chronic myeloid leukemia
Chronic neutrophilic leukemia
Chronic neutrophilic leukemia (CNL) is characterized by a mutation in the CSF3R gene and an exclusion of other causes of neutrophilia.
Essential thrombocythemia
Essential thrombocythemia (ET) is diagnosed with a platelet count greater than 450 × 109/L and is associated with the JAK2 V617F mutation in up to 55% of cases[10] and with an MPL (thrombopoietin receptor) mutation in up to 5% of cases:.[11] There should be no increase in reticulin fibers and the patient should not meet the criteria for other MPNs, in particular Pre-PMF.
Polycythemia vera
Polycythemia vera (PV) is associated most often with the JAK2 V617F mutation greater than 95% of cases, whereas the remainder has a JAK2 exon 12 mutations. High hemoglobin or hematocrit counts are required, as is a bone marrow examination showing "prominent erythroid, granulocytic and megakaryocytic proliferation with pleomorphic, mature megakaryocytes."
Prefibrotic/early primary myelofibrosis
Prefibrotic primary myelofibrosis (Pre-PMF) is typically associated with JAK2, CALR, or MPL mutations and shows reticulin fibrosis no greater than grade 1. Anemia, splenomegaly, LDH above the upper limits and leukocytosis are minor criteria.[12]
Overtly fibrotic myelofibrosis
Like
MPN-U
Patients with otherwise unexplained thrombosis and with neoplasms that cannot be classified in one of the other categories.
Treatment
No curative drug treatment exists for MPNs.[13] Hematopoietic stem cell transplantation can be a curative treatment for a small group of patients, however MPN treatment is typically focused on symptom control and myelosuppressive drugs to help control the production of blood cells.[citation needed]
The goal of treatment for ET and PV is prevention of thrombohemorrhagic complications. The goal of treatment for MF is amelioration of anemia, splenomegaly, and other symptoms. Low-dose aspirin is effective in PV and ET.
Recently, a Trials of these inhibitors are in progress for the treatment of the other myeloproliferative neoplasms.
Incidence
Although considered rare diseases, incidence rates of MPNs are increasing, in some cases tripling. It is hypothesized that the increase may be related to improved diagnostic abilities from the identification of the JAK2 and other gene markers, as well as continued refinement of the WHO guidelines.[16]
There is wide variation in reported MPN incidence and prevalence worldwide, with a publication bias suspected for essential thrombocythemia and primary myelofibrosis.[17]
History
The concept of myeloproliferative disease was first proposed in 1951 by the
MPNs were classified as blood cancers by the World Health Organization in 2008.[20] Previously, they were known as myeloproliferative diseases (MPD).
In 2016, Mastocytosis was no longer classified as an MPN.[21]
References
- ^ "Preventing Myelofibrosis from Progressing to Acute Myeloid Leukemia". Cure Today. Retrieved 2023-02-18.
- ^ "Are Myeloproliferative Neoplasms (MPNs) Cancer?". #MPNresearchFoundation. Archived from the original on 2020-07-11. Retrieved 2020-07-10.
- PMID 27069254.
- PMID 30285359. Retrieved 8 July 2021.
- – via Science Direct.
- ^ "Symptoms, Diagnosis, & Risk Factors | Seattle Cancer Care Alliance". www.seattlecca.org. Retrieved 2020-07-10.
- ISBN 0-443-06377-X.
- PMID 27449473.
- PMID 29426921.
- S2CID 36419846.
- PMID 18451306.
- ^ Mesa, Reuben. "What is Prefibrotic Primary Myelofibrosis?". Patient Power. HealthCentral LLC. Retrieved 23 June 2023.
- ^ "Summary". www.meduniwien.ac.at. Archived from the original on 2022-05-23. Retrieved 2020-07-09.
- PMID 21220604.
- S2CID 16010648.
- S2CID 19156436.
- PMID 24971434.
- PMID 14820991.
- ^ "Understanding MPNs- Overview | MPNRF". #MPNresearchFoundation. Retrieved 2020-07-10.
- ^ "Myeloproliferative Neoplasms". Cancer Support Community.
- PMID 29426921.
External links
- Myeloproliferative+Disorders at the U.S. National Library of Medicine Medical Subject Headings (MeSH)
- MPN Info via Cancer.gov