Extent of Surgery Affects Survival for Papillary Thyroid Cancer

In Brief Background: The extent of surgery for papillary thyroid cancers (PTC) remains controversial. Consensus guidelines have recommended total thyroidectomy for PTC ≥1 cm; however, no study has supported this recommendation based on a survival advantage. The objective of this study was to examine whether the extent of surgery affects outcomes for PTC and to determine whether a size threshold could be identified above which total thyroidectomy is associated with improved outcomes. Methods: From the National Cancer Data Base (1985–1998), 52,173 patients underwent surgery for PTC. Survival was estimated by the Kaplan-Meier method and compared using log-rank tests. Cox Proportional Hazards modeling stratified by tumor size was used to assess the impact of surgical extent on outcomes and to identify a tumor size threshold above which total thyroidectomy is associated with an improvement in recurrence and long-term survival rates. Results: Of the 52,173 patients, 43,227 (82.9%) underwent total thyroidectomy, and 8946 (17.1%) underwent lobectomy. For PTC <1 cm extent of surgery did not impact recurrence or survival (P = 0.24, P = 0.83). For tumors ≥1 cm, lobectomy resulted in higher risk of recurrence and death (P = 0.04, P = 0.009). To minimize the influence of larger tumors, 1 to 2 cm lesions were examined separately: lobectomy again resulted in a higher risk of recurrence and death (P = 0.04, P = 0.04). Conclusions: The results of this study demonstrate that total thyroidectomy results in lower recurrence rates and improved survival for PTC ≥1.0 cm compared with lobectomy. This is the first study to demonstrate that total thyroidectomy for PTC ≥1.0 cm improves outcomes. Extent of surgery for papillary thyroid cancers (PTC) remains controversial. The results of this study demonstrate that total thyroidectomy is associated with lower recurrence rates and improved survival for PTC ≥1.0 cm compared to lobectomy. This is the first study to demonstrate that total thyroidectomy for PTC ≥1.0 cm improves outcomes.