Oncocytic carcinoma of the thyroid: Conclusions from a 20‐year patient cohort

Abstract Background Oncocytic carcinoma (OCA) was recently reclassified as a distinct differentiated thyroid carcinoma (DTC). Given its rarity, OCA studies are limited. This study describes the characteristics of OCA in a 20‐year cohort. Methods Retrospective analysis of patients with OCA at a single tertiary care hospital from 2000 to 2021. Results Fifty‐one OCA patients (22M:29F) were identified. The mean age at diagnosis was 60.3 years; 90% presented as palpable mass; 24% had a family history of thyroid cancer. None had vocal fold paresis. On ultrasound, most tumors were solid and hypoechoic. FNA ( n = 14) showed Bethesda‐4 lesions in 93%. All were treated surgically. Histologically, 63% demonstrated angioinvasion, 35% had lymphovascular invasion, and 15% had extrathyroidal extension. Radioactive iodine was used as adjunct therapy in 77%. Conclusion OCA has distinct features that distinguish it from other DTCs, and additional focused studies will help clarify the aggressive nature, treatment options, and prognosis of the disease.