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The extent of human sodium iodide symporter (hNIS) expression in different kinds of human thyroid cancer tissues and cell lines remains controversial. In this study, polyclonal antibodies to hNIS were used to analyze the expression of symporter protein in benign and malignant human thyroid tissues. Formalin-fixed, paraffin wax-embedded tissue sections were used. Staining was performed using primary polyclonal antibody of rabbit anti-human hNIS diluted in PBS (1:500). Results showed that 2 of 3 normal tissue, 3 of 6 nodular hyperplasia, one follicular adenoma, 3 of 11 papillary thyroid carcinoma, 1 of 5 follicular carcinoma and none of 3 metastatic thyroid epithelial tissue specimens stained positively for hNIS. A higher percentage of positive staining for symporter protein was found in benign thyroid tissues including normal thyroid tissue, nodular hyperplasia, and adenoma (60%). In contrast, papillary and follicular thyroid carcinomas demonstrated lower symporter protein expression (20%). In conclusion, although the number of tissue samples examined in this study was small, hNIS staining found a higher ratio of symporter protein expression in normal and benign thyroid tissues compared with malignant tissues. Determination of the reason for discrepancies in the expression of hNIS in in vivo and in vitro studies will require further investigation.

Thyroid neoplasm is the most commonly encountered neoplastic disorder in endocrine clinics. Thyroid scan, ultrasonography, and fine needle aspiration cytology (FNAC) are used as diagnostic tools to differentiate a malignant nodule from a benign lesion. There are certain limitations and pitfalls in FNAC, especially in the diagnosing of follicular tumors. The lack of characteristic findings or a specific tumor marker are the most common problems in the preoperative diagnosis of thyroid follicular carcinoma. Although serum thyroglobulin level has been used as a tumor marker for post-operative, well-differentiated thyroid cancer, the assay cannot be used for preoperative diagnosis of thyroid carcinoma. In this study, various thyroid tissues and cancer cell lines including CGTH W-1, CGTH W-3, RO 82 W-1, SW 579 cell lines were used for the investigation of tumor markers. Specific spots were identified in the area near the 60 kDa molecular mass protein and isoelectric point (pI) 5.9 of the CGTH W-1 cell line. These spots could not be found in the papillary or anaplastic thyroid cancer cell lines. Another spot with a molecular weight of about 9.8 kDa with a low pI of 4.8 was present in the CGTH W-1 and RO 82 W-1 cell lines. This spot appeared to be a tumor marker of follicular cancer cells. This spot could not be found in the papillary and anaplastic cancer cell lines and other benign thyroid tissues. Specific proteins that were identified in this study may be useful as tumor markers for follicular thyroid carcinoma.

Aims: To evaluate the correlation of fine needle aspiration (FNA) cytology and frozen section biopsy in the diagnosis of thyroid nodules., Methods: The medical records of 662 patients who underwent FNA cytology of the thyroid and thyroid surgery were analysed. Frozen section biopsies were taken from 586 of the 662 patients. The diagnostic correlations of FNA cytology, frozen section, and both FNA cytology and frozen section with definitive histological assessment were evaluated., Results: Among the 662 patients who received FNA cytology, there were 356 cases (53.8%) diagnosed as benign, 114 cases (17.2%) as malignant, 148 cases (22.4%) as indeterminate, and 44 cases (6.6%) as unsatisfactory. The positive predictive value for the detection of malignancy by FNA cytology was 92.1% and the negative predictive value was 95.2%. The incidence of malignancy in the indeterminate cytological diagnosis was 23%. The diagnosis from frozen sections was benign in 445 cases (75.9%), malignant in 134 cases (22.9%), and deferred in 7 cases (1.2%). By frozen section, the positive and negative predictive values were 97% and 95.5%, respectively. Diagnostic accuracy up to 98% was achieved when FNA cytology and frozen section diagnoses were in agreement. No false positives were observed when FNA cytology and frozen sections were both positive for malignancy. When FNA cytology and frozen section diagnoses were discordant, frozen section showed a higher accuracy (78.9%) than FNA cytology (21.1%). In the face of an indeterminate or unsatisfactory cytological diagnosis, the diagnostic accuracy of frozen sections reached 92.6%., Conclusions: The results confirm that FNA cytology is a useful tool in the initial evaluation of thyroid nodules. Intraoperative frozen section is a valuable procedure to confirm the cytological diagnosis and identify malignancy in patients with indeterminate or unsatisfactory cytological diagnosis. With reliance on frozen sections as an intraoperative guide of thyroid surgery, the possibility of unnecessary extensive surgery and the need for the second operation are considerably lower.

Objective: To assess the role of ultrasonography and fine needle aspiration cytology (FNAC) in preoperative diagnosis of patients with occult thyroid carcinoma (OTC)., Study Design: Data on 768 thyroid carcinoma patients receiving primary treatment at Chang Gung Medical Center were retrospectively reviewed. Of these patients, 97 had OTC. To detect small thyroid nodules early and define the characteristics of clinically palpable nodules, thyroid ultrasonography with FNAC were performed on 67 histopathologically proven OTC patients. Analysis for diagnostic value was done for ultrasonography and FNAC., Results: In the 67 patients receiving ultrasonography with FNAC, 23 were preoperatively diagnosed as having papillary thyroid carcinoma and 1 as having follicular carcinoma. The tumor size of these 24 preoperative FNAC-proven OTC was 0.81 +/- 0.23 cm (mean +/- SD). In the remaining patients, 10 presented pictures suspicious for malignancy, with a mean tumor size 0.63 +/- 0.24 cm, and 33 (49.3%) were diagnosed as having benign thyroid lesions in preoperative FNAC. The tumor size in these 33 lesions was 0.58 +/- 0.24 cm. Fifty-seven of the 67 OTC patients received frozen sections. Thirty-eight papillary thyroid carcinomas and four follicular carcinomas were correctly diagnosed on frozen sections., Conclusion: Although the rate is not high, high-resolution ultrasonography and FNAC is the best approach to preoperative diagnosis for OTC patients today.

This series retrospectively reviewed 3657 patients who received thyroid ultrasonography with fine-needle aspiration cytological (FNAC) examinations at Chang Gung Memorial Hospital during the period from January 1, 1993 to December 31, 1993. Thyroid ultrasonography studies were performed using a real-time ultrasonographic machine with a 10 MHz transducer. The aspirates were air dried and stained by the Romanowsky-based Liu method. Three hundred seventy-eight cases (10.3%) received surgical treatment after the ultrasonographic and FNAC examinations. Benign lesions were diagnosed in 269 patients. Thyroid malignancy was confirmed histopathologically in 109 cases including 76 papillary thyroid carcinomas, 17 follicular carcinomas, 5 medullary thyroid carcinomas, 3 anaplastic carcinomas, 3 Hürthle cell carcinomas, and 3 lymphomas. Another 2 cases were metastatic cancer to thyroid. The results demonstrated that 28.8% of the surgically treated patients had histopathologically proven malignancies. The incidence of thyroid malignancy was 2.98% in this study. The sensitivity of the cytological diagnosis was 79.80% and the specificity was 98.66%. The positive predictive value was 96.34%. Negative predictive value was 91.70%. The false negative index was 20.20%. The diagnostic accuracy was 92.89%. Thyroid ultrasonography with the FNAC can provide high specificity and sensitivity in differentiating malignant lesions from benign.

In this study two-dimensional (2D) polyacrylamide gel electrophoresis with silver staining was used to analyze cellular membranous proteins of various normal and pathological human thyroid tissues. The aim was to understand the differences in cellular membranous proteins between these tissues, which would aid in the differential diagnosis of thyroid malignancy. Characteristic protein spots had a molecular mass of 50-64 kDa and a pI of 5.7-6.5. There were two groups of isoform protein spots in this area. The higher-molecular-mass group was found in follicular thyroid cancer tissues which and was not visible in normal thyroid tissues. The low-molecular-mass group was found in follicular carcinoma or adenoma tissues and was detected in one to three spots. The papillary thyroid carcinoma tissues gave different 2D gel maps. There were few spots of papillary thyroid carcinoma tissue membranous proteins within the examined area. The 2D gel maps may be used for differential diagnosis of follicular neoplasm. The characteristics of these protein spots require further investigation.

Although acute suppurative thyroiditis is a rare disorder, from January. 1985 to December 1991, we observed 11 cases of acute suppurative thyroiditis in our hospital. All patients underwent thyroid ultrasonography and fine needle aspiration biopsy and cytologic evaluation of the specimens. In eight cases, pus cultures were positive, four of them grew Gram negative bacteria. Ultrasonographic finding showed either local or diffuse low to a very low echo density on both lobes. However, a cystic lesion was also found. Polymorphonuclear cells were the main elements in the smears from the thyroid aspirates. In conclusion, thyroid ultrasound with fine needle aspiration and cytology can assist in confirming the early diagnosis of acute suppurative thyroiditis.