The dynamic risk stratification (DRS) and its current definition of each response-to-therapy category in postlobectomy papillary thyroid carcinoma (PTC) patients have not been well studied. This study aimed to validate the DRS system and to investigate useful thyroglobulin (Tg) or anti-Tg antibody (Ab)-related parameters in defining each response-to-therapy category. This historical cohort study included 619 patients with PTC treated by thyroid lobectomy. All enrolled participants were stratified according to the American Thyroid Association (ATA) initial risk stratification system and DRS system, respectively. The association between these stratifications and structural recurrence was evaluated.