[Active surveillance for thyroid micro-malignant nodules].

Objective: To evaluate the effect of ultrasound diagnosis of thyroid micro-malignant nodules and accumulate practical experience for the management of active surveillance for them, so as to avoid overtreatment. Methods: A total of 949 patients who were diagnosed with thyroid malignant nodules using ultrasonography, with the nodules being less than 1 cm in size and without regional lymph node metastasis or distant metastasis, were included. They were treated by the same surgeon of the Department of Head and Neck Surgery, Cancer Hospital, Chinese Academy of Medical Sciences from February 2014 to December 2020. 112 patients chose immediate surgery. The rest patients were asked to accept ultrasound examination every 6 months to 1 year. Follow-up endpoints: tumor size growth of 3 mm, tumor volume increase greater than 50%, lymph node metastasis or distant metastasis. Results: The median follow-up time was 19 months. 713 patients underwent surveillance for more than 6 months. Of the 713 patients, 570 (79.9%) were women, with mean age at 43.5 years old. Tumor progression was observed in 47 (6.6%) patients with a cumulative incidence of 2.7% (1 year), 7.2% (2 years) and 9.5% (3 years). In multivariate analysis, patient age [HR=0.508, 95%CI: 0.275-0.939, P=0.031], lesion number [HR=2.945, 95%CI: 1.593-5.444, P=0.001] and tumor size [HR=2.245, 95%CI: 1.202-4.192, P=0.011] at the beginning of observation were independent risk factors for tumor progression in patients with minimal thyroid malignant nodules during follow-up. During a median (range) active surveillance of 19 (6-80) months, 74 patients chose surgery during the surveillance. Among the 186 patients who underwent surgery, only 3 patients were diagnosed with fibrotic nodules in pathology, while the rest were papillary thyroid carcinoma. The ultrasound accuracy reached 98.4%(183/186). Conclusions: Ultrasonography is an effective method of diagnosing malignant thyroid nodules. Thyroid micro-malignant nodules progress slowly. As a result, it is safe to observe them instead of taking immediate surgery. Patient age, lesion number and tumor size at the beginning of observation are independent risk factors for the tumor progression of malignant nodules.目的： 评价对超声诊断的甲状腺微小恶性结节进行监测随访的效果，探讨甲状腺微小恶性结节避免过度治疗的管理策略。 方法： 收集2014年2月至2020年12月由中国医学科学院肿瘤医院同一位头颈外科医师接诊、同一位超声医师超声诊断为甲状腺微小恶性结节(肿瘤长径≤1.0 cm)、无区域淋巴结转移和远处转移的初诊患者949例，其中有112例患者选择立即手术治疗，其余患者接受以超声检查为主的监测随访。随访终点为肿瘤进展，包括较初诊时肿瘤长径增大≥3 mm或肿瘤体积增大≥50%、出现区域淋巴结转移或远处转移。 结果： 中位随访时间为19个月。在713例随访时间≥6个月的患者中，随访期间出现肿瘤进展47例(6.6%)，1、2、3年肿瘤进展累积发生率分别为2.7%、7.2%和9.5%，无1例患者出现远处转移。单因素Cox回归分析显示，患者的初诊年龄、病灶数量和肿瘤长径与甲状腺微小恶性结节患者随访期间肿瘤进展有关(均P<0.05)。多因素Cox回归分析显示，患者的初诊年龄(年龄>50岁：HR＝0.340，95%CI为0.133~0.866)、病灶数量(HR＝2.939，95%CI为1.590~5.431)和肿瘤长径(HR＝2.293，95%CI为1.226~4.289)是甲状腺微小恶性结节患者随访期间肿瘤进展的独立影响因素。随访期间74例患者选择手术治疗，与112例确诊后选择立即行手术治疗的患者合计，行手术治疗的患者共有186例，其中183例术后病理诊断为甲状腺乳头状癌，3例为纤维化结节。超声诊断甲状腺微小恶性结节的准确率达98.4%(183/186)。 结论： 超声是诊断甲状腺微小恶性结节的有效手段。甲状腺微小恶性结节进展缓慢，对其进行监测随访安全可行，有助于避免过度治疗。患者的初诊年龄、病灶数量和肿瘤长径是甲状腺微小恶性结节随访期间发生进展的独立影响因素。.