1 Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine , Seoul, Korea.
2 Department of Internal Medicine, Hallym University Kangdong Sacred Heart Hospital , Seoul, Korea.
Thyroid. 2018 Aug;28(8):997-1003. doi: 10.1089/thy.2018.0046. Epub 2018 Jul 24.
Low-risk patients with differentiated thyroid cancer can be treated with thyroid lobectomy. Serial measurements of serum thyroglobulin (Tg) are recommended for surveillance, but the cutoff values indicating recurrence are not known. This study documented the natural course of serum Tg levels during follow-up after lobectomy for low-risk papillary thyroid carcinoma (PTC) and evaluated whether changes in serum Tg levels predict disease recurrence.
This historical cohort study included 208 patients with low-risk PTC who underwent lobectomy but did not require hormone replacement. Postoperative serum Tg levels and Tg/thyrotropin (TSH) ratios and neck ultrasound were evaluated during a follow-up period with a median of 6.9 years.
The serum Tg levels increased gradually, and the proportion of patients with levels >10 ng/dL increased annually by 13.9%, 18.8%, 22.1%, 21.9%, 28.4%, and 28.9% during the six-year follow-up period (β = 0.574, p = 0.027). The relative serum Tg levels increased by 10% annually (β = 0.105, p < 0.001), and the levels of Tg and Tg/TSH ratios in 19 patients with recurrent disease did not differ significantly (β = 0.150, p = 0.090). Patients without recurrent disease were more likely to have serum Tg levels increased by >20% (p = 0.022). There were no significant differences in the proportions of patients with serum Tg levels increased by ≥50% or ≥100% in terms of the disease recurrence.
Serum Tg levels and the Tg/TSH ratio increased gradually after lobectomy in patients with and without recurrences, without any significant differences. Periodic measurements of serum Tg levels seem to have limited value in predicting recurrent PTCs after lobectomy.
低危分化型甲状腺癌患者可以采用甲状腺叶切除术进行治疗。建议对患者进行血清甲状腺球蛋白（Tg）的连续测量，以进行监测，但尚无提示复发的截断值。本研究记录了低危甲状腺乳头状癌（PTC）患者甲状腺叶切除术后随访期间血清 Tg 水平的自然变化过程，并评估了血清 Tg 水平的变化是否可以预测疾病复发。
这是一项回顾性队列研究，共纳入 208 例接受甲状腺叶切除术但无需激素替代治疗的低危 PTC 患者。在中位随访时间为 6.9 年的期间内，评估了术后血清 Tg 水平、Tg/促甲状腺激素（TSH）比值以及颈部超声。
血清 Tg 水平逐渐升高，在六年的随访期间，每年超过 10ng/dL 的患者比例分别增加了 13.9%、18.8%、22.1%、21.9%、28.4%和 28.9%（β=0.574，p=0.027）。相对血清 Tg 水平每年增加 10%（β=0.105，p<0.001），且 19 例复发患者的 Tg 水平和 Tg/TSH 比值并无显著差异（β=0.150，p=0.090）。无疾病复发的患者更可能出现 Tg 水平升高超过 20%（p=0.022）。在疾病复发方面，Tg 水平升高≥50%或≥100%的患者比例无显著差异。
在有或无复发的患者中，甲状腺叶切除术后血清 Tg 水平和 Tg/TSH 比值逐渐升高，无显著差异。定期测量血清 Tg 水平对预测甲状腺叶切除术后复发的 PTC 似乎价值有限。
