TY - JOUR T1 - Myoepithelial cells in solid variant of intraductal papillary carcinoma of the breast: a potential diagnostic pitfall and a proposal of an immunohistochemical panel in the differential diagnosis with intraductal papilloma with usual ductal hyperplasia. AU - Moritani,Suzuko, AU - Ichihara,Shu, AU - Kushima,Ryoji, AU - Okabe,Hidetoshi, AU - Bamba,Masamichi, AU - Kobayashi,Tadao K, AU - Hattori,Takanori, Y1 - 2007/03/22/ PY - 2006/11/13/received PY - 2007/03/03/accepted PY - 2007/02/28/revised PY - 2007/3/23/pubmed PY - 2007/8/29/medline PY - 2007/3/23/entrez SP - 539 EP - 47 JF - Virchows Archiv : an international journal of pathology JO - Virchows Arch VL - 450 IS - 5 N2 - We examined myoepithelial status in intraductal papillary carcinoma (IPC) along with the expression of high-molecular weight cytokeratin (HMWK) and neuroendocrine markers, with special reference to the differential diagnosis of solid intraductal papillary carcinoma(SIPC) and intraductal papilloma with usual ductal hyperplasia (IP-UDH). Twenty-six (93%) of the twenty-eight intraductal papillomas (IP) had myoepithelial cells in >70% of the epithelial-stromal interface of the intraluminal proliferating component. Six (29%) of twenty-one SIPC had almost complete myoepithelial layer like IP-UDH at the epithelial-stromal interface. HMWK (34 beta E-12) was diffusely positive in 14 (93%) of 15 IP-UDH, but 16 (76%) of 21 SIPC were completely negative for HMWK. Neuroendocrine markers were positive in 14 (67%) of SIPC, but all 28 IPs were completely negative. If only the presence of myoepithelial cells is emphasized as a benign hallmark, about 30% of SIPCs may be underdiagnosed as IP-UDH. However, by using a combination of myoepithelial markers, HMWK, and neuroendocrine markers, all of the 36 solid intraductal papillary lesions were properly classified as benign and malignant. Solid intraductal papillary lesions meeting at least two of the following criteria are highly likely to be malignant: (1) absence of myoepithelial cells(<10% of epithelial-stromal interface of intraluminal proliferating component), (2) negative HMWK(<10%), (3) positive neuroendocrine markers (>10%). SN - 0945-6317 UR - https://www.unboundmedicine.com/medline/citation/17377808/Myoepithelial_cells_in_solid_variant_of_intraductal_papillary_carcinoma_of_the_breast:_a_potential_diagnostic_pitfall_and_a_proposal_of_an_immunohistochemical_panel_in_the_differential_diagnosis_with_intraductal_papilloma_with_usual_ductal_hyperplasia_ L2 - https://dx.doi.org/10.1007/s00428-007-0402-y DB - PRIME DP - Unbound Medicine ER -