A previously healthy man in his 20s who was of Asian heritage presented with a nontender mass in the left parotid region, which had been slowly enlarging for 18 months. He had experienced occasional blepharospasm and paresthesia in the ipsilateral eye and cheek. He had also noted an unintended 3-kg weight loss in the same duration, which he subjectively attributed to the stress of school. Physical examination demonstrated a firm, immobile, irregular mass n the left parotid and approximately 3 × 3 cm in size. Mild left-sided buccal weakness was noted. Otherwise, his cranial nerve function was intact. Fine needle aspiration demonstrated medium-size ovoid cells with minimal cytoplasm in crowded groups. T2-weighted magnet resonance imaging following the initial computed tomographic (CT) scan demonstrated a poorly marginated mass that was 4 cm in maximum diameter abutting the left superficial parotid with involvement of the masseter (Figure, A). A parotidectomy with excision of the tumor was planned. During the initial exposure of the tumor, an intraoperative frozen section demonstrated a cellular infiltrate, and a diagnosis of lymphoma could not be excluded. Given the size and fixed nature of the tumor, the decision was made to stop resection on establishing a definitive diagnosis. Flow cytometry demonstrated phenotypically normal T-cell and B-cell populations. Permanent histologic sections demonstrated nests of nonkeratinizing undifferentiated atypical epithelial cells intimately intermingled with a dense lymphoplasmacytic infiltrate (Figure, B). Immunohistochemical analysis for cytokeratin AE1/3 was positive in the carcinoma cells (Figure, C). In situ hybridization for Epstein-Barr virus–encoded small RNAs (EBERs) was positive (Figure, D).
Ran C, Tafe LJ, Paydarfar JA. Nontender Parotid Mass in a Young Asian Man. JAMA Otolaryngol Head Neck Surg. 2015;141(8):763-764. doi:10.1001/jamaoto.2015.0956