title: Solid variant of mammary "adenoid cystic carcinoma with basaloid features" merging with "small cell carcinoma".
abstract: We describe a rare case of a solid variant of a mammary adenoid cystic carcinoma with basaloid features (sbACC) and its coexistence with a "small cell" carcinoma (SCC), identified and confirmed by histological and immunohistochemical observations: the absence of glandular structures and PAS-positive globules, positivity for neuroendocrine markers (NSE, synaptophysin and chromogranin), and negativity for 34betaE12 and SMA actin were the aspects suggesting the presence of SCC. Furthermore, positivity for CD10 was found both in sbACC and in SCC, supporting the hypothesis that the two components share the same histogenetic myoepithelial origin and represent an example of dedifferentiation along neuroendocrine phenotype lines occurring in a multipotential neoplastic stem line, already committed towards a myoepithelial phenotype. To our knowledge, this is the first reported case of a solid basaloid adenoid cystic carcinoma merging with an SCC carcinoma. Furthermore, it is the first study in which CD10 was used to investigate the histogenesis of the two neoplastic components.
authors.affiliation: Institute of Pathology, A.O.U. Policlinico Paolo Giaccone, Via del Vespro 129, 90127 Palermo, Italy. cabibidaniela@virgilio.it
authors.forename: Daniela
authors.initials: D
authors.lastname: Cabibi
authors.forename: Calogero
authors.initials: C
authors.lastname: Cipolla
authors.forename: Ada
authors.initials: A
authors.lastname: Maria Florena
authors.forename: Salvatore
authors.initials: S
authors.lastname: Fricano
authors.forename: Elisabetta
authors.initials: E
authors.lastname: Barresi
authors.forename: Salvatore
authors.initials: S
authors.lastname: Vieni
authors.forename: Vito
authors.initials: V
authors.lastname: Rodolico
authors.forename: Liborio
authors.initials: L
authors.lastname: Napoli
mesh_terms: D000328:Adult; D001365:Axilla; D014408:Biomarkers, Tumor / Q000032:analysis; D001943:Breast Neoplasms / Q000737:chemistry / Q000473:pathology* / Q000628:therapy; D003528:Carcinoma, Adenoid Cystic / Q000737:chemistry / Q000473:pathology* / Q000628:therapy; D002280:Basal Cell Carcinoma / Q000737:chemistry / Q000473:pathology* / Q000628:therapy; D018288:Carcinoma, Small Cell / Q000737:chemistry / Q000473:pathology* / Q000628:therapy; D017024:Chemotherapy, Adjuvant; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008197:Lymph Node Excision; D015412:Mastectomy, Segmental; D009378:Neoplasms, Multiple Primary / Q000737:chemistry / Q000473:pathology* / Q000628:therapy; D010503:Periodic Acid-Schiff Reaction
chemical_list: D014408:Biomarkers, Tumor