Impact of the 2015 American thyroid association guidelines on treatment in older adults with low-risk, differentiated thyroid cancer

Background: The impact of the 2015 ATA guidelines on treatment for differentiated thyroid cancer (DTC) in older adults is unclear. Methods: 60,567 adults (age≥18) with low-risk DTC diagnosed between 2010 and 2018 were identified using SEER-21. Annual rates of total thyroidectomy (TT), hemithyroidectomy (HT), and active surveillance (AS) were analyzed using interrupted time series stratified by age: younger adults (18–64), older adults (65–79), and the super-elderly (≥80). Results: After 2015, annual rates of TT decreased by 2.6% and 1.9% in younger and older adults (p < 0.001), but increased by 4.6% in the super-elderly (p = 0.0126). Annual rates of HT increased by 2.6% and 1.7% in younger and older adults (p < 0.001), but decreased by 3.8% in the super-elderly (p = 0.0029). Older adults and the super-elderly were more likely than younger adults to undergo HT (aOR = 1.1, 95% CI: 1.03–1.2, p = 0.002 and aOR = 1.5, 95% CI: 1.3–1.7, p < 0.001) and AS (aOR = 1.5, 95% CI: 1.4–1.7, p < 0.001 and aOR = 6.5, 95% CI: 5.4–7.7, p < 0.001) when compared to TT following 2015. Conclusions: Treatment of DTC continues to vary significantly among age groups.