ObjectiveTo assess the effect of short-axis and long-axis punctures of thyroid nodules on the diagnostic rate of ultrasound guided aspiration biopsy (US-FNAB). MethodsWe retrospectively analyzed the clinical data of 2 686 thyroid nodule patients who underwent US-FNAB between March 2011 and November 2014. The US-FNAB was performed by 5 beginners (571 each for Dr1-Dr4 and 402 for Dr5). Yields of US-FNAB were divided into two levels according to the classification standard of the Bethesda system:adequacy and inadequacy. Short-axis puncture technique was used by Dr2 and long-axis puncture was performed by the others. According to chronological sequence of thyroid nodules examined, we compared the inadequate diagnostic rate between Dr2 and the others for the first 200 cases and the last 200 cases, respectively. The inadequate diagnostic rate was compared among the 4 doctors who used long-axis punctures for the first 200 cases and the last 200 cases, respectively. ResultsThe inadequacy rate of US-FNAB for Dr2 was higher than that for Dr1, Dr3, Dr4 and Dr5 in the first 200 cases, with statistical significance (P=0.036,<0.001,=0.007 and <0.001, respectively). There was no significant difference in inadequate diagnostic rate among the 4 doctors who used long-axis punctures for the first 200 cases (P=0.033, 0.551, 0.011, 0.122, 0.672 and 0.050). The inadequacy rate of US-FNAB for Dr2 was higher than that for Dr5 and lower than that for Dr4 in the last 200 cases with statistical significance (P=0.027 and 0.003, respectively). The inadequacy rate of US-FNAB for Dr5 was lower than that for Dr3 (P=0.005) and Dr4 (P<0.001) among the 4 doctors who used long-axis punctures for the last 200 cases. ConclusionFor beginners, the inadequacy rate of short-axis puncture is higher than long-axis puncture. We suggest beginners learn long-axis puncture method. There is no significant difference in inadequate diagnostic rate among short-axis and long-axis punctures, when the number of operated cases reaches 200. At this point, the operator can choose either way to puncture according to the disease condition or personal interests.
Objective To report our experience in using The Bethesda System for Reporting Thyroid Cytopathology(TBSRTC), and to investigate the diagnostic value of the system based on the cytologic-histologic result. Methods Pathological data of 2 257 thyroid nodules classified by TBSRTC which were obtained from the Department of Pathology of West China Hospital between Jan.2010 to Dec.2012 were collected and analyzed, to investigate the diagnostic evaluation indicators, such as the sensitivity, specificity, and diagnostic accuracy of the system based on the cytologic-histologic result. Results Of the 2 257 thyroid nodules, 442 (19.6%) were diagnosed as categoryⅠ, 1 184(52.4%) were diagnosed as categoryⅡ, 216(9.6%) were diagnosed as categoryⅢ, 38(1.7%) were diagnosed as categoryⅣ, 172(7.6%) were diagnosed as categoryⅤ, 205(9.1%) were diagnosed as categoryⅥ. Using TBSRTC categoryⅡas the boundary point of diagnosing benign and malignant diseases, the sensitivity, specificity, and diagnostic accuracy were 93.7%(236/252), 86.6%(323/373), and 89.4%(559/625)respectively, while categoryⅢwas excluded from analysis. When including categoryⅢinto analysis, the sensitivity, specificity, and diagnostic accuracy were 94.3%(267/283), 74.9%(323/431), and 82.6%(590/714)respectively. Conclusion The validity of TBSRTC was high at our institution. TBSRTC has proven to be an accurate and reliable approach for the diagnosis of thyroid nodules.