Potential diagnostic markers in nodular lesions of the thyroid gland: an immunohistochemical study

Aims: The differential diagnosis of thyroid nodules in routine practice can be problemmatic for both pathologists and clinicians. Effective treatment requires a determination of the biological nature of the lesions. For this reason, ancilliary diagnostic markers along with histological examination of the nodules may be useful. The objective of this study was to evaluate the diagnostic usefulness of novel markers in the diagnosis of hyperplastic and neoplastic nodules. Methods: Forty eight thyroid lesions forming four diagnostic groups including adenomatous goiters (AS), follicular adenomas (FA), follicular (FC) and papillary carcinomas (PC) were examined using standard immunohistochemical methods. Monoclonal antibodies against galectin-3, matrix metalloproteinases (MMPs) -2 and -7 and endothelial markers CD31 and CD105 were used. Results: The cytoplasmatic expression of galectin-3 was positive in all cases of papillary carcinoma. Moreover, statistically significant differences between fused groups of benign (AS and FA) and malignant lesions (FC and PC) were found Fischer's exact test (p = 0.0001). No significant differences in cytoplasmic expression of MMPs -2 and -7 and in vascular density assessed by using of both endothelial markers between benign lesions and malignant tumors were revealed. Conclusions: Galectin-3 appears to be a useful marker in the diagnosis of papillary carcinoma only. The matrix metalloproteinases-2 and -7 are not helpful in distinguishing hyperplastic and neoplastic thyroid nodules. Endothelial markers do not appear to be suitable for thyroid differential diagnosis. A panel of antibodies in the differential diagnosis of thyroid nodular lesions would seem most suitable and further studies with larger sets of patients are awaited.     

Galectin-3 is not useful in thyroid FNA

INTRODUCTION: Previous studies have suggested that galectin-3 immunohistochemistry may be useful in the fine needle aspiration (FNA) diagnosis of thyroid carcinoma as it has been reported to selectively stain carcinomas and not adenomas or goitres. METHODS: Fifty-one patients were included in a prospective study of galectin-3 in thyroid FNA; 88.2% were female and 11.8% male, mean age 53 years, range 25-87 years. Cell blocks were prepared and stained for galectin-3 if any cells were present in needle washings from the respective FNAs. RESULTS: Twelve of 51 (23.5%) of cell blocks contained epithelial cells. One benign and one inadequate FNA were negative for galectin-3 staining. One of five non-diagnostic FNA cases, a papillary carcinoma on final histology showed positive staining. Four follicular neoplasm/suspicious of carcinoma cases showed negative staining. One malignant FNA case, a papillary carcinoma showed positive staining with galectin-3 but three further carcinomas, two papillary and one follicular were galectin-3 negative. CONCLUSION: Galectin-3 immunohistochemistry does not appear to be a useful adjunct to diagnosis in thyroid FNA as it does not reliably distinguish malignant and benign lesions. Many thyroid aspirates are of low cellularity and are not suitable for cell block immunohistochemistry.     

Diagnostic utility of galectin-3 in aspirates of thyroid follicular lesions

OBJECTIVE: To investigate the expression of galectin-3 in various thyroid follicular lesions, including diffuse hyperplasia, nodular hyperplasia, and benign and malignant follicular neoplasms, to clarify the diagnostic utility of galectin-3 in aspirates of follicular lesions. STUDY DESIGN: A total of 146 follicular lesions diagnosed cytologically, obtained from patients who had undergone thyroidectomy for either benign or malignant nodules, were evaluated using Papanicolaou-stained slides and cell blocks with galectin-3 immunostaining. We primarily categorized the aspirated specimens as benign, indeterminate or suspicious for a follicular neoplasm based on cellularity, architectural arrangement of the follicular cells and presence or absence of colloid. Galectin-3 immunostaining was evaluated according to the proportion and intensity of positively stained cells. Cytologic diagnoses were correlated with the results of galectin-3 and categorized into 3 groups (benign, indeterminate for malignancy, suspicious for malignancy) and compared with the corresponding histologic diagnoses. RESULTS: When the histologic diagnoses were compared with the cytologic diagnoses, the accuracy in the distinction between benign and malignant cases was 79.5% except for 8 cytologically and 3 histologically indeterminate cases. Except for 11 indeterminate cases, there were 18 (12.3%) discrepant cases. False positive cases included 8 of 62 (12.9%) nodular hyperplasias and 1 of 42 (2.4%) follicular adenomas. Of 9 false negative cases, 4 minimally invasive carcinomas and 2 widely invasive carcinomas were included. Three follicular tumors of uncertain malignant potential were cytologically categorized as malignant, and all cases showed positivity for galectin-3. CONCLUSION: Galectin-3 could be used as a useful supplementary marker for cytologic diagnosis, although it was not an absolute marker in determining whether a lesion was benign or malignant.     

Expression of the selected adhesive molecules (cadherin E, CD44, LGAL3 and CA50) in papillary thyroid carcinoma

INTRODUCTION: The aim of the study was to determine the expression of selected adhesive molecules in papillary thyroid carcinoma. MATERIAL AND METHODS: 47 papillary thyroid carcinoma cases and 11 nonmalignant goiter cases were analyzed by immunohistochemistry. RESULTS: Galectin-3 (LGAL3) was a sensitive and specific marker, present in 91% of analyzed tumors and only in 5% of tumor margin. The presence of CA50 was 86% and 3% respectively with only 3% positive non-malignant cases. Cadherin E expression was noted in 91% of primary tumors, in 84% of the surrounding tissue and in 63% of non-malignant goiter. CD44 (DF1485) was observed in 89% of primary tumors and 48% of surrounding tissue; the reaction with BBA10 was more characteristic for metastases. CONCLUSIONS: Our study confirms the high diagnostic value of galectin-3 in papillary thyroid carcinoma and reveals the similar efficiency of CA50. CD44 (DF1485) expression in primary tumor is more intensive than in surrounding tissue, but the diagnostical inportance is not high because it is often observed in benign lesions. Using of BBA10 is more sensitive, but less specific. High expression of cadherin E in benign lesions impairs its diagnostical application in papillary thyroid cancer.     

Split sample comparison of a liquid-based method and conventional smears in thyroid fine needle aspiration

OBJECTIVE: To compare the efficacy of the SurePath (SP) vs. conventional smears (CS) in fine needle aspiration (FNA) of thyroid gland lesions. STUDY DESIGN: A total of 193 FNA cases with thyroid nodules were studied. Samples from ultrasound-guided FNA were split to prepare CS and SP slides. The diagnostic categories of unsatisfactory, benign, atypical and malignant were compared. Galectin-3 immunostaining was performed on SP slides. RESULTS: Some differences were found between the cytomorphology of CS and SP. SP slides showed more increased cellularity and more clustered tissue fragments. On SP slides, nuclear detail and nucleoli were more easily detected and nuclear irregularity was very useful for the diagnosis of papillary carcinoma. SP showed a trend toward a lower proportion of atypical category. The overall sensitivity of FNA in diagnosing thyroid neoplasm was 90.9% for CS and 93.9% for SP. Most lesions (73%) diagnosed as papillary carcinoma after surgery showed positive staining of galectin-3. CONCLUSION: The SP method showed easy evaluation of cytomorphologic features and consistent specimen quality and appeared to be more useful in diagnosing the suspicious cases. Moreover, it offered the possibility of adjunctive immunocytochemistry on the same sample.     

Proliferative activity of papillary carcinoma and benign papillary hyperplasia of thyroid follicular cells

Papillary structures of follicular cells are observed in nodular goiter, cysts, hyperplastic areas of follicular tumors, Graves' disease, thyroiditis and carcinomas. The distinction of papillary carcinomas from benign lesions has important implication for clinical management. The aim of the study was to test a marker of proliferation activity (MIB-1) in the diagnosis of benign and malignant thyroid papillary proliferation. The study was carried out in 98 women with papillary carcinoma, nodular goiter. intracystic proliferation. Graves' disease and hyperplastic areas of follicular benign tumors. The formalin fixed, paraffin-embedded specimens were microscopically examined using HE staining and immunostaining with MIB-1 antibody (DAKO). The proliferative index (PI) was significantly higher in malignant than in benign papillary hyperplasia. Our results may provide additional information for differential papillary proliferation diagnosis by FNAB.     

Differential Protein Expression Profiles of Cyst Fluid from Papillary Thyroid Carcinoma and Benign Thyroid Lesions

Cystic papillary thyroid carcinoma (cPTC) is a subgroup of PTC presenting a diagnostic challenge at fine needle aspiration biopsy (FNAB). To further investigate this entity we aimed to characterize protein profiles of cyst fluids from cPTC and benign thyroid cystic lesions. In total, 20 cPTCs and 56 benign thyroid cystic lesions were studied. Profiling by liquid chromatography tandem mass spectrometry (LC-MS/MS) was performed on cyst fluids from a subset of cases after depletion, and selected proteins were further analyzed by Western blot (WB), immunohistochemistry (IHC) and enzyme-linked immunosorbent assay (ELISA). A total of 1,581 proteins were detected in cyst fluids, of which 841 were quantified in all samples using LC-MS/MS. Proteins with different expression levels between cPTCs and benign lesions were identified by univariate analysis (41 proteins) and multivariate analysis (59 proteins in an orthogonal partial least squares model). WB analyses of cyst fluid and IHC on corresponding tissue samples confirmed a significant up-regulation of cytokeratin 19 (CK-19/CYFRA 21-1) and S100A13 in cPTC vs. benign lesions. These findings were further confirmed by ELISA in an extended material of non-depleted cyst fluids from cPTCs (n = 17) and benign lesions (n = 55) (p<0.05). Applying a cut-off at >55 ng/ml for CK-19 resulted in 82% specificity and sensitivity. For S100A13 a cut-off at >230 pg/ml revealed a 94% sensitivity, but only 35% specificity. This is the first comprehensive catalogue of the protein content in fluid from thyroid cysts. The up-regulations of CK-19 and S100A13 suggest their possible use in FNAB based preoperative diagnostics of cystic thyroid lesions.     

Cytologic Features of Focal Papillary Thyroid Carcinoma Arising within Follicular Adenoma: A Masked Cytomorphologic Analysis of 17 Cases

Background/Objective: Focal papillary thyroid carcinoma (PTC) arising within a follicular adenoma (PTCFA) represents a clinically significant, but rare, histopathologic subset of papillary carcinomas whose cytologic features have not been well described. This uncommon presentation of PTC may contribute to a subset of thyroid aspirates interpreted as 'atypia of undetermined significance/follicular lesion of undetermined significance' (AUS/FLUS). Study Design: Seventeen fine-needle aspiration biopsy (FNAB) cases diagnosed as 'PTCFA' on corresponding surgical excision were identified from the archival records of 2 large academic medical centers. A control group of 40 FNAB comprised of 20 follicular adenomas (FA) and 20 PTC was identified (based on the corresponding surgical pathology diagnosis) for comparison. All 57 FNAB were reviewed in a masked fashion and scored for a series of 31 cytomorphologic features. The intraclass correlation between diagnostic categories and overall agreement between cytopathologists was statistically evaluated. Results: Aspirates of PTCFA were originally diagnosed as 'negative' (n = 3), 'AUS/FLUS' (n = 7), 'suspicious for a follicular neoplasm' (n = 3), 'suspicious for malignancy' (n = 3), and 'malignant' (n = 1). On masked review, the most common cytomorphologic features of PTCFA were a nonmacrofollicular cytoarchitectural pattern (71%), medium-large cell size (74%), and micronucleoli (79%). Intranuclear pseudoinclusions and a papillary architecture were absent in 85 and 88% of the cases, respectively. Relative to the 2 control groups, the PTCFA cases demonstrated overlapping features between FA and PTC for the majority of the 31 examined cytomorphologic features. Conclusion: PTCFA represent a rare subset of PTC that is difficult to recognize as PTC by FNAB. Most cases exhibit overlapping features between a benign thyroid nodule and conventional PTC, and they are often interpreted as 'AUS/FLUS'.     

Cytologic criteria of cystic papillary carcinoma of the thyroid

OBJECTIVE: To establish differential cytologic criteria between benign and malignant thyroid cysts. STUDY DESIGN: The study was a retrospective, transverse, analytic, comparative one of 3 groups of patients with nonfunctional thyroid nodules subjected to fine needle aspiration biopsy (FNAB) and surgical resection of the lesions, with histologic study as the diagnostic gold standard. Fifteen cases of cystic papillary carcinomas (group 1) with initial false negative diagnoses, 42 goiters accompanied by cystic degeneration (group 2) and 15 noncystic papillary carcinomas (group 3) were studied. Independent variables were age and sex; dependent variables were the presence of tridimensional fragments, papillae, anisonucleosis, nuclear bars, pseudoinclusions, powdery chromatin, cytoplasmic vacuoles, metaplastic cytoplasm, psammoma bodies, autolysis, multinucleated giant cells, spindle cells, colloid, monolayered laminae and macrophages in FNAB specimens. Statistical analysis was performed by central tendency measures and the chi 2 test. RESULTS: The chi 2 test revealed a statistically significant difference between group 2 and the groups with papillary carcinoma based on the presence of tridimensional fragments, anisonucleosis, nuclear bars, pseudoinclusions, powdery chromatin, cytoplasmic vacuoles, metaplastic cytoplasm and autolysis. CONCLUSION: The above cytologic characteristics must be searched for systematically in the FNAB of every cystic lesion of the thyroid to rule out the presence of cystic papillary thyroid carcinoma and to decrease the rate of false negative results.     

Expression of galectin-1 and galectin-3 in human fetal thyroid gland.

High levels of expression of galectin-1 and galectin-3, the beta-galactoside-binding proteins, have been recently described in malignant thyroid tumors but not in adenomas nor in normal thyroid tissue. However, there are no data about the expression of these galectins during fetal thyroid development. In this study we analyzed immunohistochemically the presence of galectin-1 and galectin-3 in human fetal thyroid glands (16-37 weeks of gestation). Weak to moderate cytoplasmic staining for galectin-1 was observed in follicular cells of all fetal thyroids. Galectin-3 could not be detected in thyroid follicular cells of any fetal thyroid investigated. Both galectins were detected in stromal tissue, but staining for galectin-1 was more intense. The absence of galectin-3 in thyroid cells during fetal development suggests that galectin-3 is expressed de novo during malignant transformation of thyroid epithelium, and that galectin-1 could be considered an oncofetal antigen. The results obtained indicated potential roles for galectin-1 and galectin-3 during the investigated period of human fetal thyroid gland development. Both galectins might participate in developmental processes regarding stromal fetal thyroid tissue organization, whereas galectin-1 might have a function in thyroid epithelium maturation.     

Morphometric image analysis of follicular lesions of the thyroid

OBJECTIVE: To determine the role of image morphometry in distinguishing various follicular lesions of the thyroid in cytologic smears. STUDY DESIGN: Archival fine needle aspiration smears of 10 cases each of follicular hyperplasia, follicular adenoma, follicular carcinoma and follicular variant of papillary carcinoma were used for the study. All cases were histopathologically proven. At least 100 random nuclei from each case were subjected to analysis with an image cytometer. Area, convex area, length, width, perimeter, convex perimeter and roundness of nuclei were measured using a 40 x objective (1 pixel = 0.446 micron). RESULTS: ANOVA showed that all the nuclear variables studied were significantly different (P < .05) in follicular hyperplasia as compared to follicular carcinoma and papillary carcinoma. All nuclear variables except roundness were also significantly different (P < .05) between follicular hyperplasia and follicular adenoma. However, between follicular adenoma, follicular carcinoma and papillary carcinoma there was considerable overlap of nuclear morphometric parameters. CONCLUSION: Image morphometry may help to distinguish nonneoplastic follicular lesions (hyperplasia) from neoplastic lesions (adenomas and carcinomas). However, to distinguish benign from malignant follicular lesions, image morphometry might not improve the accuracy of standard cytologic examination.     

Intraoperative imprint cytology of the thyroid gland with computer-assisted morphometric analysis of cell clusters

Imprint preparations were used in addition to frozen sections in the intraoperative diagnosis of 37 cases of benign and malignant lesions of the thyroid gland, including adenomatous goiter, follicular adenoma, follicular carcinoma and papillary carcinoma. In the imprints, the cytologic features specific for carcinoma, as compared with benign lesions, were (1) the folding of the nuclear contour, (2) the increased density of the cytoplasmic matrix and (3) the frequent appearance of cell clusters of larger size. The size and frequency of cell clusters were morphometrically analyzed by a computer image analyzer. There was an increasing number of large clusters, plus the appearance of clusters of more than 300 micron in diameter, in both follicular and papillary carcinoma. In benign lesions, on the contrary, the majority of cells were isolated or in small clusters, the diameter of which never exceeded 300 micron in diameter. These results demonstrate that (1) the imprint cytology of the thyroid gland is useful in making a rapid intraoperative diagnosis and (2) the introduction of computer-assisted quantitative analysis is of practical value in the diagnosis of malignancy.     

Be Aware of the Patient With Benign Follicular Thyroid Lesion Histology and Rising Thyroglobulin Level

Objective: The accurate diagnosis of thyroid follicular/Hürthle cell tumors is challenging and a matter of controversy. We present a series of patients in whom a misclassification of follicular/Hürthle cell thyroid lesions as benign has led to devastating clinical outcomes.Methods: The Thyroid Cancer Registry of Rabin Medical Center was screened for patients with metastatic differentiated thyroid carcinoma (DTC) who had been initially diagnosed with benign follicular lesion between 1974 and 2015 and treated with hemithyroidectomy. Clinical, pathologic, and outcome data were collected from the medical files. Adequate pathology specimens, when available, were re-evaluated.Results: Seven patients met the inclusion criteria. The original pathologic diagnosis was follicular adenoma in 4 patients and Hürthle cell adenoma in 3 patients. Five patients had bone metastases, of whom one also had lung metastases and one, liver metastases. One patient had both cervical and lung metastases, and 1 patient had only meta-static neck lymph nodes. Six patients had a final diagnosis of encapsulated follicular variant of papillary thyroid carcinoma (EFVPTC), and 1 patient was diagnosed as having follicular thyroid cancer metastasis by bone biopsy. In 3 of the patients, capsular invasion was detected retrospectively; only 1 patient had evidence of vascular invasion. All 7 patients had high levels of thyroglobulin at diagnosis of metastatic DTC.Conclusion: Misclassification of follicular thyroid lesions as benign may lead to progressive disseminated DTC. To minimize the clinical risk of misdiagnosis, especially if a thorough evaluation of the specimens by an experienced pathologist is unfeasible, we suggest long-term follow-up of serum thyroglobulin levels.Abbreviations: DTC = differentiated thyroid carcinoma; EFVPTC = encapsulated follicular variant of papillary thyroid carcinoma; FVPTC = follicular variant of papillary thyroid carcinoma; NIFTP = noninvasive follicular thyroid neoplasm with papillary-like nuclear features; PTC = papillary thyroid carcinoma     

Cytoplasmic and serum galectin-3 in diagnosis of thyroid malignancies

In order to address whether galectin-3 in the sera and fine needle aspirates serve as a diagnostic marker distinguishing between benign and malignant thyroid nodules, we developed an enzyme-linked immunosorbent assay. We quantified galectin-3 in fine needle aspirates from a series of 118 patients with thyroid nodules and serum galectin-3 from another series of 46 patients, which were compared with final histology after thyroidectomy. Relative galectin-3 value (ng/mg), defined as galectin-3 concentration (ng/ml) divided by total protein concentration (mg/ml) in fine needle aspirates, was significantly higher in papillary carcinoma than in the other thyroid entities. There was no significant difference in serum galectin-3 level among patients with thyroid nodules and healthy individuals. Accordingly, relative galectin-3 value allows a definitive diagnosis of papillary carcinoma independent of cellular morphology, whereas serum galectin-3 does not serve as a marker for papillary carcinoma.     

Papillary Hyperplastic Nodule: Pitfall in the Cytopathologic Diagnosis of Papillary Thyroid Carcinoma

ObjectiveTo identify the pitfalls of overdiagnosing papillary formation as papillary thyroid carcinoma (PTC) in thyroid cytology specimens.MethodsPatients with papillary hyperplastic nodules who had preoperative fine-needle aspiration biopsy (FNAB) were selected for this study. All patients had been diagnosed as having either PTC or lesions suggestive of PTC on preoperative FNAB. Pathology reports, surgical reports, and cytopathology slides were reviewed and analyzed for demographic data, nature of surgery, and pathologic features.ResultsSix women and 2 men with a mean age of 49 years (range, 16-79 years) were included. The lesion size ranged from 1.0 to 3.5 cm. Four patients were diagnosed as having PTC and 4 as having lesions suspicious for PTC. FNAB specimens were available for review in 6 cases. Surgical pathology slides were reviewed in all cases. When cytologic material was evaluated for the morphologic features that led to the misdiagnosis of PTC by comparing it with FNAB specimens of classic variant of PTC, the specimens from these patients showed follicular cells arranged in short, nonbranching papillae in a background of watery colloid and macrophages. The follicular cells were round and demonstrated oncocytic change with nuclear enlargement, prominent central nucleoli, nuclear chromatin clearing, and intranuclear grooves.ConclusionsCaution should be exercised rendering the diagnosis of PTC on FNAB samples when a thyroid lesion shows papillary configurations and oncocytic cells and if convincing nuclear features of PTC are not present. Furthermore, some morphologic features on thyroid aspiration can help differentiate these cases from true PTC. (Endocr Pract. 2008;14:863-868)     

Comparison of CD15, galectin-3 and HBME-1 expression in follicular thyroid neoplasms

INTRODUCTION: Estimation of malignancy in thyroid follicular neoplasms is a common diagnostic problem, thus revealing of differences in expression of some antigens in both benign and malignant lesions seems to be essential. The aim of this study is to evaluate the immunohistochemical expression of CD15, galectin-3 and HBME-1 in follicular adenomas and carcinomas. MATERIAL AND METHODS: Samples of 38 follicular adenomas (23 "classical", 5 with intracapsular invasion, 10 oncocytic) and 15 follicular carcinomas (9 "classic", 6 oncocytic) were stained immunohistochemically with anti-CD15, galectin-3 and HBME-1. RESULTS: In the whole group we found statistically significant differences in CD15 expression between follicular adenomas and carcinomas. "Classic" follicular carcinomas (without oncocytic tumors) showed stronger CD15 and HBME- 1 expression than "classic" adenomas. Adenomas with intracapsular invasion differed from "classic" adenomas only in HBME-1 expression. In oncocytic tumors the expression of examined antigens was similar. CONCLUSIONS: 1. In the group of nonoxyphilic tumors positive reaction with HBME-1 was more common in adenomas with intracapsular invasion and carcinomas, but positive reaction with anti-CD15--only in carcinomas. We suggest that reactivity with these antibodies could mark malignancy. 2. Oncocytic tumors had similar expression of CD15 and HBME-1 and galectin-3.     

Thyroid Cancer Imaging In Vivo by Targeting the Anti-Apoptotic Molecule Galectin-3

Background

The prevalence of thyroid nodules increases with age, average 4–7% for the U.S.A. adult population, but it is much higher (19–67%) when sub-clinical nodules are considered. About 90% of these lesions are benign and a reliable approach to their preoperative characterization is necessary. Unfortunately conventional thyroid scintigraphy does not allow the distinction among benign and malignant thyroid proliferations but it provides only functional information (cold or hot nodules).The expression of the anti-apoptotic molecule galectin-3 is restricted to cancer cells and this feature has potential diagnostic and therapeutic implications. We show here the possibility to obtain thyroid cancer imaging in vivo by targeting galectin-3.

Methods

The galectin-3 based thyroid immuno-scintigraphy uses as radiotracer a specific ^99mTc-radiolabeled mAb. A position-sensitive high-resolution mini-gamma camera was used as imaging capture device. Human galectin-3 positive thyroid cancer xenografts (ARO) and galectin-3 knockout tumors were used as targets in different experiments in vivo. 38 mice with tumor mass of about 1 gm were injected in the tail vein with 100 µCi of ^99mTc-labeled mAb to galectin-3 (30 µg protein/in 100 µl saline solution). Tumor images were acquired at 1 hr, 3 hrs, 6 hrs, 9 hrs and 24 hrs post injection by using the mini-gamma camera.

Findings

Results from different consecutive experiments show an optimal visualization of thyroid cancer xenografts between 6 and 9 hours from injection of the radiotracer. Galectin-3 negative tumors were not detected at all. At 6 hrs post-injection galectin-3 expressing tumors were correctly visualized, while the whole-body activity had essentially cleared.

Conclusions

These results demonstrate the possibility to distinguish preoperatively benign from malignant thyroid nodules by using a specific galectin-3 radio-immunotargeting. In vivo imaging of thyroid cancer may allow a better selection of patients referred to surgery. The possibility to apply this method for imaging and treatment of other galectin-3 expressing tumors is also discussed.     

Evaluation of HMFG2 and thyroglobulin in the diagnosis of thyroid fine needle aspiration (FNA)

In order to appraise the usefulness of HMFG₂ and thyroglobulin (Tg) as specific markers for the diagnosis of thyroid disease, we studied 63 FNA smears. Cases tested included 30 benign (nine colloid goitres, six cases of Hashimoto's thyroiditis, six Hürthle cell adenomas, nine follicular adenomas) and 33 malignant lesions (nine follicular carcinomas, 12 papillary carcinomas, nine anaplastic carcinomas, three medullary carcinomas). All cases with malignant lesions except the anaplastic carcinomas were positive for HMFG₂. Immunoreactive cells to HMFG₂ were also found in 15 adenomas out of 30 benign cases. Positive Tg reaction was found in benign and malignant thyroid lesions, except six cases of Hashimoto's thyroiditis, nine anaplastic and three medullary carcinomas. The results obtained indicate that morphology paired with immunocytochemistry can usually depict a more specific profile of thyroid lesions for better evaluation of the pathology.     

Telomerase activity in thyroid fine needle aspirates

OBJECTIVE: To study the utility of telomerase activity (TA) detection in thyroid fine needle aspirates (FNAs). STUDY DESIGN: One hundred two thyroid nodules were studied: 70 in FNA samples and 32 in frozen tumors. From among FNA samples, there were 57 nodules of the goiter, 1 adenoma, 7 papillary carcinomas, 1 medullary carcinoma and 1 lymphoma. Three cases of thyroiditis were excluded. The 32 frozen tissue tumors consisted of 5 follicular adenomas, 4 follicular carcinomas and 23 papillary carcinomas. TA was analyzed by Telomerase PCR ELISA (Roche Diagnostics, Indianapolis, Indiana, U.S.A.). RESULTS: TA was negative in the 57 nonneoplastic nodules and 6 follicular adenomas and positive in 3 of 4 follicular carcinomas and 10 of 30 papillary carcinomas. TA sensitivity was 41.4% and specificity 100%. Sensitivity for malignancy was higher (85.7%) in FNAs than in TA. CONCLUSION: TA seems highly specific for neoplasms of the thyroid. Further studies are needed to confirm whether TA detection could contribute to identifying neoplasms when FNAs are inconclusive for malignancy and in cases of scanty material.