Active surveillance vs. surgery in low-risk papillary thyroid microcarcinoma patients and the risk of loss to follow-up.

ABSTRACT

BACKGROUND: Papillary thyroid microcarcinoma (PTMC) management has evolved, with active surveillance (AS) gaining prominence as a management option. However, a key concern for both clinicians and patients is the potential for patient loss to follow-up during AS. AIMS: This study aimed to determine adherence and loss-to-follow-up rates in low-risk PTMC patients undergoing AS versus surgical intervention, in order to gain insights into clinical pathways and safety profiles. MATERIALS AND METHODS: This cohort study analyzed the 2016 data from a single registered institution of Japan's public National Cancer Registry. RESULTS: We identified and retrospectively analyzed the cases of 327 patients diagnosed with low-risk PTMC; 227 patients chose to undergo AS while the other 100 underwent PTMC surgery. Main outcomes were the adherence rate and loss-to-follow-up rate of each group, factors influencing discontinuation, and safety considerations. The rate of AS adoption was substantial in the complete series of 327 low-risk PTMC patients (69.4%). There was a significantly higher loss-to-follow-up rate at 5 years in the AS group (28.6%) compared to the Surgery group (17.8%) (HR 1.62, 95% CI 1.01-2.61; p = 0.046). Both univariate and multivariate analyses confirmed the significantly higher loss-to-follow-up rate in the AS group as well as in older patients. No deaths due to PTMC progression were observed in the cases lost to follow-up. CONCLUSION: Despite concerns about loss to follow-up, active surveillance remains a safe option for low-risk PTMCs. Consistent follow-up strategies are crucial, and further research is needed to enhance patient counseling and care for the management of patients with PTMC.