title: Lysozyme Expression Can be Useful to Distinguish Mammary Analog Secretory Carcinoma from Acinic Cell Carcinoma of Salivary Glands.
abstract: Lysozyme is an enzymatic marker of acinar and intercalated duct cells of normal salivary glands. The aim of this study was to verify whether lysozyme expression could be useful to distinguish acinic cell carcinoma (ACC) from its main mimic, mammary analog secretory carcinoma (MASC). For comparison, DOG1 expression was analyzed as well. Seventeen cases of ACC, 15 MASC, and 125 other salivary tumors were studied. Lysozyme expression was found in tumor cells as well as in secreted material of MASC (86.6 % of cases) and in ductal cells of epithelial-myoepithelial carcinoma (EMC-53.8 %), pleomorphic adenoma (PA-29.1 %) and polymorphous low-grade adenocarcinoma (PLGA-23.8 %). However, in ACC, lysozyme was not expressed. Three patterns of DOG1 staining were seen: apical-luminal, cytoplasmic, and mixed cytoplasmic/membranous. The apical-luminal pattern was detected in ductal cells of ACC (58.8 % of cases), EMC (38.4 %), adenoid-cystic carcinoma (AdCC-35.3 %), PA (8.3 %), and PLGA (4.8 %). These tumors also showed mixed membranous/cytoplasmic staining for DOG1. MASC, mucoepidermoid, and salivary duct carcinomas exhibited only DOG1 cytoplasmic staining. In conclusion, lysozyme cannot be used as a marker of acinar differentiation in salivary tumors. However, lysozyme expression can be helpful to distinguish MASC from ACC due to its high frequency in the former and absence in ACC. It is likely that in MASC, lysozyme expression may reflect a lactational-like secretory differentiation since lysozyme belongs to breast milk proteins. Regarding DOG1 expression, the apical-luminal pattern is related to acinar and intercalated duct differentiation whereas the cytoplasmic staining does not seem to be associated with a specific cellular phenotype.
authors.affiliation: Department of Pathology, Medical Sciences Faculty, University of Campinas (UNICAMP), R. Tessália Vieira de Camargo, 126, Campinas, SP, 13083-887, Brazil.
authors.forename: Fernanda Viviane
authors.initials: FV
authors.lastname: Mariano
authors.affiliation: Department of Oral Pathology, Piracicaba Dental School, University of Campinas (UNICAMP), Piracicaba, SP, Brazil.
authors.forename: Camila Andrea Concha
authors.initials: CA
authors.lastname: Gómez
authors.affiliation: Department of Oral Pathology, Piracicaba Dental School, University of Campinas (UNICAMP), Piracicaba, SP, Brazil.
authors.forename: Juliana
authors.initials: J
authors.lastname: de Souza do Nascimento
authors.affiliation: Department of Oral Pathology, Piracicaba Dental School, University of Campinas (UNICAMP), Piracicaba, SP, Brazil.
authors.forename: Harim Tavares
authors.initials: HT
authors.lastname: Dos Santos
authors.affiliation: Department of Pathology, Medical Sciences Faculty, University of Campinas (UNICAMP), R. Tessália Vieira de Camargo, 126, Campinas, SP, 13083-887, Brazil.
authors.forename: Erika Said
authors.initials: ES
authors.lastname: Egal
authors.affiliation: Department of Oral Pathology, Sao Leopoldo Mandic Institute and Research Center, Campinas, SP, Brazil.
authors.forename: Victor Angelo Martins
authors.initials: VA
authors.lastname: Montalli
authors.affiliation: Department of Oral Pathology, Piracicaba Dental School, University of Campinas (UNICAMP), Piracicaba, SP, Brazil.
authors.forename: Pablo Agustin
authors.initials: PA
authors.lastname: Vargas
authors.affiliation: Department of Oral Pathology, Piracicaba Dental School, University of Campinas (UNICAMP), Piracicaba, SP, Brazil.
authors.forename: Oslei Paes
authors.initials: OP
authors.lastname: de Almeida
authors.affiliation: Department of Pathology, Medical Sciences Faculty, University of Campinas (UNICAMP), R. Tessália Vieira de Camargo, 126, Campinas, SP, 13083-887, Brazil. aaltemani@uol.com.br.
authors.forename: Albina
authors.initials: A
authors.lastname: Altemani
mesh_terms: D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000032:analysis*; D018267:Carcinoma, Acinar Cell / Q000175:diagnosis* / Q000201:enzymology; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D000069295:Mammary Analogue Secretory Carcinoma / Q000175:diagnosis* / Q000201:enzymology; D008875:Middle Aged; D009113:Muramidase / Q000032:analysis / Q000096:biosynthesis*; D012468:Salivary Gland Neoplasms / Q000175:diagnosis* / Q000201:enzymology; D055815:Young Adult
chemical_list: D014408:Biomarkers, Tumor; D009113:Muramidase
keywords: Acinic cell carcinoma; DOG1; Lysozyme; Mammary analog secretory carcinoma