Adenoid cystic carcinoma of palatine tonsil: A case report.

In head and neck, adenoid cystic carcinoma (ACC) is a rare malignant tumor. ACC mainly generated from minor salivary glands, especially in the palate. We report an extremely rare case of ACC generating in the left palatine tonsil. A 50-year-old woman with foreign body sensation in the pharynx for 6-month was admitted to our hospital. Physical examination revealed a dark red mass in the soft palate near the upper pole of the left tonsil. Preoperative imaging examinations indicated a low-density mass in the left tonsillar area on the CT plain scan, which was a hyperintense mass at the anterior superior pole of the left tonsil on T2-weighted MRI. Complete surgical resection of the mass together with the left palatine tonsil was conducted under general anesthesia. The diagnosis of ACC was established based on histopathology and immunohistochemistry results. Then, postoperative radiotherapy of 60 Gy was administered. During regular medical follow-up for 12 months, no local recurrence was observed. Complete surgical resection, with or without postoperative radiotherapy is generally acknowledged as the standard of care for ACC. Despite the extremely low incidence in palatine tonsil, clinicians should consider the differential diagnosis of ACC.