Purpose: Active surveillance (AS) has been gaining attention as an option for papillary thyroid microcarcinoma (PTMC) management in selected patients. However, some questions remain on PTMC behavior, particularly on tumor multicentricity and cervical metastases. Our aim is to gather insights on the natural history of PTMC on patients treated with thyroidectomy.Methods: Consecutive patients diagnosed with PTMC (tumor size ≤ 1.0 cm) had their clinical characteristics, interventions, and outcomes

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... escribed. Patients were classified as incidental or nonincidental based on the diagnosis of PTMC after or before surgery, respectively. Results: A cohort of 257 patients was included for this study, 84.0% of which were women, and the mean age was of 48.3 ± 13.5 years. The mean tumor size was of 0.68 ± 0.26 cm, 30.4% were multifocal, 24.5% had cervical metastasis, and 0.4% distant metastasis. The nonincidental and incidental tumors differed in tumor size (0.72 ± 0.24 and 0.60 ± 0.28 cm, respectively, p=0.003) and in presence of cervical metastasis (31.3% and 11.9%, respectively, p<0.001). Male sex, nonincidental diagnosis, and younger age were independent predictors of cervical metastasis. Notably, each year less in age represented an increase of 3% in likelihood of nodal metastasis (p<0.001). After 5.5 years (P25-75 2.5-9.7) of follow-up, only 3.8% of patients had persistent structural disease (3.4% cervical). Predictors of persistent disease at multivariate analysis included cervical metastasis and multicentricity.Conclusion: Incidental and nonincidental PTMC patients displayed excellent outcomes. Cervical metastasis and multicentricity are frequent findings in PTMC and prognostic factors for persistent disease.