AbstractBackgroundPrevious 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.MethodsBone marrow samples from 297 newly diagnosed patients with various hematological diseases were collected to detect the expression of NRP‐1/CD304 by flow cytometry (FCM). The diagnostic efficacy of NRP‐1/ CD304‐positive diseases was analyzed by receiver operating characteristic (ROC) curve, and the area under the ROC curve (AUC) was compared.ResultsIn the research cohort, the total positive rate of NRP‐1/CD304 was 14.81% (44/297), mainly distributed in BPDCN (100%, 6/6), B‐ALL (48.61%, 35/72), and AML (4.48%, 3/67), with statistically significant differences (p< 0.01). Other diseases, such as T‐cell acute lymphoblastic leukemia (T‐ALL), B‐cell non‐Hodgkin lymphoma (B‐NHL), T/NK‐cell lymphoma and plasma cell neoplasms, did not express NRP‐1/CD304. The AUC of NRP‐1/CD304 was 0.936 (95% CI 0.898–0.973), 0.723 (95% CI 0.646–0.801), and 0.435 (95% CI 0.435) in BPDCN, B‐ALL and AML, respectively. Besides, CD304 was commonly expressed in B‐ALL with BCR‐ABL1 gene rearrangement (p= 0.000), and CD304 expression was positively correlated with CD34 co‐expression (p= 0.009) and CD10 co‐expression (p= 0.007).ConclusionsNRP‐1/CD304 is only expressed in BPDCN, B‐ALL and AML, but not in other common hematological diseases. This indicates that NRP‐1/CD304 has no obvious diagnostic and follow‐up study value in hematological diseases other than BPDCN, B‐ALL, and AML.