MPN Acronyms – abbreviations and some commonly used terms in discussion of Myeloproliferative Neoplasms

Alkylator Drugs that chemically modify DNA cells to destroy them by adding alkyl groups. Agents include busulfan, pipobroman and chlorambucil.
ALL Acute Lymphocytic Leukemia excess of lymphoblasts, most common type of cancer in children, cure rate in them is 80% and adults up to 60%.
AML Acute Myeloid Leukemia most common type of acute leukemia; phases are measured by levels of abnormal immature white cells (blasts): chronic phase- < 10% blasts, accelerated phase 10-19% blasts, blast phase 20+% blasts; blast crisis 20% blasts with fever, fatigue and enlarged spleen.
AMM Agnogenic Myeloid Metaplasia or Chronic Idiopathic Myelofibrosis obsolete term; now usually called primary myelofibrosis see MF, IMF, PMF.
BCR-ABL Philadelphia Chromosome translocation (see Ph) to form the oncogene which causes CML.
Blood-thinner Agent used to prevent clotting old standard is warfarin, a vitamin K antagonist, requiring frequent monitoring and sensitive to diet and drug interactions. New drugs include Pradaxa dabigatran, Eliquis apixaban and Xarelto rivaroxaban. These are thrombin factor IIa or Xa inhibitors so diet and drug interactions are minimal and monitoring is not required. They are more robust stroke preventers than warfarin and reduce intracranial bleeding.
BM Bone Marrow Biopsy removal of aspirate and solid tissue from marrow for analysis. Can be done under local anesthetic, or with “conscious sedation” to ensure a minimum of discomfort from the procedure.
BMT Bone Marrow Transplant, the only cure for an MPN, but is expensive and comes with high risk. ABMT autologous bone marrow transplant your own marrow. Generally not used in MPNs. BMT allogeneic bone marrow transplant someone else’s marrow MUD-bone marrow transplant marrow from matched unrelated donor SBMT-syngeneic bone marrow transplant identical twin’s marrow PBPC peripheral blood progenitor cell transplant PBSCT peripheral blood stem cell transplant PBSCR peripheral blood stem cell rescue PSCT or PSCR same as above without the word “blood.”
CBC Complete Blood Count called Full Blood Count (FBC) in some countries. See Hct, Hg or Hgb, MCH, MCHC, MCV, PT/PL, RBC, RDW, WBC, WCC.
CD Cluster of Differentiation system of classifying lymphocytes according to antigen collections on their cell surfaces, also called CD markers, eg rituximab destroys B cells that have CD20 antigen on their surface.
CML Chronic Myelogenous Leukemia also called chronic myeloid leukemia; the Philadelphia chromosome is present in 90+% of patients with high white cell counts (up to 100 to 300), and in those where it isn’t present, the BCR-ABL fusion gene is generally identifiable. Since granulocytes are involved in this type of leukemia, it is also referred to as CGL or chronic granulocytic leukemia.
DNA Deoxyribonucleic Acid the cell nucleus material that contains genetic instructions.
EPO Erythropoietin a hormone controlling red cell production; it promotes RBC survival by protecting from apoptosis (programmed suicide cell death).
ERC Erythrocyte cell count (see RBC).
ET Essential Thrombocythemia/thrombocytosis MPN variant where platelet count is over 400.
FISH Fluorescence In Situ Hybridization an analytical technique: a fluorescent probe that detects DNA sequences in situ (in normal position within a chromosome) and thereby detects abnormalities.
GVHD Graft-Versus-Host Disease complication of allogeneic BMT in which immune cells in the transplanted marrow treat the recipient’s tissues (the patient’s) as foreign and cause an immunologic attack.
Hb/Hg/Hgb Hemoglobin oxygen carrying component in red blood cells. Labs report the concentration in grams of hemoglobin in one liter of blood although some report it in 100 milliliters (one deciliter). Normal female 12-16 g/deciliter, male 14-18 g/deciliter (ie 120-160, and 140-180 g/l) (see RBC).
Hct Hematocrit the percentage by volume of whole blood that consists of blood cells (the remainder is plasma). Measured in a centrifuged test tube; also called PCV packed cell volume or EVF-erythrocyte volume fraction; reference range for females is approximately 33-43; for males 40-53; quoted as a decimal number by some laboraties (ie 0.40-0.53).
HLA and HLA typing and matching Human leukocyte antigen (HLA) typing is used to match patients and donors for allogeneic bone marrow transplants. HLA are proteins or markers found on most cells in your body. A close match between your HLA markers and your donor’s can reduce the risk that your immune cells will attack your donor’s cells or that your donor’s immune cells will attack your body after the transplant. If you need an allogeneic transplant (which uses cells from a family member, unrelated donor or cord blood unit), your doctor will take a blood sample to test for your HLA type. (Acknowledgement from
HT Hemorrhagic Thrombocythemia term applied to ET with bleeding episodes.
HU Hydroxyurea (hydroxycarbamide) oral chemotherapeutic agent used to treat elevated blood counts in MPNs. It has a low incidence of secondary leukemias and cancers compared to P32 and alkylating agents, and has been the gold standard treatment for MPNs until the advent of Interferon in its various forms.
IMF Idiopathic myelofibrosis; see PMF
IFN Interferon a protein produced by the body when exposed to a virus; recombinant alpha-interferon forms are used in MPNs. Can produce lasting remissions and allow patients treatment-free periods. Roferon and Intron A are the main brand options, Peg-Intron and Pegasys are sustained release forms now more commonly used. All forms of Interferon are administered via subcutaneous injection.
INR International Normalized Ratio test measuring time it takes blood to clot compare to an average; target range for warfarin dosing 2.0-3.0.
JAK2V617F Genetic mutation found in majority of MPN patients: PV>95%, ET & PMF around 50%.
JAK-STAT Janus Kinase-Signal Transducer & Activator of Transcription a signal transduction pathway, ie the molecular-level messaging that occurs within cells; STATs are phosphorylated by JAKs, go into cell nuclei, bind to specific elements and induce gene transcription.
Kinases Enzymes also called phosphotransferases they transfer phosphate groups to proteins which then act as on-off switches in many biochemical systems.
LKC Leukocyte count number of white cells in a given volume of blood.
INR International Normalized Ratio test measuring time it takes blood to clot compare to an average; target range for warfarin dosing 2.0-3.0.
-mab generic name suffix indicating drug is a Monoclonal AntiBody; e.g. rituximab.
MCH Mean Cell Hemoglobin Average weight of hemoglobin in the red blood cell; normal 27-33 pg (picograms).
MCHC Mean cell hemoglobin concentration % of average red cell which is filled with hemoglobin; normal 33.1-35.6.
MCV Mean Cell Volume average size of the red cells. MCV tends to be low if treated by phlebomoties, as iron deficiency, the goal of phlebotomies, causes red cells to be of smaller average size; normal range 80-100 fL (femtoliters, or 1×10 to minus 15th power of a liter).
MDS Myelodysplastic Syndrome previously “preleukemia”, or “smouldering leukemia”; a diverse collection of conditions involving ineffective production (dysplasia) of the myeloid class of blood cells; closely related to, but different from, MPNs.
MF Myelofibrosis replacement of normal marrow with useless fibrous tissue. See PMF, sMF.
MMM Myelofibrosis with Myeloid Metaplasia MF with involvement of other organs spleen and liver most commonly become the sites of blood-producing cells, in an attempt to compensate for reduced bone marrow effectiveness due to fibrosis.
MPD Myeloproliferative diseases; now called Myeloproliferative neoplasms MPNs.
MPN Myeloproliferative Neoplasms chronic bone marrow cancers (leukemias): ET, MF, PV(all without the Philadelphia Chromosome ie Ph negative), CML (Philadelphia Chromosome positive, Ph +ve), mast cell disorders, systemic mastocytosis. MPDs were renamed “neoplasms” in 2008, after a review and reclassification of myeloid malignancies.
-nib Generic name suffix indicating drug is an antineoplastic; eg. Ruxolitinib.
P32 Radioactive Phosphorus injectable therapy to suppress high blood counts; mainly used in the elderly, as a higher rate of leukemia can occur.
PEG-Intron Pegylated Interferon alfa-2b polyethylene glycol sustained release form (see IFN).
Pegasys Pegylated Interferon alfa-2a polyethylene glycol sustained release form; fewer side effects than non-pegylated (normal) Interferon (see IFN).
Ph Philadelphia Chromosome abnormality associated with CML (sometimes ALL) caused by translocation between chromosomes 9 and 22; see BCR-ABL.
PMF Primary (or idiopathic) myelofibrosis. One of the three main non-Philadelphia chromosome MPNs (with ET and PV).
PPMMM Postpolycythemic Myelofibrosis with Myeloid Metaplasia; commonly referred to as secondary MF see sMF.
PL/platelets Platelet count the number of platelets in a given volume of blood. Either quoted as per liter (eg, reference range of 150-400 x 109 per liter) or per microliter (reference range of 150,000-400,000).
PT Prothrombin Time measures time for blood to clot after addition of tissue factor.
PV (PRV) Polycythemia Vera (Polycythemia Rubra Vera) MPN variant with increased hematocrit, red cell count, increased blood volume and viscosity; white cells and platelets can also be raised.
RBC Red Blood Cell count Normal female 3.9-5.2; male 4.2-5.6 (both number of cells, times 10 to the 12th, per liter).
RCM Red Cell Mass test for volume/mass of circulating red blood cells used to confirm diagnosis of PV; normal males 24-32 mL/kg, females 21-27. Rarely used now as JAK2 and EPO tests generally preferred.
RDW Red Cell Volume Distribution Width degree to which red cells vary in size from one another; normal 10.9-13.7 (Mayo Clinic).
RLS restless leg syndrome. Commonly associated with iron deficiency in MPNs.
SCT Stem Cell Transplant a BMT in which stem cells from the peripheral blood are used.
sMF Myelofibrosis occurring as a progression from another of the MPNs, generally following PV, ET, or CML.
SP Secondary Polycythemia high hemoglobin and hematocrit. Can be caused by smoking, high altitude, chronic heart, lung or kidney disease; resolves when cause removed, or underlying disease is treated. Driven by an increase in the cytokine EPO, produced by the kidneys when oxygen levels are chronically low.
TIBC Total Iron Binding Capacity test of blood’s capacity to bind iron to transferrin; normal 240-450 micrograms/deciliter.
TPO Thrombopoietin hormone that regulates megakaryocyte (platelet precursors) production, and thus platelets; it operates through its receptor (Mpl) to stimulate production.
VWD (vWD) von Willebrand Disease bleeding disorder caused by deficiency of VWFactor which helps platelets clump and stick to blood vessel walls; usually hereditary but Acquired VWD may occur in ET due to sequestration of Factor by adhesion to the high number of platelets.
WBC White Blood Cell Count normal range 4-11×109 per liter (ie 4-11 billion cells per liter, sometimes quoted as 4000-11,000 per microliter). The precise range varies slightly between laboratories and regions.

Compiled by R Niblack,G Gjerde and I Sweet. Enquiries and comments should be sent to