NRP1 and B-cell acute lymphoblastic leukemia: Previous studies had explored the diagnostic or prognostic value of NRP‐1/CD304 in blastic plasmacytoid dendritic cell neoplasm (BPDCN), acute myeloid leukemia (AML), and B‐cell acute lymphoblastic leukemia (B‐ALL), whereas the expression and application value of NRP‐1/CD304 in other common hematological diseases have not been reported.