Is Less More? Adoption of Treatment Guidelines for Low-Risk Papillary Thyroid Cancer

Abstract

The debate over the appropriate extent of surgery for low-risk papillary thyroid cancer (PTC) has been ongoing for years. Early data studying long-term outcomes in patients with PTC established total thyroidectomy as the treatment of choice to reduce the risk of recurrence and improve overall survival. However, in understanding that the majority of thyroid surgery in the USA is performed by low-volume surgeons, the first set of guidelines released by the American Thyroid Association (ATA) in 1996 deemed the optimal extent of surgery to be controversial; total thyroidectomy may result in decreased recurrence and allows for radioactive iodine treatment (RAI) and use of thyroglobulin for surveillance, but there is a risk of increased complication rates for those less experienced surgeons. Later, population-level data showing improved recurrence rates and overall survival in low-risk patients undergoing total thyroidectomy resulted in a recommendation in the 2009 ATA guidelines for total thyroidectomy for all patients with PTC larger than 1 cm. In November 2015, an updated set of guidelines were released by the ATA. The greatest shift from previous recommendations was that, for patients with intrathyroidal tumors between 1 and 4 cm and without other high-risk features, either total thyroidectomy or thyroid lobectomy could be performed. This shift was largely based on data showing no difference in overall survival for patients with tumors who fit these criteria when treated with either thyroid lobectomy or total thyroidectomy when adjusted for comorbidities and aggressive pathologic features, as well as an understanding that recurrences in patients undergoing lobectomy were salvageable without any negative impact on overall survival. Furthermore, they again noted that over 80% of thyroid resections are performed by low-volume surgeons, who may have higher complication rates after total thyroidectomy. All of this, in addition to the decreased utilization of RAI treatment for low-risk PTC, presents a strong case for consideration of thyroid lobectomy in appropriately selected patients. Early responses to the guidelines expressed concerns about preoperative selection of patients for thyroid lobectomy and that many characteristics that would necessitate total thyroidectomy or RAI would only be evident on final pathology. These studies suggested that completion thyroidectomy would be necessary in 19–43% of patients to facilitate appropriate treatment. Despite these data, several studies have shown an increase in the use of thyroid lobectomy as sole treatment for patients with thyroid cancer. Ullmann et al. examined the National Surgical Quality Improvement Program (NSQIP) database between 2009 and 2017 and found an increase in the use of thyroid lobectomy for patients with thyroid cancer from 17.3% before 2015 to 22.0% after release of the guidelines without a concomitant increase in completion thyroidectomies. Recently, Toumi et al. examined IBM MarketScan data, which showed a similar increase in use of thyroid lobectomy from 17% of all thyroid cancers to 28% by the end of 2018 that was also associated with release of the 2015 ATA guidelines. Single-institutional studies have also shown increasing rates of thyroid lobectomy for thyroid cancer with declining completion thyroidectomies. Society of Surgical Oncology 2021