RESUMEN
Objective:To evaluate the feasibility, safety and effectiveness of the active surveillance as an alternative to surgery in patients with low-risk papillary thyroid microcarcinoma(PTMC); And to explore potential surgical indicators based on characteristics of patients and medical environment.Methods:A prospective cohort study was conducted in patients with low risk PTMC and received active surveillance management( n=98). Patient adherence, non-progression surgery rates were described, cumulative incidence of tumor growth≥3 mm and tumor volume increase≥50% under ultrasonic monitoring, as well as tumor doubling rate(TDR) were evaluated. Results:A total of 98 patients were enrolled in this prospective cohort. The median age was 39(30, 45) years, and the median baseline diameter of the index tumors was 5.0(3.8, 6.8) mm, with 63.3% of tumors being≤5 mm. After a median 22(12, 44) months follow-up, tumor size growth≥3 mm and tumor volume increase≥50% occurred in 11(11.2%) and 50(51.0%) patients, and no new lymph node metastasis, distant metastasis, and death occurred. Five cases(5.1%) required delayed surgery, and other five non-progression patients opted in surgery based on their own preferences. One patient lost to follow-up. The median post-tumor progression TDRs was significantly lower than that of pre-tumor progression TDRs [size growth per year: -0.09(-0.12, 0.48) vs 0.91(0.86, 1.25), P=0.014, n=8; volume increase per year: 0.29(-0.14, 0.70) vs 1.04(0.66, 2.17), P<0.001, n=39]. After tumor size and volume progression, 62.5% and 43.6% of tumors were remained stable or shrank, respectively. Conclusions:Actived surveillance can be considered as one of the management strategies for low-risk PTMC. Given the differences in population and clinical characteristics, it should be taken in to consideration in developing active surveillance management, such as candidate criteria, follow-up strategies, and intervention indications.