title: Histological features of medullary carcinoma and prognosis in triple-negative basal-like carcinomas of the breast.
abstract: Medullary carcinomas have a better prognosis than other grade 3 mammary carcinomas, but they typically show basal-like biological features, which are associated with a poor prognosis. In this study we examined the associations and prognostic relevance of medullary histological features in a series of 165 invasive carcinomas with a basal-like phenotype: triple-negative (oestrogen receptor, progesterone receptor, HER2) and expressing at least one basal marker (CK5/6, CK14, CK17 or EGFR). The following histological features were associated with each other: prominent inflammation, anastomosing sheets, absence of fibrosis, absence of infiltrative margin and absence of gland formation. Prominent inflammation and anastomosing sheets in at least 30% of the tumour were associated with a better prognosis on univariate analysis. The combination of these two features (a simplified definition of medullary-like type) was present in 17% of tumours and was an independent prognostic factor on multivariate analysis. This simplified definition had good inter-observer reproducibility (κ=0.61) and is worthy of more detailed assessment in an unselected group of mammary carcinomas. A fibrotic focus was present in 36% of carcinomas. Only 3% of tumours with a fibrotic focus had features of medullary-like carcinomas. Fibrotic focus of greater than 30% of the tumour was associated with a poor prognosis. This study emphasizes the heterogeneity of morphology and behaviour of triple-negative basal-like carcinomas.
authors.affiliation: Department of Histopathology, Nottingham University Hospitals, Nottingham, UK.
authors.forename: Felicia
authors.initials: F
authors.lastname: Marginean
authors.forename: Emad A
authors.initials: EA
authors.lastname: Rakha
authors.forename: Bernard C
authors.initials: BC
authors.lastname: Ho
authors.forename: Ian O
authors.initials: IO
authors.lastname: Ellis
authors.forename: Andrew H S
authors.initials: AH
authors.lastname: Lee
mesh_terms: D000368:Aged; D014408:Biomarkers, Tumor / Q000032:analysis; D001943:Breast Neoplasms / Q000235:genetics / Q000401:mortality / Q000473:pathology*; D018276:Carcinoma, Medullary / Q000235:genetics / Q000401:mortality / Q000473:pathology*; D066246:ErbB Receptors / Q000096:biosynthesis; D005260:Female; D018734:Genes, erbB-2; D006801:Humans; D016130:Immunophenotyping; D053208:Kaplan-Meier Estimate; D053547:Keratin-14 / Q000096:biosynthesis; D053537:Keratin-17 / Q000096:biosynthesis; D053555:Keratin-5 / Q000096:biosynthesis; D053553:Keratin-6 / Q000096:biosynthesis; D008875:Middle Aged; D011379:Prognosis; D011960:Receptors, Estrogen / Q000096:biosynthesis / Q000235:genetics; D011980:Receptors, Progesterone / Q000096:biosynthesis / Q000235:genetics
chemical_list: D014408:Biomarkers, Tumor; D053547:Keratin-14; D053537:Keratin-17; D053555:Keratin-5; D053553:Keratin-6; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; D066246:ErbB Receptors