The category name is changed from the prior “myeloid and lymphoid neoplasms with eosinophilia (M/LN-eo) and gene rearrangement” to “Myeloid/lymphoid neoplasms with eosinophilia and tyrosine kinase gene fusions” (M/LN-eo-TK) by both WHO-HAEM5 and ICC (Table 8). The gene discussed is TKT; the disease is Increased total eosinophil count.