A comparison of thyroid cancer survival managed with different surgical subtypes: A SEER database analysis.

Abstract

e18110 Background: Thyroid cancer is a common endocrine malignancy that has been shown to be treatable with surgical intervention. Multiple surgical approaches can be used to treat thyroid cancer ranging from minimally-invasive local destruction or partial lobectomy to total thyroidectomy. There are limited studies comparing the survival between different surgical subtypes used to treat thyroid cancer at a national registry level; we herein investigate the differences between surgical subtypes in the management of thyroid cancer. Methods: We queried the Surveillance, Epidemiology, and End Results (SEER) Database for patients with thyroid cancer (primary site code C739) diagnosed between 2000-2019. All histologic subtypes were included. Patients with multiple primary tumors and patients without surgical intervention were excluded. Variables selected for review included age at diagnosis, race, sex, stage, and surgery subtype. Surgical subtypes of interest included codes 20-50 which corresponds to the removal of less than a lobe NOS, local surgical excision, partial lobectomy, lobectomy only, isthmectomy only, lobectomy with isthmectomy, removal of a lobe and partial removal of the contralateral lobe, subtotal or near-total thyroidectomy, and total thyroidectomy. Descriptive statistics, Kaplan-Meier (KM), and Cox regression analyses were performed using SPSS version 28. Results: A total of 167932 patients were included. Of these, 1564 patients received local/partial lobectomy. On KM, partial lobectomy showed significantly improved survival compared to both local excision and removal of less than a lobe, NOS (p’s < 0.05). For lobectomies and isthmectomies, a total of 24904 patients were included. On KM, both lobectomy alone and lobectomy with isthmectomy showed survived significantly improved than isthmectomy alone (p’s < 0.001). A total of 141464 patients received either subtotal thyroidectomies or total thyroidectomies, 95% of which were total thyroidectomies. On KM, patients managed with total thyroidectomy survived significantly better than subtotal thyroidectomy (p < 0.001). After controlling for age, sex, race, and stage, Cox regression analysis showed complete lobectomy (Hazard ratio [HR] = 0.352), subtotal thyroidectomy (HR = 0.416), and total thyroidectomy (HR = 0.162) all had significantly improved survival relative to local excision or destruction (p’s < 0.001). Conclusions: Our results show that more complete removal of the thyroid, including complete lobectomy, subtotal thyroidectomy, and total thyroidectomy, is associated with improved survival in patients with thyroid cancers. The improved outcomes with more invasive procedures suggest wider margins may reduce the risk of spread or recurrence after initial resection.