Comparison of diagnostic efficacy of fine needle aspirate cytology, fine needle aspirate-thyroglobulin and BRAF gene in cervical metastatic lymph nodes of papillary thyroid carcinoma / 中国医学影像技术

ABSTRACT

Objective: To compare the diagnostic efficacy of fine needle aspirate cytology (FNAC), fine needle aspirate-thyroglobulin (FNA-Tg) and BRAF genetic testing in diagnosis of suspected cervical metastatic lymph nodes of PTC. Methods: A retrospective analysis was performed on 95 patients who received modified radical thyroidectomy and confirmed as PTC by pathology. Totally 118 suspected cervical metastatic lymph nodes found with ultrasound examination before or after modified radical thyroidectomy were all detected with FNAC, FNA-Tg and BRAF genetic testing. Taken postoperative pathology as gold standard, the sensitivity specificity, positive predictive value, negative predictive value and accuracy of three methods were obtained, and ROC curves were constructed to compare the diagnostic efficacy of three methods. Results: The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of FNAC was 63.95% (55/86), 100% (32/32), 100% (55/55), 50.79% (32/63) and 73.73% (87/118), respectively, of FNA-Tg was 91.86% (79/86), 100% (32/32), 100% (79/79), 82.05% (32/39) and 94.07% (111/118), respectively, while of BRAF genetic testing was 80.23% (69/86), 100% (32/32), 100% (69/69), 65.31% (32/49), 85.59% (101/118), respectively. AUC of FNAC, FNA-Tg and BRAF genetic testing was 0.820, 0.991 and 0.874, respectively. The differences of AUC between FNAC and FNA-Tg, BRAF genetic testing and FNA-Tg were statistically significant (P<0.001), whereas between FNAC and BRAF genetic testing was not statistically significant (P=0.099). Conclusion: FNA-Tg is more effective than FNAC and BRAF genetic testing in diagnosis of cervical suspected lymph node metastasis of PTC.