Copyright ©The Author(s) 2015.
World J Hematol. Aug 6, 2015; 4(3): 16-53
Published online Aug 6, 2015. doi: 10.5315/wjh.v4.i3.16
Table 10 World Health Organization-clinical molecular and pathological criteria for hypercellular essential thrombocythemia associated with primary megakaryocytic, granulocytic myeloproliferation caused by calreticulin mutations[78]
Clinical CM criteria JAK2 wild type PMGMPathological ECP criteria of CALR MGM
A1 No preceding or allied other subtype of myeloproliferative neoplasm PV, CML, MDS. The main presenting features is pronounced isolated thrombocythemia with platelet count around or above 1000 × 109/LP1 PMGM and relative or absolute reduction of erythropoiesis and erythroid precursors. Abnormal dense clustering and increase in atypical medium sized, large to giant immature megakaryocytes containing bulbous (cloud-like) hypolobulated nuclei and definitive maturation defects
A2 Presence of CALR mutation and JAK2 wild type
C Clinical stages of CALR MGMMF Grading RF, MF
C1 Early clinical stage: Hb > 12 g/dL, slight to moderate splenomegaly, thrombocytosis around or above 1000 × 109/L, normal LAP scoreMF 0 Prefibrotic CALR MGM, no reticulin fibrosis RF 0/1
C2 Intermediate clinical stage: slight anemia Hb < 12 to > 10 g/dL, decreasing platelet count, splenomegaly, increased LDH and definitive tear drop erythrocytesMF 1 Early fibrotic CALR MGM slight reticulin fibrosis RF 2
C3 Advanced stage: anemia Hb < 10 g/dL, tear drop erythrocytes, increased LDH, increased CD34+ cells, pronounced splenomegaly, normal or decreased platelet counts, leucocytosis or leukopeniaMF 2 Fibrotic CALR MGM increase RF grade 3 and slight to moderate collagen fibrosis
MF 3 Advanced fibrotic CALR MGM with collagen fibrosis-osteosclerosis