Barriers to diagnosis of MPNs

Factors that may pose barriers to the diagnosis of MPNs include:

  • The relatively rare nature of these conditions1
  • The nonspecific nature of symptoms, which can overlap with other benign conditions, such as fibromyalgia or autoimmune disorders.2 For example:
    • A patient with PV who has concomitant iron deficiency might be diagnosed with ET because iron deficiency can reduce hemoglobin/hematocrit levels below those required for the diagnosis of PV3
    • A patient with prefibrotic PMF could be labeled as someone who has ET, particularly when a bone marrow biopsy is not performed, because both entities can present with thrombocytosis2,4
    • Patients with different MPNs may have similar signs and symptoms, such as bone pain, pruritus, and splenomegaly; however, the presence of certain constitutional symptoms (weight loss, night sweats) should be considered when a diagnosis of an MPN is suspected5

Another potential problem is the variability in the interpretation of the bone marrow findings.6 For example, observer-dependent variability in estimating the degree of fibrosis in the bone marrow or identifying dysplasia that may be affecting the megakaryocytic lineage may have an impact on the eventual diagnosis.6 Ideally, a diagnosis will be made by the hematologist/oncologist working with the hematopathologist to combine the findings of the clinical history and the bone marrow biopsy.

References
  1. Mehta J, Wang H, Fryzek JP, et al. Leuk Lymphoma. 2014;55(3):595-600.
  2. Vardiman JW, Thiele J, Arber DA, et al. Blood. 2009;114(5):937-951.
  3. Parthasarathy V. Case Rep Hematol. 2012;2012:826939.
  4. Tefferi A, Vardiman JW. Leukemia. 2008;22(1):14-22.
  5. Mesa RA, Niblack J, Wadleigh M, et al. Cancer. 2007;109(1):68-76.
  6. Buhr T, Hebeda K, Kaloutsi V, et al. Haematologica. 2012;97(3):360-365.