Mammary Analogue Secretory Carcinoma of Salivary Gland – A Diagnostic Dilemma

Mammary Analogue Secretory Carcinoma (MASC) of salivary gland is a recently described entity with unique morphologic, clinical and genetic characteristics, including the characteristic t(12;15)(p13;q25) with ETV6-NTRK3 translocation found in secretory carcinomas of the breast. Before their initial description, these salivary gland tumours were generally diagnosed as acinic cell carcinoma or adenocarcinoma. We present a case of 32-year-old, male presenting with painless swelling over left cheek which was gradually increasing in size. The histopathological examination of the lesion was done and two possible differential diagnosis were acinic cell carcinoma (papillary cystic variant) and MASC of the parotid gland. Immunohistochemistry was performed which demonstrated combined positivity for S-100, mammglobin, CK-7 and DOG-1 negativity which confirmed the diagnosis of MASC of parotid.