探讨原发性甲状腺淋巴瘤（PTL）和甲状腺未分化癌（ATC）在临床、超声及病理上的差异，以提高超声医师对两者的认识及诊断准确率。

选取2008年1月至2017年8月经手术病理或穿刺活检证实的PTL患者41例，其中，男性11例，女性30例，年龄28~81岁，平均年龄（60.8±12.5）岁；另选取同期经手术病理证实的ATC患者16例，其中，男性7例，女性9例，年龄18~88岁，平均年龄（65.1±15.1）岁。对照分析两组患者的临床、超声及病理特征。PTL组和ATC组患者年龄及病灶最大径比较，采用两独立样本t检验；临床资料包括性别、颈部肿块短期增大、吞咽困难、呼吸困难、声音嘶哑、远处转移以及超声表现包括边界、边缘、回声水平、条索样或网格样高回声、钙化、囊性变、后方回声增强、血流、颈部淋巴结肿大的比较，采用χ²检验及Fisher确切概率法；采用受试者工作特征（ROC）曲线评价超声特征的诊断效能。

临床特征对比结果：PTL组患者声音嘶哑、远处转移的发生率均低于ATC组，两组比较，差异均有统计学意义（P均<0.05）；两组患者在年龄、性别、颈部肿块短期内迅速增大、呼吸困难、吞咽困难等方面，差异均无统计学意义（P均>0.05）。超声特征对比，PTL组极低回声、条索样或网格样高回声、后方回声增强较ATC组多见，钙化、囊性变较ATC组少见，以上各项两组比较，差异均有统计学意义（P均<0.05）。两组患者在病灶大小，边界，边缘，血流，颈部淋巴结肿大等方面，差异均无统计学意义（P均>0.05）。ROC曲线分析显示，极低回声、条索样高回声、后方回声增强、缺乏钙化及缺乏囊性变诊断PTL的敏感度分别为61.7%、74.5%、89.4%、100.0%、100.0%，特异度分别为81.0%、81.0%、100.0%、57.1%、33.3%，ROC曲线下面积分别为0.713、0.777、0.947、0.786、0.677。病理特征对比结果：PTL为单克隆性增殖，瘤细胞大小、形态较一致，间质纤维化较多见。ATC具有显著的结构及细胞异型性，癌细胞大小不等，明显多形性，可有不同程度的肿瘤性坏死。

PTL与ATC的临床表现相似；病理特征具有显著差异；超声表现均有一定特征性，超声特征如极低回声、条索或网格样高回声、后方回声增强、缺乏钙化及囊性变有助于两者的鉴别诊断。

To explore the differences in the clinical, ultrasound, and pathological features between primary thyroid lymphoma (PTL) and anaplastic thyroid carcinoma (ATC) to improve their diagnosis.

A total of 41 patients with PTL confirmed by surgical pathology or biopsy from January 2008 to August 2017 were selected. Among them, there were 11 males and 30 females, aged from 28 to 81 years old, with an average age of (60.8±12.5) years. In addition, 16 patients with ATC confirmed by surgical pathology were selected. Among them, there were 7 males and 9 females, aged between 18 and 88 years, with an average age of (65.1±15.1) years. The clinical, ultrasonic, and pathological findings of the two groups were analyzed retrospectively. Age and maximum diameter of the lesion were compared between the two groups using the two independent samples t-test. Clinical data including gender, short-term enlargement of neck mass, dysphagia, dyspnea, hoarseness, and distant metastasis, and ultrasonographic findings including border, margin, echogenicity, strip-like or grid-like hyperechoism, calcification, cystic degeneration, enhancement of posterior echo, blood flow, and cervical lymph node enlargement were compared using the 2 test and Fisher exact probability method. The diagnostic efficacy of ultrasonic characteristics was evaluated by ROC curve analysis.

The incidence of hoarseness and distant metastasis was significantly lower in patients with PTL than in those with ATC (P<0.05). There was no statistically significant difference between the two groups in terms of age, gender, rapid enlargement of neck mass, dyspnea, or dysphagia (P >0.05). Compared with the ATC group, marked hypoechogenicity, strip-like or grid-like hyperechogenicity, and enhancement of posterior echo were significantly more common, and calcification and cystic changes were significantly less common in the PTL group (P<0.05). There was no statistically significant difference between the two groups in lesion size, boundary, margin, or cervical lymph node enlargement (P>0.05). ROC curve analysis showed that the sensitivities of marked hypoechogenicity, strip-like or gridlike hyperechogenicity, enhancement of posterior echo, absence of calcification, and absence of cystic changes were 61.7%, 74.5%, 89.4%, 100%, and 100%, the specificities were 81.0%, 81.0%, 100%, 57.1%, and 33.3%, and the areas under the curves were 0.713, 0.777, 0.947, 0.786, and 0.677, respectively. PTL exhibited monoclonal proliferation, the size and shape of tumor cells were more consistent, and there was more interstitial fibrosis. ATC had obvious structure and cell atypia, and the size of cancer cells was heterogeneous, and different degrees of tumor necrosis might occur.

The clinical manifestations of PTL and ATC are similar, but their pathological features are significantly different. Sonographic features such as marked hypoechogenicity, homogeneity echo texture, strip like or grid like hyperechogenicity, enhancement of posterior echo, lack of calcification and cystic changes, and complication with Hashimoto thyroiditis are of important value in differentiating PTL and ATC.