甲状腺结节大小对细针穿刺细胞学诊断结果的影响

The size of thyroid nodules contributing to the accuracy of fine-needle aspiration cytology

目的评价甲状腺结节大小对细针穿刺细胞学（FNAC）诊断准确性的影响。方法分析我院经手术病理证实的甲状腺结节患者630例691个结节，收集术前FNAC的诊断资料，根据Bethesda分类标准将细胞学结果分为6个级别：Ⅰ，细胞不足或无法诊断；Ⅱ，良性；Ⅲ，不典型增生；Ⅳ，滤泡性肿瘤；Ⅴ，可疑恶性；Ⅵ，恶性，以大于Ⅳ级作为诊断甲状腺恶性肿瘤标准。结节大小按长径（L）分：A组（L≤0．5cm）、B组（0．5cm〈L≤1．0cm）、C组（L〉1．0cm），以术后病理结果为诊断金标准。结果691个结节中A组176个（25．47％），B组298个（43．13％），C组217个（31．40％），三组间比较，B组超声引导下FNAC诊断甲状腺结节的准确率（90．94％）明显高于A组（80．11％）与C组（83．41％），差异具有统计学意义（P〈0．05），A组与c组间的差异无统计学意义（P〉0．05）；而三组间特异性、阴性预测值、阳性预测值的差异无统计学意义（P〉0．05）。结论甲状腺结节大小在一定程度上会影响超声引导下细针穿刺细胞学诊断的准确性。

Objective To evaluate the association of the size of thyroid nodules and accuracy of fine- needle aspiration cytology in diagnose of thyroid nodules. Methods 591 thyroid nodules in 530 patients pathologically confirmed were retrospectively analyzed in our hospital. All imaging data of preoperative ultrasound-guided FNAC were collected in our review.Yields of FNAC were divided into six levels according to the classification criteria of the Bethesda system（level Ⅰ ,insufficient material or nondiagnosed;level Ⅱ , benign ; level Ⅲ , atypical hyperplasia ; level Ⅳ follicular neoplasm ; level Ⅴ , suspicious for malignancy ; level Ⅵ, malignant） , 〉level Ⅳ was the malignant cytologic criteria for diagnosis of thyroid nodules.According to the maximal diameter of thyroid nodules, the nodules were divided into group A （L≤0.5 cm）, group B（0.5 cm〈L〈1.0 cm） and group C（L≥1.0 cm）.Postoperative pathologic results were taken as the gold standard. Results Of 691 nodules,there were 176（25.47%）,298（43.13%） and 217（31.40%） in group A,group B and group C respectively. Among the three groups, accuracy of ultrasound-guided FNAC in group B （90.94%） was higher than in group A（80.11%） and group C（83.41%）, with statistically significant（ P〈0.05）.There was not statistically different between group A and group C（ P 〉0.05）.The specificity,positive predictive value and negative predictive value were not statistically different among three groups（ P 〉0.05）. Conclusions The size of thyroid nodules was partly associated with accuracy of ultrasound-guided FNAC.