Primary parotid lymphoepithelial carcinoma: A case report and literature review of a rare pathological entity

BACKGROUND: Lymphoepithelial carcinoma (LEC) of the salivary glands is a rare, but distinct, poorly-differentiated neoplasm that resembles undifferentiated nasopharyngeal carcinomas (NPC). Among primary salivary gland LECs, they most commonly arise in the parotid gland. These lesions have a noticeable racial predilection, mostly occurring in Asians and Arctic region native populations. They are strongly associated with Epstein-Barr virus (EBV), and are more common in EBV-endemic areas. The most common presenting symptoms of primary parotid LEC are parotid mass development and cervical lymphadenopathy. We report an unusual case of EBV-negative LEC in a Canadian Caucasian woman. CASE PRESENTATION: A 40-year-old female from Atlantic Canada presented with a rapidly enlarging preauricular mass and cervical lymphadenopathy. Preoperative diagnostics via radiology and fine needle aspiration alluded to an ambiguous primary parotid malignancy. She underwent a total parotidectomy with facial nerve sacrifice and ipsilateral selective neck dissection. The facial nerve was reconstructed with a lateral antecubital nerve graft. Pathology came back positive for LEC, and she began adjuvant radiotherapy. At her 1-year follow up, she was disease-free and obtained a House-Brackmann facial nerve function grade of 3. CONCLUSIONS: The case report highlights the importance of having a high index of suspicion and the need for interdisciplinary collaboration in reaching the diagnosis of primary parotid LEC. LEC can afflict patients of any ethnicity in non-EBV endemic areas and should therefore be considered in all patients with a painless parotid mass regardless of ethnicity. Further studies are required to elucidate the oncogenic role of EBV in these cancers.