Active Surveillance a Safe, Viable Option in Papillary Thyroid Cancer

Active surveillance (AS) appears to be a durable and safe long-term management strategy for patients with small, low-risk papillary thyroid cancer (PTC), with durability and age strongly correlated, according to a long-term cohort study (NCT03271892) published in JAMA Surgery.^1,2

The key takeaway from the study was that the likelihood of continuing with AS was significantly higher in older patients. The 5-year rate of continuing AS was 94.9% for patients aged 65 or older, compared with 79.1% for those aged 45 to 64 and 58.5% for patients younger than 45.

Another key finding was that younger patients were significantly more likely to cross over from AS to active treatment (eg, surgery). The 5-year cumulative crossover rate was 41.5% (95% CI, 25.6%–56.8%) for patients under 45, but only 5.1% (95% CI, 0.9–15.2%) for those 65 and older (P<.001). The higher crossover rate in younger patients was largely driven by patient preference rather than disease progression. While rates of progression did not significantly vary by age, 23% of patients under 45 who chose AS eventually opted for surgery by choice compared with 0% of patients aged 65 and older.

Over a median follow-up of 71 months, there were no thyroid cancer-related deaths or instances of distant metastatic disease among any of the 200 patients, regardless of whether they chose AS or immediate surgery. Additionally, for patients who eventually underwent surgery after a period of AS, the extent of surgery, use of radioactive iodine treatment, and rates of complications were not significantly different from those who chose immediate surgery. Most treated patients in both groups were disease-free at their last follow-up.

The findings support offering AS as a first-line management option for patients with small, low-risk PTC. This choice is particularly relevant for older patients, who may wish to avoid the heightened risks associated with thyroidectomy.

“Our data compare favorably relative to other cohort studies examining AS outcomes in patients with small, low-risk PTC where investigators have included some patients with tumors larger than 1 cm in maximal diameter, particularly considering differences in study design and follow-up duration. Thus, there is growing evidence on the safety and efficacy of AS for small, low-risk PTC, even beyond microcarcinomas,” wrote Anna M. Sawka, MD, PhD, et al.

How Was the Study Designed?

This analysis was based on a single-center, prospective, long-term follow-up cohort study conducted at a tertiary care hospital in Toronto, Canada. The study aimed to evaluate the durability of active surveillance in patients with small, low-risk PTC according to their age at enrollment.

The study enrolled 200 adult patients with localized, low-risk PTC measuring less than 2 cm. Patients were offered the choice between AS or immediate thyroid surgery. Data were collected between May 2016 and February 2021, with a final analysis cutoff of May 25, 2025. The median follow-up for the entire cohort was 71 months. The overall study population consisted of 153 female patients (76.5%) and 47 male patients (23.5%), with a mean age of 52.0 years.

The authors acknowledged several limitations that should be considered when interpreting these findings. Firstly, the study was not randomized, which may have introduced selection bias. Next, data were collected at a single Canadian tertiary care center, which may limit the generalizability of the findings. Some subgroup comparisons were limited by small sample sizes. Statistical analyses were not corrected for multiple testing, which could increase the risk of type I error. Finally, the post-hoc exploratory analysis performed to identify an optimal age cutoff should be considered hypothesis-generating, rather than conclusive evidence.

The data underscore the value of shared, patient-centered decision-making, allowing individuals to select a management path that aligns with their personal preferences and risk tolerance. The excellent oncologic outcomes, even among those who later required surgery, support the safety of an initial AS approach.

REFERENCES:

1. Sawka AM, Ghai S, Rotstein L, et al. Long-Term Durability of Active Surveillance of Small, Low-Risk Papillary Thyroid Cancer. JAMA Surg. Published online August 20, 2025. doi:10.1001/jamasurg.2025.2957.

2. Deciding on Active Surveillance or Surgery for Primary Management of Low Risk Papillary Thyroid Cancer (AS-PTC). ClinicalTrials.gov. Updated October 8, 2024. Accessed October 7, 2025. https://www.clinicaltrials.gov/study/NCT03271892