The c3-a2 type of BCR/ABL junction seems to be associated with elevated platelet count and thus could form a novel clinical entity different from typical CML.
There is controversy over the proper classification of thrombocytosis associated with the pathological BCR-ABL gene rearrangement; such cases are not clearly distinguishable from chronic myelogenous leukemia (CML) and should be provisionally classified as CML.
This long-sought common mutation in BCR/ABL1-negative MPD raises many provocative biological and clinical questions, and demands re-evaluation of prevailing diagnostic algorithms for erythrocytosis and thrombocytosis.
In agreement with published data, our results showed association of the BCR-ABL1 transcript e14a2 with thrombocytosis and the BCR-ABL1 transcript e13a2 with higher leukocytosis in patients with chronic myeloid leukemia.
Among 84 consecutive patients with chronic phase Ph-positive chronic myeloid leukemia (CML) who were investigated for the hybrid BCR/ABL mRNA, in six cases (7%) the disease mimicked essential thrombocythemia (ET) at presentation, because of marked thrombocytosis (platelet counts ranging from 1003 x 10(9)/l to 2800 x 10(9)/l) and moderate leukocytosis (WBC counts from 10 x 10(9)/l to 19 x 10(9)/l).