Low-grade cribriform cystadenocarcinoma of salivary glands: report of two cases and review of the literature

Low-grade cribriform cystadenocarcinoma (LGCCC) is a recently described rare tumor of salivary gland which exhibits clinically indolent behavior. This tumor predominantly consists of intraductal components and frequently exhibits papillary-cystic or cribriform proliferation pattern. Considering the histological features of LGCCC, it should be distinguished with papillocystic variant of acinic cell carcinoma, conventional salivary duct carcinoma, cystadenocarcinoma, polymorphous low-grade adenocarcinoma, carcinoma ex pleomorphic adenoma and mammary analogue secretory carcinoma. Herein, we presented two cases of LGCCC. One arose in the left parotid region in a 48-year-old male, and the other one arose in the right parotid gland in a 59-year-old female. For both cases, immunohistochemically, the luminal tumor cells showed diffuse expression of CK and S100; p63 and smooth muscle actin displayed a continuous rim of myoepithelial cells around all tumor islets; no myoepithelial cells were admixed with the luminal cells. Both patients were alive with no tumor recurrence or metastasis at follow-up. VIRTUAL SLIDES: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/2593621568999135.