Tonsillar solitary fibrous tumour: A interesting rare case.

A solitary fibrous tumour (SFT) is a rare mesenchymal tumour that frequently originates in the mesothelium-covered surfaces, such as the pleura and peritoneum. It may develop in various body parts, including the head and neck. These tumours may arise in several different patterns, which results in difficulties in diagnosing them. This case is a solitary tumour developing from the palatine tonsil in a 17-year-old male patient; it is the second case in the literature. The tumour has the histopathological characteristics of a patternless pattern, a slight pleomorphism, and a composition of hypercellular and hypocellular sites. Immunohistochemically, the tumour cells showed a strong positive staining with CD34, Bcl-2, and vimentin. No recurrence developed in the patient's approximately 18-month-long follow-up period.