^(99)Tc^(m)O_(4)^(-)核素显像与血清TSH水平对超声检查提示高危甲状腺结节的鉴别诊断价值

Differential diagnostic value of^(99)Tc^(m)O_(4)^(-) thyroid scintigraphy and serum TSH in high-risk thyroid nodules revealed by ultrasonography

目的探讨^(99)Tc^(m)O_(4)^(-)核素显像与血清促甲状腺激素(TSH)水平对甲状腺影像报告和数据系统(TI-RADS)4级甲状腺结节(TN)良恶性鉴别诊断的临床应用价值。方法回顾性分析2017年10月至2019年12月于桂林医学院附属医院接受TN切除术或细针穿刺细胞学检查明确诊断的201例TN患者资料(甲状腺超声检查、^(99)Tc^(m)O_(4)^(-)核素显像和血清TSH水平检测),其中男性54例、女性147例,年龄20~75(49.1±13.2)岁。以术后组织病理学检查结果为“金标准”,将所有患者分为恶性TN组和良性TN组;根据超声检查结果中结节的长径将恶性TN组和良性TN组中所有结节分别分为3个亚组:长径≤10 mm、10 mm<长径≤20 mm、长径>20 mm。采用两独立样本t检验、独立四格表χ^(2)检验比较2组患者的基本资料,多组间比较采用单因素方差分析;采用受试者工作特征曲线分析TSH水平诊断良恶性TN的最佳临界值,并计算诊断效能;采用趋势χ^(2)检验分析术前TSH水平与甲状腺癌的相关性。结果201例患者均为单发TN,其中恶性TN组62例、良性TN组139例。组织病理学检查结果显示,201个TN中,甲状腺癌62个(30.8%)、结节性甲状腺肿33个(16.4%)、甲状腺腺瘤81个(40.3%)、结节性甲状腺肿伴腺瘤25个(12.4%);超声检查结果显示,201个TN中,TI-RADS 4a级81个(40.3%),其中甲状腺癌9个(11%);TI-RADS 4b级70个(34.8%),其中甲状腺癌20个(29%);TI-RADS 4c级50个(24.9%),其中甲状腺癌33个(66%);^(99)Tc^(m)O_(4)^(-)核素显像结果显示,201个TN中,冷结节110个(54.7%),其中甲状腺癌40个(36.4%);凉结节67个(33.3%),其中甲状腺癌22个(33%);温结节24个(11.9%),无恶性TN。甲状腺^(99)Tc^(m)O_(4)^(-)核素显像联合超声检查结果显示,凉、冷结节且超声检查分级为TI-RADS 4c级的结节恶性率(72%,33/46)最高。恶性TN组患者术前TSH水平较良性TN组高,分别为(1.59±0.32)、(1.29±0.45)μIU/mL,且差异有统计学意义(t=4.752,P<0.01)。趋势χ^(2)检验分析结果显示,随着TSH水平的升高,TN恶性率也随之升高(χ^(2)=27.513,P<0.01),而恶性TN组中长径≤10 mm、10 mm<长径≤20 mm、长径>20 mm的患者术前TSH水平的差异无统计学意义(F=0.223,P=0.800)。对于术前良恶性TN的鉴别,TSH水平诊断的最佳临界值为1.525μIU/mL,曲线下面积为0.741(95%CI:0.666~0.816)、灵敏度为75.8%、特异度为70.5%。结论^(99)Tc^(m)O_(4)^(-)核素显像提供的功能状态信息进一步提高了TI-RADS 4级TN的鉴别诊断效能,而术前TSH水平在术前评估中的作用尚不明确。

Objective To evaluate the diagnostic value of^(99)Tc^(m)O_(4)^(-)thyroid imaging and serum thyroid stimulating hormone(TSH)for differentiating benign and malignant thyroid imaging reporting and data system(TI-RADS)category-4 thyroid nodules(TNs).Methods The clinical data(thyroid ultrasonography,^(99)Tc^(m)O_(4)^(-)thyroid scintigraphy,and TSH levels)of 201 TN patients who underwent surgery or fine-needle aspiration cytology diagnosis from October 2017 to December 2019 at the Affiliated Hospital of Guilin Medical College were analyzed retrospectively.Among these patients,54 were males and 147 were females,aged 20–75(49.1±13.2)years.Post-operative histopathology result was used as the gold standard to classify the patients as malignant TN and benign TN groups.The TN group was divided into three subgroups based on the maximum nodule diameter through ultrasonography:diameter≤10 mm,10 mm<diameter≤20 mm,diameter>20 mm.The basic data of the two groups were compared using two-sample t-test and independent four-cell table chi-square test,and one-way ANOVA was used for the comparison among groups.Receiver operating characteristic(ROC)curve analysis was adopted to determine the optimal cutoff value of TSH between malignant and benign TNs,and the diagnostic efficiency was calculated.Trend chi-square test was conducted to assess the relationship between TSH level and thyroid carcinoma.Results All 201 patients had a single TN,of which 62 were in malignant TN group,139 were in benign TN group.The histopathological findings revealed that among the 201 TNs,62 were thyroid cancer(30.8%),33 were nodular goiter(16.4%),81 were thyroid adenomas(40.3%),and 25 were nodular goiter with adenoma(12.4%).Ultrasonography results revealed that 81 were TI-RADS 4a nodules(40.3%),including 9 thyroid cancer(11%);70 were TI-RADS 4b nodules(34.8%),including 20 thyroid cancer(29%);and 50 were TI-RADS 4c nodules(24.9%),including 33 thyroid cancer(66%).The findings of^(99)Tc^(m)O_(4)^(-)thyroid scintigraphy demonstrated that 110 were cold nodules(54.7%),including 40 thyroid cancer(36.4%);67 were cool nodules(33.3%),including 22 thyroid cancer(33%);and 24 were warm nodules(11.9%),without malignant TNs.The malignant rate of TI-RADS 4c cool or cold nodules was determined to be the highest by using the combination of^(99)Tc^(m)O_(4)^(-)thyroid scintigraphy and ultrasonography(72%,33/46).The preoperative serum TSH levels of the malignant TN group[(1.59±0.32)μIU/mL]were higher than those of the benign TN group[(1.29±0.45)μIU/mL],and the difference was statistically significant(t=4.752,P<0.01).Trend chi-square test showed that a higher TSH level was correlated with a higher incidence of thyroid cancer(χ^(2)=27.513,P<0.01).However,no statistical differences in preoperative serum TSH levels were found among the three different-diameter malignant TN groups(F=0.223,P=0.800).ROC curve analysis showed the optimum cutoff value of TSH for differential diagnosis between malignant and benign TNs.The diagnostic efficiency of TSH was the highest at 1.525μIU/mL,with an area under curve of 0.741(95%CI:0.666–0.816),specificity of 75.8%,and sensitivity of 70.5%.Conclusions^(99)Tc^(m)O_(4)^(-)thyroid scintigraphy may help evaluate the^(99)Tc^(m)O_(4)^(-)uptake functions of TNs,which clearly improved the diagnostic accuracy for TI-RADS category-4 TNs in clinical work.The role of preoperative serum TSH in the presurgical evaluation of TNs remains unclear.