Lee Sung Hak, Kim Min Hee, Bae Ja Seong, Lim Dong Jun, Jung So Lyung, Jung Chan Kwon
Department of Hospital Pathology, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.
Ann Surg Oncol. 2014 Jun;21(6):1870-7. doi: 10.1245/s10434-013-3365-z. Epub 2014 Feb 14.
Patients with non-diagnostic thyroid fine needle aspiration cytology (FNAC) results undergo repeat FNAC or core needle biopsy (CNB) for definite diagnosis or surgical resection, or are followed up by clinical and ultrasound surveillance. We aimed at evaluating the risk of malignancy in patients with non-diagnostic FNACs and their clinical outcomes according to the follow-up modality.
We retrospectively reviewed 1,496 (8.8 %) cases with a non-diagnostic result on a first aspiration among 17,045 thyroid FNACs performed between October 2008 and August 2012. Of the non-diagnostic FNACs, 389 patients underwent a second FNAC; 125, CNB; and 89, thyroidectomy by clinical indication. The remaining patients were clinically followed up.
The rate of a second non-diagnostic result was significantly higher on repeat FNAC than on CNB (33.2 vs. 2.4 %; p < 0.001). There was no significant difference in the malignancy risk among patients initially non-diagnostic, twice non-diagnostic, and thrice or more non-diagnostic, nor did this differ from the rate following CNB. No further malignancy was found in cases with ≥2 non-diagnostic CNBs. The malignancy risk was 51 % in those who underwent thyroidectomy. The sensitivity for detecting malignancy was 65 and 70 % for repeat FNACs and first CNBs, respectively, with no false positives seen in either test.
Approximately one-third of repeat FNACs after an initial non-diagnostic aspirate are non-diagnostic on repeat examination, and the malignancy risk may not reduce following repetitively non-diagnostic FNACs. However, a single CNB may be enough to exclude malignancy risk for patients with a non-diagnostic aspirate.
甲状腺细针穿刺抽吸活检（FNAC）结果无法明确诊断的患者需接受重复FNAC或粗针活检（CNB）以明确诊断或进行手术切除，或者通过临床及超声监测进行随访。我们旨在根据随访方式评估FNAC结果无法明确诊断的患者的恶性肿瘤风险及其临床结局。
我们回顾性分析了2008年10月至2012年8月期间进行的17,045例甲状腺FNAC中首次抽吸结果无法明确诊断的1,496例（8.8%）病例。在FNAC结果无法明确诊断的患者中，389例接受了第二次FNAC；125例接受了CNB；89例根据临床指征进行了甲状腺切除术。其余患者进行了临床随访。
重复FNAC时第二次结果无法明确诊断的比例显著高于CNB（33.2%对2.4%；p<0.001）。最初结果无法明确诊断、两次结果无法明确诊断以及三次或更多次结果无法明确诊断的患者之间的恶性肿瘤风险无显著差异，与CNB后的发生率也无差异。在≥2次CNB结果无法明确诊断的病例中未发现进一步的恶性肿瘤。接受甲状腺切除术的患者的恶性肿瘤风险为51%。重复FNAC和首次CNB检测恶性肿瘤的敏感性分别为65%和70%，两种检测均未出现假阳性。
初次抽吸结果无法明确诊断后，约三分之一的重复FNAC在再次检查时结果仍无法明确诊断，且重复FNAC结果无法明确诊断后恶性肿瘤风险可能不会降低。然而，对于抽吸结果无法明确诊断的患者，单次CNB可能足以排除恶性肿瘤风险。
