Table 3 Pre-fibrotic /early primary myelofibrosis (Pre-PMF) (WHO refs. # [4,5,6,7] versus ICC ref. # [14]).
Year Major criteria | 2001 Jaffe ES et al. ref. # [4] | 2008 Swerdlow SH et al. ref. # [5] | 2017 Swerdlow SH et al. ref. # [6] | 2024 Akkari Y et al. ref.# [7] | 2022 Arber DA. et al. ref. # [14] |
|---|---|---|---|---|---|
Blood | No or mild leukoerythroblastosis, no or minimal red blood cell poikilocytosis, few if any dacrocytes | ||||
Bone marrow morphology | Hypercellularity, Neutrophilic proliferation, Megakaryocytic proliferation and atypia (clustering of megakaryocytes, abnormally lobulated megakaryocytic nuclei, naked megakaryocytic nuclei). Minimal or absent reticulin fibrosis | Presence of megakaryocytic proliferation and atypia in the absence of significant reticulin fibrosis accompanied by an increased bone marrow cellularity characterized by granulocytic proliferation and often decreased erythropoiesis (i.e., pre-fibrotic cellular phase of disease) | Megakaryocytic proliferation and atypia, without reticulin fibrosis grade >1 accompanied by increased age-adjusted bone marrow cellularity, granulocytic proliferation, and (often) decreased erythropoiesis | Megakaryocytic proliferation and atypia, without reticulin fibrosis grade >|1, accompanied by increased age-adjusted bone marrow cellularity, granulocytic proliferation, and (often) decreased erythropoiesis | Bone marrow biopsy showing megakaryocytic proliferation and atypia, bone marrow fibrosis grade<2, increased age-adjusted BM cellularity, granulocytic proliferation, and (often) decreased erythropoiesis |
Criteria of Exclusion | Not meeting WHO criteria for polycythemia vera, BCR::ABL1 positive chronic myeloid leukemia, myelodysplastic syndromes or other myeloid neoplasms | WHO criteria for polycythemia vera, BCR::ABL1 positive chronic myeloid leukemia, myelodysplastic syndromes or other myeloid neoplasms are not met | WHO criteria for BCR :: ABL1–positive chronic myeloid leukemia, polycythemia vera,essential thrombocythemia, myelodysplastic syndromes, or other myeloid neoplasms are not met | Diagnostic criteria for BCR::ABL1 positive CML, PV, ET, myelodysplastic syndromes, or other myeloid neoplasms are not met | |
Clonal genetic abnormality | Demonstration of JAK2 V617F or other clonal marker (e.g. MPL W515K/L), or in the absence of a clonal marker, no evidence that the bone marrow fibrosis or other changes are secondary to infection, autoimmune disorder or other chronic inflammatory condition, hairy cell leukemia or other lymphoid neoplasm, metastatic malignancy, or toxic (chronic) myelopathies | JAK2, CALR, or MPL mutation or presence of another clonal marker or absence of minor reactive bone marrow reticulin fibrosis | JAK2, CALR, or MPL mutation or presence of another clonal marker or absence of minor reactive bone marrow reticulin fibrosis | JAK2, CALR, or MPL mutation or presence of another clonal marker or absence of reactive bone marrow reticulin fibrosis | |
Minor Criteria | Hematologic parameters variable but often: mild anemia, mild to moderate leukocytosis, mild to marked thrombocytosis, no or mild splenomegaly or hepatomegaly | Leukoerythroblastosis Increase in serum lactate dehydrogenase level Anemia Splenomegaly (degree of abnormality may be borderline) | Presence of at least one of the following, confirmed in 2 consecutive determinations: Anemia not attributed to comorbid condition Leukocytosis ≥ 11 × 10 9/L Palpable splenomegaly Serum lactate dehydrogenase level above the upper limit of the institutional reference range | Presence of at least one of the following, confirmed in 2 consecutive determinations: Anemia not attributed to comorbid condition: Leukocytosis ≥ 11 × 109/ L; Splenomegaly detected clinically and/or by imaging; Lactate serum dehydrogenase level above the upper limit of the institutional reference range; Leukoerythroblastosis | Anemia not attributed to a comorbid condition Leukocytosis ≥ 11×109/L Palpable splenomegaly Lactate serum dehydrogenase level above the reference range |
Diagnosis requires meeting criteria 1 and 2 and criteria of exclusion | Diagnosis requires meeting all 3 major and 2 minor criteria | The diagnosis of pre-fibrotic/ early primary myelofibrosis requires that all 3 major and at least 1 minor criterion are met | The diagnosis of pre-fibrotic primary myelofibrosis requires that all 3 major criteria and at least 1 minor criterion are met. | The diagnosis of pre-PMF requires all 3 major criteria and at least 1 minor criterion confirmed in 2 consecutive determinations |
