We present a series of 16 salivary gland tumors with histomorphologic and immunohistochemical features reminiscent of secretory carcinoma of the breast. This is a hitherto undescribed and distinctive salivary gland neoplasm, with features resembling both salivary acinic cell carcinoma (AciCC) and low-grade cystadenocarcinoma, and displaying strong similarities to breast secretory carcinoma. Microscopically, the tumors have a lobulated growth pattern and are composed of microcystic and glandular spaces with abundant eosinophilic homogenous or bubbly secretory material positive for periodic acid-Schiff, mucicarmine, MUC1, MUC4, and mammaglobin. The neoplasms also show strong vimentin, S-100 protein, and STAT5a positivity. For this tumor, we propose a designation mammary analogue secretory carcinoma of salivary glands (MASC). The 16 patients comprised 9 men and 7 women, with a mean age of 46 years (range 21 to 75). Thirteen cases occurred in the parotid gland, and one each in the minor salivary glands of the buccal mucosa, upper lip, and palate. The mean size of the tumors was 2.1 cm (range 0.7 to 5.5 cm). The duration of symptoms was recorded in 11 cases and ranged from 2 months to 30 years. Clinical follow-up was available in 13 cases, and ranged from 3 months to 10 years. Four patients suffered local recurrences. Two patients died, 1 of them owing to multiple local recurrences with extension to the temporal bone, and another owing to metastatic dissemination to cervical lymph nodes, pleura, pericardium, and lungs. We have shown a t(12;15) (p13;q25) ETV6-NTRK3 translocation in all but one case of MASC suitable for analysis. One case was not analyzable and another was not available for testing. This translocation was not found in any conventional salivary AciCC (12 cases), nor in other tumor types including pleomorphic adenoma (1 case) and low-grade cribriform cystadenocarcinoma (1 case), whereas ETV6-NTRK3 gene rearrangements were proven in all 3 tested cases of mammary secretory carcinoma. Thus, our results strongly support the concept that MASC and AciCC are different entities.

Department of Pathology Charles University Pilsen Czech Republic

Comment In

Am J Surg Pathol. 2011 Oct;35(10):1600-2. doi: 10.1097/PAS.0b013e31822832c7. PubMed

References provided by Crossref.org

Discovery of Novel TULP4/ACTN4/EWSR1/ACTB::MYB and ESRRG::DNM3 Fusions Expands Molecular Landscape of Adenoid Cystic Carcinoma Beyond Fusions Between MYB/MYBL1 and NFIB Genes

Molecular pathology in diagnosis and prognostication of head and neck tumors

High-grade non-intestinal type sinonasal adenocarcinoma with ETV6::NTRK3 fusion, distinct from secretory carcinoma by immunoprofile and morphology

Development of head and neck pathology in Europe

SalvGlandDx - a comprehensive salivary gland neoplasm specific next generation sequencing panel to facilitate diagnosis and identify therapeutic targets

ALK alterations in salivary gland carcinomas

(Mammary Analogue) Secretory Carcinoma of the Nasal Cavity: Report of a Rare Case with p63 and DOG1 Expression and Uncommon Exon 4-Exon 14 ETV6-NTRK3 Fusion Diagnosed with Next Generation Sequencing

Colonic Adenocarcinomas Harboring NTRK Fusion Genes: A Clinicopathologic and Molecular Genetic Study of 16 Cases and Review of the Literature

MicroRNA dysregulation in adenoid cystic carcinoma of the salivary gland in relation to prognosis and gene fusion status: a cohort study

Recurrent EML4-NTRK3 fusions in infantile fibrosarcoma and congenital mesoblastic nephroma suggest a revised testing strategy

Newly described salivary gland tumors

Salivary acinic cell carcinoma: reappraisal and update

Primary pulmonary clear cell sarcoma-the first two reported cases

Mammary analogue secretory carcinoma of salivary gland origin: an update and expanded morphologic and immunohistochemical spectrum of recently described entity