Department of Surgery, College of Medicine, The Catholic University of Korea, Daejeon St. Mary's Hospital, 520-2, Daeheung-dong, Jung-gu, Daejeon, South Korea.
World J Surg. 2011 Feb;35(2):318-23. doi: 10.1007/s00268-010-0886-5.
We examined the clinicopathologic features of papillary thyroid microcarcinomas (PTMCs) measuring≤7 mm and compared them with those of PTMCs>7 mm.
Between January 2007 and June 2009, a total of 275 patients with PTMCs underwent surgery. They were divided into two groups. Group I included patients with tumors≤7 mm, and group II included those with tumors>7 mm but ≤10 mm. We compared the two groups' clinicopathologic features.
Total thyroidectomy was more often performed in group II (p=0.003). Central lymph node metastases were identified in 30.6% of the patients in group I and in 47.8% of the patients in group II (p=0.005). A statistically significant difference between the two groups was also found for capsule invasion (p<0.0001), extrathyroidal extension (p=0.005), and lymphovascular invasion (p=0.025). On the multivariate analysis, central lymph node metastasis was the only independent factor associated with tumor size.
A PTMC≤7 mm is less likely to have aggressive features, including central lymph node metastasis, capsule invasion, extrathyroidal extension, and lymphovascular invasion, than a PTMC>7 mm. Because the aggressiveness of PTMC was found mainly in the patients with tumors >7 mm, we think that a cutoff value of 7 mm may be considered the threshold of aggressiveness of PTMCs.
我们研究了直径≤7 毫米的甲状腺微小乳头状癌（PTMC）的临床病理特征，并将其与直径>7 毫米的 PTMC 进行了比较。
2007 年 1 月至 2009 年 6 月期间，共有 275 例 PTMC 患者接受了手术。他们被分为两组。组 I 包括肿瘤直径≤7 毫米的患者，组 II 包括肿瘤直径>7 毫米但≤10 毫米的患者。我们比较了两组的临床病理特征。
组 II 中更常进行全甲状腺切除术（p=0.003）。组 I 中有 30.6%的患者存在中央淋巴结转移，组 II 中有 47.8%的患者存在中央淋巴结转移（p=0.005）。两组间在包膜侵犯（p<0.0001）、甲状腺外侵犯（p=0.005）和血管侵犯（p=0.025）方面也存在显著差异。多因素分析显示，中央淋巴结转移是与肿瘤大小相关的唯一独立因素。
与直径>7 毫米的 PTMC 相比，直径≤7 毫米的 PTMC 发生侵袭性特征（包括中央淋巴结转移、包膜侵犯、甲状腺外侵犯和血管侵犯）的可能性较小。由于 PTMC 的侵袭性主要发生在肿瘤直径>7 毫米的患者中，我们认为 7 毫米可能是 PTMC 侵袭性的阈值。
