(0410) Management of Incidentally Diagnosed Regionally Metastatic Thyroid Cancer in Patients With Other Primary Head and Neck Cancer

Introduction: Thyroid cancer (TC) is a common malignancy in adult patients and can be an incidental finding on routine imaging or in the setting of other cancer workups. Though the American Thyroid Association (ATA) has guidelines for the treatment of differentiated thyroid carcinoma, there are no specific recommendations addressing the management of incidentally discovered TC on surgical pathology after other head and neck (H&N) surgery. Our objective is to report on the prevalence of incidental regionally metastatic TC in patients undergoing elective or therapeutic neck dissection for another primary H&N carcinoma and report on their management strategies at a large urban tertiary care center.

Methods: This was a retrospective chart review of patients with a diagnosis of H&N cancer who underwent a neck dissection at a single tertiary care institution between January 2013 and January 2023.

Results: Of 2,169 patients with a diagnosis of H&N cancer, 7 were found to have an incidental metastatic TC (0.32%). Mean age at surgery was 68.9 ± 12 years in a predominantly male cohort (n = 6, 86%). All primary H&N cancers were squamous cell carcinomas, and all TC was papillary type. Postoperatively, 5 patients (n = 5, 71%) received adjuvant radiation and three patients (n=3, 43%) received immunotherapy. Two patients received additional total thyroidectomy for their incidental TC (n = 2, 29%), with an average time to additional surgery of 35 days. Postoperatively, 5 patients (n = 5, 71%) were recommended to have surveillance imaging for their TC, with only two completing imaging (n = 2, 40%). No patients were noted to have disease progression of their TC.

Conclusions: Incidental regionally metastatic thyroid cancer in patients with another primary head and neck carcinoma is rare, and clinical guidelines are not clearly defined. Despite a low n, our results may be important in guiding clinical management of incidental metastatic thyroid carcinoma in the setting of a primary head and neck malignancy. Future studies are indicated to guide clinical decision-making.