Nodal Metastases in Oncocytic Carcinoma of the Thyroid Are Associated With Decreased Survival

Oncocytic thyroid carcinoma (OCA) carries a worse prognosis when compared to papillary or follicular thyroid cancer; however, the degree to which OCA is associated with nodal metastases is poorly understood. We sought to determine the predictors of survival in patients with OCA who underwent nodal evaluation.

The National Cancer Database was queried from 2004 to 2020 for patients with OCA who underwent nodal evaluation. Patients who underwent regional lymph node evaluation were included in the analysis. Patient demographics, tumor characteristics, surgical management, and survival were analyzed. Kaplan-Meier and Cox proportional hazards models were used to determine overall survival (OS) rates and estimate the association between nodal disease and survival.

There were 12,438 patients with OCA. A total of 3373 patients (27.1%) underwent nodal evaluation, of which 462 (14%) were found to have pathologic nodal metastases. Patients with nodal metastases were more likely to be older, male, Hispanic, treated at an academic facility, have public insurance, have longer median distance to treatment facility and have a larger tumor size, lymphovascular invasion, and positive margins (P < 0.01). Of the patients who underwent surgery, those with nodal metastases had shorter 1-y, 3-y, and 5-y OS. Nodal metastasis is independently associated with worse OS (hazard ratio: 2.7 [95% confidence interval: 2.12, 3.39], P < 0.0001).

Nodal metastases were found in 14% of patients with OCA who underwent nodal evaluation and were associated with compromised survival. Identifying patients with increased risk of nodal metastases in patients with a high index of suspicion for OCA will help with surgical decision-making.