Ancient schwannoma in the sublingual space masquerading as a plunging ranula

Ancient schwannomas are benign, slow-growing tumours derived from the neural sheath. They are characterized by degenerative changes which are not seen in the common schwannoma. An unusual case of ancient schwannoma of the sublingual space is reported to highlight the diagnostic challenge that this tumour presents. A 49-year-old male patient presented with an 8-month history of a right-sided neck swelling, palpable in the anterior part of the submandibular triangle. Pre-operative imaging showed a non-enhancing mass in the sublingual space spilling into the submandibular triangle, consistent with a plunging ranula. Fine needle aspiration cytology was inconclusive. However, histopathology of the lesion confirmed the diagnosis of an ancient schwannoma, which is seldom found in the sublingual space.