Salivary glands may give rise to a wide spectrum of different tumors. This review concentrates on 4 salivary gland tumors that have been accepted in the recent literature as new neoplastic entities: mammary analog secretory carcinoma, cribriform adenocarcinoma of minor salivary glands (CASG), sclerosing polycystic adenosis/adenoma (SPA), and the mucinous/secretory variant of myoepithelioma. Mammary analog secretory carcinoma is a distinctive low-grade malignant salivary cancer that harbors a characteristic chromosomal translocation, t(12;15) (p13;q25), resulting in an ETV6-NTRK3 fusion. Cribriform adenocarcinoma (CASG) is a distinct tumor entity that differs from polymorphous low-grade adenocarcinoma by location (ie, most often arising on the tongue), by prominent nuclear clearing, differing alterations of the PRKD gene family, and clinical behavior with frequent metastases at the time of presentation of the primary tumor. Early nodal metastatic disease is seen in most cases of CASG; yet, they are still associated with indolent clinical behavior, making it a unique neoplasm among all low-grade salivary gland tumors. SPA is a rare sclerosing tumor of the salivary glands characterized by the combination of cystic ductal structures with variable cell lining including vacuolated, apocrine, mucinous, squamous, and foamy cells, by prominent large acinar cells with coarse eosinophilic cytoplasmic zymogen-like granules, and by closely packed ductal structures, surrounded by a peripheral myoepithelial layer and stromal fibrosis with focal inflammatory infiltrates. SPA frequently harbors intraductal epithelial dysplastic proliferations ranging from mild dysplasia to severe dysplasia/carcinoma in situ. Moreover, SPA has been proven to be a clonal process by HUMARA assay and is associated with considerable risk of recurrence. Therefore, on the basis of all these newly recognized findings, we believe that SPA is likely a neoplasm, and we suggest the name “sclerosing polycystic adenoma.” The mucinous variant of myoepithelioma is a myoepithelial tumor with foci of prominent cytoplasmic clearing frequently containing intracellular mucin material and having signet-ring morphology.
*Department of Pathology, Charles University, Faculty of Medicine in Plzen, Plzen, Czech Republic
†Department of Pathology, Providence, RI and Fall River, MA
Departments of ‡Pathology, Microbiology, and Immunology
§Otolaryngology, Vanderbilt University Medical Center, Nashville, TN
∥Department of Pathology, University of Arkansas for Medical Sciences, Little Rock, AR
¶Department of Pathology, The Johns Hopkins Medical Institutions, Baltimore, MD
#Department of Biomedical Sciences and Medicine, University of Algarve, Faro, Portugal
**University of Udine School of Medicine, Udine, Italy
††Department of Otorhinolaryngology-Head and Neck Surgery, University Hospitals Leuven
‡‡Department of Oncology, Section Head and Neck Oncology, KU Leuven, Leuven, Belgium
§§International Head and Neck Scientific Group, Padua, Italy
This article was written by members of the International Head and Neck Scientific Group (http://www.IHNSG.com).
Conflicts of Interest and Source of Funding: The authors have disclosed that they have no significant relationships with, or financial interest in, any commercial companies pertaining to this article.
Correspondence: Alena Skálová, MD, PhD, Sikl’s Department of Pathology, Medical Faculty of Charles University, Faculty Hospital, E. Benese 13, 305 99 Plzen, Czech Republic (e-mail: firstname.lastname@example.org).