CLEC4C and CD4+/CD56+ hematodermic neoplasm: Julia et al. suggested that a diagnosis of BPDCN is made by positive immunoreactivity for four of five markers (CD4, CD56, CD123, CD303, and TCL1 [T-cell leukemia/lymphoma 1]) and revealed that approximately 50% of patients showed simultaneous expression of these five markers [11].