Aims Salivary gland intraductal carcinoma (IDC) is a complex ductal neoplasm surrounded by a layer of myoepithelial cells. Recent insights have shown that there are three different types: intercalated duct‐like, with frequent NCOA4–RET fusions; apocrine, with salivary duct carcinoma‐like mutations; and mixed intercalated duct‐like/apocrine, with RET fusions, including TRIM27–RET. In addition, an oncocytic IDC has been described, but it remains unclear whether it represents a fourth variant or simply oncocytic metaplasia of another IDC type. Our aim was to more completely characterize oncocytic IDC. Methods and results Six IDCs with oncocytic changes were retrieved from the authors’ archives, from three men and three women ranging in age from 45 to 75 years (mean, 63 years). Five arose in the parotid gland, with one in an accessory parotid gland. Four patients with follow‐up were free of disease after 1–23 months. Several immunostains (S100, mammaglobin, androgen receptor, and p63/p40) and molecular tools (RNA sequencing, RET fluorescence in‐situ hybridisation, BRAF V600E VE1 immunohistochemistry, and Sanger sequencing) were applied. Histologically, the tumours were variably cystic with solid intracystic nodules often difficult to recognise as intraductal. In all, tumour ducts were positive for S100 and mammaglobin, negative for androgen receptor, and completely surrounded by myoepithelial cells positive for p63/p40. Molecular analysis revealed TRIM33–RET in two of six cases, NCOA4–RET in one of six cases, and BRAF V600E in two of six cases. One case had no identifiable alterations. Conclusions Oncocytic IDC shares similarities with intercalated duct‐like IDC. Although additional verification is needed, the oncocytic variant appears to be sufficiently unique to be now regarded as the fourth distinct subtype of IDC. Because of its indolent nature, oncocytic IDC should be distinguished from histological mimics.

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Lymphoepithelial carcinoma of salivary glands (LECSG) are rare neoplasms, reported in endemic populations (southeastern Chinese) with a strong Epstein-Barr virus (EBV) association. A retrospective series comparing EBV status within an ethnically diverse population (endemic vs. non-endemic patients) has not been reported. Sixteen LECSG were equally distributed between males (n = 8) and females (n = 8) with a median age of 54 years (range 18 to 85 years) at initial diagnosis. Ten patients were white, 4 Asian, and 2 black. The patients typically presented with swelling or mass for an average of 11.6 months. Tumors affected only major salivary glands: parotid (n = 13); submandibular (n = 3). Tumors were an average of 2.9 cm (range 1.5 to 5.8 cm). Nine of 16 (56%) patients had cervical lymph node metastases at presentation. No patients had nasopharyngeal or oropharyngeal tumors. Microscopically, the tumors were widely infiltrative, characterized by large polygonal to spindled cells arranged in a syncytial, lattice-like network in a background of lymphoplasmacytic cells. The neoplastic cells showed an open-vesicular nuclear chromatin to a more basaloid-morphology, the latter showing hyperchromatic nuclei and less cytoplasm, while nearly all of the cases had associated lymphoepithelial lesions/sialadenitis. By in situ hybridization, 8 of 16 cases had a strong, diffuse EBER expression (4 of 4 Asians; 4 of 12 non-Asians), while with immunohistochemistry all cases tested were pan-cytokeratin, CK5/6 and p63 reactive; none of the cases tested were p16 reactive. All patients were managed with wide or radical excision, 4 with concurrent chemoradiation, and 6 with radiation alone. Distant metastasis (lung, brain, and bone) developed in 2 patients. Overall follow-up (mean 3.8 years) revealed 12 patients alive and 2 dead, none with evidence of disease (mean 4.3 years); one white male alive with disease at 1.9 years, and one Asian female dead of disease at 4.2 years; both of these latter patients had Group IV stage disease. High stage (Group IV) patients had a shorter mean survival than lower stage patients: 3.1 versus 4.8 years, respectively. In conclusion, LECSG are uncommon primary neoplasms. Concurrent lymphoepithelial lesions may help suggest a primary tumor. The tumors, irrespective of race or ethnicity, may express EBER. There is an overall good survival, perhaps better for EBV-negative patients and for those with lower stage disease.