Department of Radiology, Chung-Ang University Hospital, 224-1 Heukseok-dong, Dongjak-gu, Seoul 156-755, Korea.
J Ultrasound Med. 2014 Feb;33(2):231-8. doi: 10.7863/ultra.33.2.231.
The purpose of this study was to evaluate the diagnostic performance and predictive factors of extrathyroidal extension of papillary thyroid carcinoma based on preoperative sonography.
Preoperative sonography was performed for 568 patients who underwent surgery for papillary thyroid cancer between May 2009 and December 2010. Patients' T stages based on preoperative sonography were compared with their T stages based on pathologic examination, and we statistically analyzed the discriminatory performance of sonography. Among the 568 patients enrolled in this study, we selected 320 patients in whom extrathyroidal extension was suspected on sonography. We analyzed several predictive factors for extrathyroidal extension.
Two hundred seventy-five of the 568 patients were proven to have pathologic extrathyroidal extension of papillary thyroid cancer after surgery (75.9% diagnostic accuracy, 83.3% sensitivity, 68.9% specificity, 71.6% positive predictive value, and 81.5% negative predictive value). Of 320 patients with sonographically suspected extrathyroidal extension, a larger lesion size (P < .001) and a higher lymph node stage on sonography (P = .004) were the best predictors of extrathyroidal extension among the features that we measured. There were no significant differences in terms of the lesion site or thyroid parenchymal background echogenicity. Thyroid capsular protrusion had a higher predictive value than the abutting ratio (P = .001). However, increasing the abutting ratio enabled the prediction of extrathyroidal extension on sonography (P = .009).
Preoperative sonography is a helpful tool for predicting pathologic extrathyroidal extension of papillary thyroid cancer. In particular, clinicians should focus on the lesion size, nodal stage, and abutment or capsular protrusion of the lesion while performing sonography because these are the most useful predictive factors for extrathyroidal extension.
本研究旨在评估基于术前超声的甲状腺乳头状癌甲状腺外侵犯的诊断性能和预测因素。
对 2009 年 5 月至 2010 年 12 月期间因甲状腺乳头状癌接受手术的 568 例患者进行了术前超声检查。将患者基于术前超声的 T 分期与基于病理检查的 T 分期进行比较，并对超声的鉴别性能进行了统计学分析。在本研究纳入的 568 例患者中，我们选择了 320 例在超声检查中怀疑有甲状腺外侵犯的患者。我们分析了几个甲状腺外侵犯的预测因素。
275 例 568 例患者术后证实有甲状腺乳头状癌的病理甲状腺外侵犯（诊断准确率为 75.9%，敏感性为 83.3%，特异性为 68.9%，阳性预测值为 71.6%，阴性预测值为 81.5%）。在 320 例超声怀疑有甲状腺外侵犯的患者中，病灶大小较大（P<.001）和超声淋巴结分期较高（P=0.004）是我们测量的特征中预测甲状腺外侵犯的最佳指标。病变部位或甲状腺实质背景回声强度无显著差异。甲状腺包膜外突的预测价值高于毗邻比（P=0.001）。然而，增加毗邻比可以提高超声对甲状腺外侵犯的预测能力（P=0.009）。
术前超声是预测甲状腺乳头状癌甲状腺外侵犯的有用工具。特别是在进行超声检查时，临床医生应重点关注病灶大小、淋巴结分期以及病灶的毗邻或包膜外突，因为这些是预测甲状腺外侵犯最有用的预测因素。
