Finding and Characterizing Mammary Analogue Secretory Carcinoma of the Salivary Gland

Abstract

BackgroundA new tumor entity of the salivary glands, mammary analogue secretory carcinoma (MASC) with ETV6-NTRK3 translocation, has recently been proposed. MASC was originally diagnosed as adenocarcinoma, not otherwise specified (ANOS), or acinic cell carcinoma (AciCC) by the current World Health Organization classification. We aimed to identify MASC cases by molecular tests, and to characterize their clinical, histological, and immunohistochemical features.MethodsThirty cases of MASC candidates were selected after review of 196 salivary gland tumors, and subjected to break-apart ETV6 fluorescence in situ hybridization (FISH), and immunohistochemical study for S100 protein, gross cystic disease fluid protein 15, DOG1, estrogen receptor, and progesterone receptor.ResultsValid FISH results were obtained in 23 cases, and 13 positive cases were retrieved. MASCs were histologically varied, and the most frequent features observed in 10 cases were low-grade papillary/cystic/glandular patterns, intraluminal secretory materials, ovoid/wrinkled nuclei, and relatively abundant granular eosinophilic cytoplasms, corresponding to papillary-cystic or follicular types of AciCC. All cases showed diffuse immunopositivity for S100 protein. Three cases developed recurrences, but all patients remained alive.ConclusionsMASC could be a molecularly well-defined salivary gland neoplasm, encompassing some portions of AciCC and ANOS, but its histological spectrum and clinical implication require further investigation.

Cytogenetic and immunohistochemical characterization of mammary analogue secretory carcinoma of salivary glands

“…There have been 11 reported cases in patients under 18 years of age [6,13,26,[29][30][31][32][33][34][35][36]. One of our cases with rearranged ETV6 involved a 12-year-old female making this the youngest reported MASC in literature.…”

“…However, there was no significant difference between the two groups. Another study reported local recurrence in 3/9 cases after a median time of 44 months (range, 10-101) [31]. Out of the 172 MASC cases reported in the literature until early 2015, only seven patients died from disease.…”

Salivary Gland Tumor “Wishes” to Add to the Next WHO Tumor Classification: Sclerosing Polycystic Adenosis, Mammary Analogue Secretory Carcinoma, Cribriform Adenocarcinoma of the Tongue and Other Sites, and Mucinous Variant of Myoepithelioma

“…These tumors were termed mammary analogue secretory carcinomas (MASC). Since this initial report, there have been approximately 100 additional cases published [21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38][39][40]. These have been previously diagnosed as unusual variants of acinic cell carcinoma, adenoid cystic carcinoma, cystadenocarcinoma, mucoepidermoid carcinoma or adenocarcinoma, NOS.…”

“…The overall mortality is approximately 5 %; tumors that present with a higher stage are usually more aggressive and have a worse prognosis. Four cases have been associated with high-grade transformation [21,29]. These latter tumors are larger than typical MASC, reported up to 8 cm in greatest dimension.…”

Mammary analogue secretory carcinoma: A rare salivary gland tumour

“…Microscopically, the tumour is a circumscribed (but not encapsulated) multinodular mass divided by fibrous septa with microcystic, glandular and solid growth patterns. [4,8] Tumour cells are relatively uniform. [11] The tumour can invade within the salivary gland and can extend into the surrounding structures.…”