(Kiosk 1) A Unique Presentation of First Bite Syndrome in a Patient with Follicular Lymphoma

Case Diagnosis: 59-year-old male with past medical history of follicular lymphoma (FL) presenting with bilateral constant jaw pain, worse with chewing, concerning for an atypical presentation of first bite syndrome (FBS).

Case Description or Program Description: After diagnosis of FL, the patient was started on immunotherapy, successfully completing three cycles. He spontaneously developed pain in the bilateral parotid region. Initially associated with chewing, his pain later progressed to sharp pain while eating, as well as a post-prandial electric sensation radiating to bilateral maxillary & mandibular regions. Relevant imaging including CT neck, PET scan of head and neck, and MR of oral cavity did not reveal pertinent findings correlating to an etiology of his symptoms.

Setting: Patient received treatment in an ambulatory setting of a tertiary care cancer hospital.

Assessment/Results: The patient underwent conservative management for presumed FBS vs trigeminal neuralgia with pharmacologic treatments including oral steroids, NSAIDs, gabapentin, and pregabalin without relief. Over the course of a month, he underwent interventions including sphenopalatine ganglion nerve block via atomizer, botulinum toxin injections to bilateral parotids, and bilateral fluoroscopic-guided trigeminal nerve (V2) blocks with the latter providing mild to moderate relief of symptoms.

Discussion (relevance): The etiology of FBS is thought to be related to damage to the cervical sympathetic trunk leading to loss of sympathetic innervations to the parotid salivary gland, usually in the setting of head and neck surgery. There are, however, also case reports of idiopathic FBS for those without history of head and neck surgery or malignancy. In these cases the pathophysiology is unknown. While pain may resolve spontaneously in some patients, there are cases that require a more comprehensive approach as demonstrated in this case.

Conclusions: FBS can be a debilitating diagnosis for patients, affecting quality of life and activities of daily living. Understanding atypical presentations and treatment options is important to optimize symptom management.