Application value of fine needle aspiration and cell block in preoperative diagnosis of thyroid cancer and discrimination of follicular tumor

Abstract

To study the application value of fine needle aspiration and cell block combined with molecular markers in early diagnosis of thyroid cancer and discriminate follicular tumor before operation. Fine needle biopsy of thyroid nodules was guided by color ultrasound, then the sample acquired was used to make smear and the rest to make cell block. The pathological diagnosis on smear, cell block or combination of both was made respectively. Then, the Envision immunohistochemical method was employed to detect the expressions of CK19, Galectin-3 in cell block samples, which had been used for the diagnosis of papillary thyroid carcinoma or thyroid nodules from benign lesions after operation and to detect the expressions of DDIT3, ki-67 of cell block that had been used for the diagnosis of follicular tumor nodules. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of cytopathology for the diagnosis of malignancy were 95.3%, 94.7%, 92.7%, 96.6% and 95.0% respectively; and the sensitivity, specificity and accuracy of the diagnosis used cell block alone or combined with smear were 88.1%, 95.3%, 92.3% and 95.3%, 94.7%, 95.0% respectively, which were higher than 53.8%, 83.7%, 71.3% from smear correspondingly. The positive expression rate of CK19 and Galectin-3 of papillary thyroid carcinoma cell block were 100% and 98.0% respectively, higher than the value 17.7% and 23.3% of thyroid benign lesions (P < 0.01); the positive expression rate of DDIT3 of thyroid follicular cancer cell block was 84.6%, higher than the value 35.1% of follicular adenoma (P < 0.01), there was no statistical significance of Positive expression rate of Ki-67 between thyroid follicular carcinoma and follicular adenoma cell block (P > 0.05). It was conducive to early diagnose thyroid cancer with detection of CK19, Galection-3 of cell block made by ultrasound-guided fine needle biopsy of thyroid nodules. And it was also significant for DDIT3 detection to early discriminate follicular neoplasm before operation.