Skull Base Squamous Cell Carcinoma Presenting as Collet-Sicard Syndrome: A Rare Cause of Multicranial Nerve Dysfunction.

The lower cranial nerves (CNs) - IX, X, XI, and XII - are affected by lesions of the skull base that impact the hypoglossal canal and jugular foramen in Collet-Sicard Syndrome (CSS), a rare disorder. Loss of posterior tongue taste sensation (IX nerve), paralysis of the vocal cords and difficulty swallowing (resulting from the X nerve), weakness in the sternocleidomastoid and trapezius muscles (due to the XI nerve), and atrophy and weakness of the tongue muscles (caused by the XII nerve) are all signs of this condition. The purpose of this report is to describe a case of squamous cell carcinoma (SCC), presenting features of multiple CN palsies. We report a 61-year-old gentleman presenting with hoarseness of voice, whispering speech, gradually progressive difficulty in swallowing both solids and liquids, associated with nasal regurgitation of food, difficulty in formation of food bolus, and weakness of the right shoulder for six months. Neurological examination showed a left-deviated uvula, absent gag reflex on the right side, atrophied and weak right sternocleidomastoid muscle, weaker right-sided shrug, drooping of the right shoulder, and atrophy of the right side of the tongue, which was deviated towards the right. Contrast-enhanced computed tomography (CECT) of the head and neck showed heterogeneously enhancing lesions in the region of the right vallecula and base of the tongue, extending medially to cross the midline and involving the opposite vallecula, a few enlarged, heterogeneously enhancing, necrotic right cervical lymph nodes, and an abutting right submandibular gland completely encasing the carotid sheath (CS) and narrowing its contents. A biopsy of the lesion revealed well-differentiated SCC. Management involved surgical resection of the lesion and concurrent chemoradiation. The patient had symptomatic relief from her symptoms and was able to swallow liquids without any difficulty at a two-month follow-up. We emphasize that skull base lesions like SCC should be considered in the differential diagnoses of patients presenting with CNs IX-XII palsies. This also highlights the importance of multidisciplinary care in patients with multiple CN palsies.