A 13-year-old boy presented with a 4-year history of a slowly growing painless mass in the oral cavity. He had no history of oral bleeding or eating disorders. Oral examination revealed a firm, well-circumscribed, nontender tumor measuring approximately 2 cm in greatest dimension attached to the left anterior tonsillar pillar by a pedicle. There was no cervical lymph node enlargement.
Computed tomography of the neck with contrast revealed a subtle, moderately enhancing mass in the left dorsolateral aspect of the tongue (Figure 1, arrow). Wide excision of the tumor was performed with the patient under general anesthesia. The surgical margins were tumor free. Histologically, the tumor was composed of alveolarlike structures that were separated by thin, well-vascularized septa. Tumor cells were large, with round nuclei and granular cytoplasm. There was no mitotic figure or tumor necrosis (Figure 2). Intracytoplasmic diastase-resistant, periodic acid–Schiff (PAS)-positive crystalline material was identified in a few tumor cells (Figure 3). Immunohistochemically, the tumor cells were negative for cytokeratin, S-100 protein, HMB-45, and CD56. Diffusely positive nuclear staining of tumor cells for transcription factor 3 (TFE3) was found (Figure 4).
Chen H, Chen H, Chang Y, Liu C, Hsiao C. Pathology Quiz Case 1. Arch Otolaryngol Head Neck Surg. 2010;136(5):522. doi:10.1001/archoto.2010.45-a