Plunging Ranula: A Case Report of a Rare Late Complication After Tongue Cancer Surgery.

A plunging ranula is a benign cystic lesion in the neck formed due to mucin extravasated from a salivary gland, most commonly the sublingual gland. Ranulas have been described in association with congenital anomalies, trauma, diseases of the sublingual gland, and HIV; however, rarely, they may result as a complication of various oral and neck surgeries. Here, we report a rare case of plunging ranula that developed in an elderly male as a sequalae to surgery for tongue cancer. The patient had undergone a partial glossectomy with supra-omohyoid neck dissection for tongue carcinoma and nine months later presented with cystic swelling on the floor of the mouth that was followed by neck swelling. It was treated successfully by excision, and the histopathology confirmed the diagnosis of ranula. We postulate that the tongue cancer surgery could have caused an inadvertent injury to the ducts of the sublingual salivary gland and mylohyoid muscle, leading to the development of a plunging ranula. Our case reiterates that surgeons need to be aware of the anatomy of the submandibular and submental region to avoid any surgical trauma to the sublingual and submandibular glands and their ducts along with the associated mylohyoid muscle.