title: Tubular carcinoma and grade 1 (well-differentiated) invasive ductal carcinoma: comparison of flat epithelial atypia and other intra-epithelial lesions.
abstract: The distinction between tubular carcinomas (TC) and invasive well-differentiated (grade 1) ductal carcinoma (IDC) is important given treatment and prognostic differences. Studies have described a strong association between flat epithelial atypia (FEA) and TC. The incidence of FEA associated with grade 1 IDC is not well established. The aim of the present study was to assess morphology and intra-epithelial lesions between 14 TC and 18 grade 1 IDC matched for size. Of 14 TC, eight (57%) had associated FEA, seven (50%) had micropapillary atypical ductal hyperplasia (ADH), three (21%) had low nuclear grade ductal carcinoma in situ (DCIS), and four (29%) had lobular neoplasia. Notably, only two of 18 (11%) grade 1 IDC had associated FEA. Three of 18 (16%) grade 1 IDC had ADH, two (11%) had lobular neoplasia, and seven (39%) had DCIS. All tubular carcinomas were estrogen receptor (ER) positive and negative for Her-2/neu overexpression. All grade 1 IDC were ER positive but 5% also overexpressed Her-2/neu. Axillary lymph node metastasis was present in 11% of grade 1 IDC and absent in TC. A strong association was found between TC, FEA, and micropapillary ADH, which may reflect a biological progression. Despite matching for tumor size, grade 1 IDC have a higher incidence of lymph node metastasis and may have Her-2-neu overexpression compared to TC.
authors.affiliation: Department of Pathology, University of Michigan School of Medicine, Ann Arbor, Michigan 48109, USA.
authors.forename: Lakshmi P
authors.initials: LP
authors.lastname: Kunju
authors.forename: Ying
authors.initials: Y
authors.lastname: Ding
authors.forename: Celina G
authors.initials: CG
authors.lastname: Kleer
mesh_terms: D000230:Adenocarcinoma / Q000378:metabolism / Q000473:pathology*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000378:metabolism; D001943:Breast Neoplasms / Q000378:metabolism / Q000473:pathology*; D018270:Carcinoma, Ductal, Breast / Q000378:metabolism / Q000556:secondary*; D002285:Carcinoma, Intraductal, Noninfiltrating / Q000378:metabolism; D002467:Cell Nucleus / Q000378:metabolism / Q000473:pathology; D004847:Epithelial Cells / Q000473:pathology; D005260:Female; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D008198:Lymph Nodes / Q000473:pathology; D008207:Lymphatic Metastasis; D008875:Middle Aged; D011379:Prognosis; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism; D011960:Receptors, Estrogen / Q000378:metabolism; D011980:Receptors, Progesterone / Q000378:metabolism
chemical_list: D014408:Biomarkers, Tumor; D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; C508053:ERBB2 protein, human