title: Myeloid Cell Nuclear Differentiation Antigen (MNDA) Expression Distinguishes Extramedullary Presentations of Myeloid Leukemia From Blastic Plasmacytoid Dendritic Cell Neoplasm.
abstract: Myeloid neoplasms constitute one of the most common malignancies in adults. In most cases these proliferations initially manifest in the blood and marrow; however, extramedullary involvement may precede blood or marrow involvement in a subset of cases, making a definitive diagnosis challenging by morphologic and immunohistochemical assessment alone. Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare, aggressive entity that frequently presents in extramedullary sites and can show morphologic and immunophenotypic overlap with myeloid neoplasms. Given that BPDCN and myeloid neoplasms may both initially present in extramedullary sites and that novel targeted therapies may be developed that exploit the unique molecular signature of BPDCN, new immunophenotypic markers that can reliably separate myeloid neoplasms from BPDCN are desirable. We evaluated the utility of myeloid cell nuclear differentiation antigen (MNDA) expression in a series of extramedullary myeloid leukemias (EMLs) and BPDCN. Forty biopsies containing EML and 19 biopsies containing BPDCN were studied by MNDA immunohistochemistry. The majority of myeloid neoplasms showed nuclear expression of MNDA (65%). In contrast, all cases of BPDCN lacked MNDA expression. These findings show that MNDA is expressed in the majority of EMLs and support the inclusion of MNDA immunohistochemistry in the diagnostic evaluation of blastic hematopoietic infiltrates, particularly when the differential diagnosis is between myeloid leukemia and BPDCN.
authors.affiliation: *Department of Pathology, Stanford University, Stanford, CA †Department of Pathology, The Ohio State University, Columbus, OH ‡Department of Pathology, Oregon Health & Science University, Portland, OR.
authors.forename: Ryan C
authors.initials: RC
authors.lastname: Johnson
authors.forename: Jinah
authors.initials: J
authors.lastname: Kim
authors.forename: Yasodha
authors.initials: Y
authors.lastname: Natkunam
authors.forename: Uma
authors.initials: U
authors.lastname: Sundram
authors.forename: Aharon G
authors.initials: AG
authors.lastname: Freud
authors.forename: Bryan
authors.initials: B
authors.lastname: Gammon
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Cascio
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015214:Antigens, Differentiation, Myelomonocytic / Q000032:analysis / Q000096:biosynthesis*; D014408:Biomarkers, Tumor / Q000032:analysis*; D002648:Child; D003713:Dendritic Cells / Q000473:pathology*; D003937:Diagnosis, Differential; D005260:Female; D019337:Hematologic Neoplasms / Q000175:diagnosis*; D006801:Humans; D007150:Immunohistochemistry; D016130:Immunophenotyping; D007951:Leukemia, Myeloid / Q000175:diagnosis*; D008297:Male; D008875:Middle Aged; D014157:Transcription Factors / Q000032:analysis / Q000096:biosynthesis*; D055815:Young Adult
chemical_list: D015214:Antigens, Differentiation, Myelomonocytic; D014408:Biomarkers, Tumor; C075373:MNDA protein, human; D014157:Transcription Factors