Thy3 subclassification and indeterminate thyroid nodule surgical management

To determine current patterns of care and disease characteristics for patients with thyroid carcinoma, a Patient Care Evaluation Study was initiated in 1996 in the U.S. and Germany. This project addresses ongoing concerns with respect to the diagnostic evaluation and treatment of patients diagnosed with thyroid carcinoma and raises questions concerning how physicians are interpreting current standards and acting on the basis of these recommendations. Patients with primary thyroid carcinoma were entered into a prospective multicenter observational study with free choice of treatment (no control group) between January 1, 1996 and December 31, 1996 in Germany. This resulted in a total of 2537 cases under observation and analysis; 1685 patients had papillary carcinoma (66.4%), 691 had follicular carcinoma (27.2%), 70 had medullary carcinoma (2.8%), and 91 had anaplastic carcinoma (3.6%). The 2376 patients with carcinoma of either papillary or follicular histology were included in the current analysis. The major symptoms reported for patients with papillary and follicular thyroid carcinoma was neck mass (reported in 76% and 79%, respectively) followed by dysphagia (reported in 25% and 27%, respectively), stridor (reported in 9% and 14%, respectively), and neck pain (reported in 7% and 8%, respectively). Greater than 50% of the patients with papillary thyroid carcinoma were reported to have American Joint Committee on Cancer/International Union Against Cancer Stage I disease. Between 37-39% of the follicular carcinoma patients had Stage I and Stage II disease. Only slight differences in the diagnostic approach to patients with papillary or follicular carcinoma were noted. The majority of patients underwent an ultrasound of the thyroid region (78.1%), which was suggestive of carcinoma in only 39% of the cases. A thyroid scan was performed on 76.6% of patients, and the results were suggestive of carcinoma in 44.8% of the individuals. In contrast, fine-needle aspiration biopsy of the thyroid is highly recommended in the current Clinical Practice Guidelines (CPG) but results were obtained in only 27.4% of the patients. Total thyroidectomy without lymph node dissection was the most commonly used surgical procedure in the treatment of patients with papillary and follicular thyroid carcinoma. Only approximately 2% of patients at low risk in the group with Stage I disease were treated with a lobectomy. In 80% of the patients with Stage I papillary thyroid carcinoma and approximately 90% of those patients diagnosed with Stage II, III, and IV disease treating physicians chose to utilize radioiodine as adjuvant treatment after disease-directed surgery. External beam radiation was added to the treatment regimen for many patients diagnosed with Stage III and IV disease (30% in patients with papillary thyroid carcinoma and 33% in patients with follicular thyroid carcinoma). To the authors' knowledge no single effective diagnostic test for thyroid carcinoma currently is available and in the majority of cases a combination of ultrasound, thyroid scan, or fine-needle aspiration biopsy together with the clinical findings (e.g., thyroid mass) led to a diagnosis of carcinoma. The authors suspect that the high prevalence of concomitant pathologic findings such as goiter, even in the healthy population in Germany, reduces the accuracy of all diagnostic test methods and may account for the frequent use of imaging techniques. The majority of patients underwent a total or near-total thyroidectomy. Total thyroidectomy with radical lymph node dissection was used very frequently in those patients with papillary thyroid carcinoma (22%). German physicians tend to surgically treat early stage thyroid carcinoma somewhat more radically than recommended in the CPG. With respect to other treatment options employed as part of the first course of treatment, radioiodine appears to play the most important role. [See commentary o

There are limitations in the diagnosis of thyroid nodules, especially follicular lesions, and their pathogenesis remains unclear. Insulin-like growth factor-1 (IGF-1) has been implicated in tumor cell apoptosis, transformation, invasion, and metastasis; however, its role in thyroid nodules is undetermined. The aim of this study is to investigate the relationship between expression of IGF-1 and thyroid nodule, and evaluate the role of IGF-1 in differential diagnosis and pathogenetic function of benign and malignant thyroid nodules. Sixty-two paraffin-embedded thyroid tissues from patients with thyroid nodules were selected, including 18 follicular adenomas (FA), 17 nodular goiters, 13 papillary thyroid carcinomas (PTC), 2 follicular thyroid carcinomas, and 12 normal controls. IGF-1 and IGF-1R protein and mRNA expression was detected by immunohistochemistry (IHC) and real-time quantitative PCR (qRT-PCR), respectively. Grouping comparisons were employed among the above groups based on the clinical and pathological subtypes. IGF-1 and IGF-1R expression was significantly higher in FA, nodular goiters, and PTC than that in the controls (all P < 0.01). Similarly, IGF-1 mRNA expression was also significantly higher in FA (P < 0.05), nodular goiters (P < 0.01), and PTC (P < 0.01) compared with the controls. IGF-1R mRNA expression was also significantly higher in FA, nodular goiters, and PTC (all P < 0.01) compared with the controls. Compared with FA and nodular goiters, PTC showed significantly higher IGF-1 and IGF-1R protein (P < 0.01, P < 0.05, respectively) and mRNA expression (P < 0.01, P < 0.05, respectively). IGF-1 probably plays an important role in the genesis and development of certain solid cold thyroid nodules, including PTC, nodular goiters, and FA. Detection of IGF-1 and IGF-1R expression in thyroid tissues by IHC or qRT-PCR is hard to distinguish malignant from benign lesions.

Impact of Chronic Lymphocytic Thyroiditis on the Diagnostic and Intraoperative Management of Papillary Thyroid Cancer

Thyroid hyperplasia/multinodular goiter, characterized by cellular and follicular overgrowth, is a very common endocrine condition, resulting in various functional and structural consequences and certain malignant potential. Its genetic background is completely unknown. Given previous genetic and epigenetic data suggesting that RASAL1 might be a thyroid tumor suppressor gene, particularly in follicular thyroid neoplasm, we hypothesized that the RASAL1 gene could play a fundamental role in the development of thyroid hyperplasia/multinodular goiter. To explore the role of the RASAL1 gene in the development of thyroid hyperplasia/multinodular goiter, we developed a novel Rasal1 knockout mouse model using the CRISPR/Cas9 approach and the C57BL/6J zygotes, followed by observing the pathological changes in the thyroid gland of the knockout mice in comparison with the wildtype mice. We successfully created a novel Rasal1 knockout mouse model with establishment of several generations of mice carrying the heterozygous and homozygous knockout of the Ra-sal1 gene at exon 2, which was confirmed by genetic testing and by Western blotting of the Rasal1 protein. All the mice with Rasal1 knockout, whether heterozygous or homozygous, developed grossly visible multinodular goiter with microscopic confirmation of follicular cell hyperplasia, with occasional case showing thyroid cancer. In contrast, only occasional case of aged wild-type mice developed thyroid hyperplasia and no wild-type mice developed thyroid malignancy. These data demonstrate that defect of Rasal1 can cause full and complete development of thyroid hyperplasia/multinodular goiter in mice. Given the striking similarity of thyroid hyperplasia/multinodular goiter in these Rasal1 knockout mice with that in humans, it is plausible to suggest that RASAL1 is a master gene involved in the development and pathogenesis of human thyroid hyperplasia/ multinodular goiter. This project also provides a new genetic knockout mouse model for future study of thyroid neoplasm.

Background: Chromosomal rearrangements leading to gene fusions are a known molecular mechanism of thyroid cancer. ThyroSeq Genomic Classifier (GC) allows detecting most of the known fusion types preoperatively by analyzing thyroid fine-needle aspiration (FNA) samples collected from thyroid nodules, but it also facilitates discovery of novel fusion types. The goal of this study was to evaluate the prevalence and types of known and novel fusions detected in thyroid nodules during routing clinical testing and establish histopathologic and clinical correlations. Design: Overall, 6,800 consecutive thyroid nodules were tested by a targeted next-generation sequencing assay (ThyroSeq v3 GC) using material collected by fine-needle aspiration (FNA). In addition, 17 surgically removed tumors were tested for confirmation of fusion subtype. Surgical pathology and clinical follow-up was obtained when available. Immunohistochemistry was performed on selected cases. Results: Gene fusions were identified in 318 (4.68%) of consecutively tested thyroid nodules. The most common fusion type was THADA/IGF2BP3 detected in 121 (38%) cases, followed by RET/PTC in 52 (16%), NTRK3 in 47 (15%), and PPARG in 47 (15%). Other fusions were found at lower prevalence, including BRAF in 14 (4%), ALK in 9 (3%), THADA/TRA2A in 8 (3%), and NTRK1 in 8 (3%) cases. In addition, 12 (4%) of nodules had rare and novel fusions, including PAX8/GLIS fusions. Presence of PAX8/GLIS fusions was confirmed in resected tumor samples. Surgical pathology information was collected on 49 (16%) positive cases and is ongoing. RET/PTC, NTRK3, NTRK1, and ALK fusions were all diagnosed as classic papillary thyroid carcinoma (PTC) or follicular variant of PTC. All 3 ALK-positive PTC and 5 THADA/IGF2BP3 NIFTP showed strong and diffuse immunoreactivity with ALK and IMP3 antibodies, respectively. THADA/IGF2BP3 was found in noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) (50%), PTC (40%) and follicular thyroid carcinoma (FTC) (10%). PPARG fusions were found in FTC (25%), Hurthle cell carcinoma (25%), PTC (25%) and follicular adenomas (25%). One BRAF fusion (SND1/BRAF) was found in follicular adenoma and all other nodules were PTC. All PAX8/GLIS fusions were characteristic of hyalinizing trabecular tumors. Conclusions: ThyroSeq GC detected gene fusions in approximately 5% of thyroid nodules that underwent FNA. ThyroSeq overall correct call rate for fusions was 94.1%, with variation between specific fusion types. Preoperative detection of fusions in FNA samples assists with diagnosis of thyroid nodules and thyroid cancer and informs patient management.

This experiment was conducted to investigate the dielectric properties of different types of thyroid nodules. Our goal was to find a simple and fast method to detect thyroid diseases at different stages from the dielectric properties of thyroid nodules. We used the open-ended coaxial line method to measure the dielectric permittivities of thyroid tissues from 155 patients at frequencies ranging from 1 to 4000MHz. Tissues that were investigated included normal thyroid tissue and benign and malignant thyroid nodules (nodular goiter, follicular adenoma, papillary carcinoma, and follicular carcinoma), as determined from pathological reports. Differences in dielectric properties were measured between each nodule and the surrounding 1cm of tissue. The analysis results revealed that the dielectric permittivity and conductivity values were positively correlated with the degree of malignancy of the nodule (normal<benign<malignant; all differences P<0.05). This was more obvious at frequencies within 20~70MHz, following the order normal tissue<nodular goiter<follicular adenoma<papillary carcinoma<follicular carcinoma. A significant difference (P<0.05) in dielectric permittivity and conductivity was found when comparing these nodules with the surrounding 1cm of tissue. Normal, benign, and malignant nodules were successfully distinguished from one another, and dielectric permittivity was found to be a more sensitive parameter than conductivity. In particular, different disease types can be distinguished at a stimulation frequency of 20~70MHz, which shows that dielectric properties have application prospects for the detection and diagnosis of cancer. At the same time, the dielectric parameter differences between the surrounding 1cm of tissue and the diseased nodule can distinguish the tumor and its surrounding tissues in real time during surgery to determine the tumor boundary.

Introduction/Objective This study examines molecular results(MR) and surgical follow-up(SFU) of cytologically- indeterminate thyroid nodules. Methods/Case Report Atypia-of-undetermined significance/suspicious-for-follicular-neoplasm cases that underwent Quest/ThyroSeq molecular testing between 2015-2022 were analyzed for MR, SFU and lymph node metastasis(LNM). Results (if a Case Study enter NA) 417 cases(Quest=192, ThyroSeq=225). 59% had SFU. 43% malignancy rate.SFU for Quest(49%): non-neoplastic(NNP)=20%, neoplastic(NP)=80%. MR in these cases:NRAS=48, HRAS=19, BRAF=15, KRAS=8, RET/PTC=3, PAX8=2. SFU: papillary thyroid carcinoma(PTC)=35, non-invasive-follicular-thyroid- papillary-neoplasm with papillary-like nuclear features(NIFTP)=20, thyroid nodular follicular disease(TFND)=18, follicular adenoma(FA)=10, follicular carcinoma(FC)=5, oncocytic carcinoma(OC)=1, lymphocytic thyroiditis(LT)=1. Surgical-molecular correlation(SMC): PTC in 3/3 RET/PTC-mutated, 14/15 BRAF-mutated cases. 1 TFND was BRAF- positive. RAS-mutated category: NIFTP=20,PTC=18,TFND=17,FA=9, OA=5, FC=5, LT=1. In RAS-mutated PTCs, NRAS was most common(n=13), followed by HRAS(n=4) and KRAS(n=1). 2 PAX8-mutated cases showed FA and OC. 9/41 malignant cases, all PTC, had LNM, MR:BRAF=6, HRAS=2, RET/PTC=1.SFU for ThyroSeq(68%): NN=10%, NNP=90%. MR:NRAS=34, copy number alterations(CNAs)=25, HRAS=14, BRAF=13, KRAS=11, gene expression alterations(GEA)=7, THADA+IGF2BP3=7, CNAs Hurthle cell type(HCT)=6, EIF1AX=6, DICER1=4, PAX8- PPARG fusion=4, CNAs+GEA=3, NTRK3=3, TERT=2, RAS+EIF1AX=2, TERT+CNAs=2, EIF1AX=1, EZH1=1, RET/PTC1 fusion=1, ALK=1, BRAF K601E=1,RAS+TERT=1, RAS+TERT+PTEN+EIF1AX=1, TERT+BRAF=1, TERT+EIF1AX=1,TP53+CNAs=1. SFU:PTC=39, NIFTP=31, OA=21, FA=20, papillary microcarcinoma(PMiC)=13, TFND=10, OC=7, LT=6, FC=5, poorly differentiated carcinoma(PdC)=1.10/13 BRAF-mutated cases were PTC, other 3 PMiC. SFU of RAS-mutated cases(n=59):TFND=6, LT=4, NIFTP=19, FA=8, OA=4, PTC=13, PMiC=2, FC=2. RAS mutations in PTC: KRAS=6, HRAS=4, NRAS=3. SFU of CNAs-HCT: OA=3, OC=2, TFND=1. Infrequently detected mutations with SFU of PTC:RET/PTC(1/1), ALK(1/1), RAS+TERT(1/1), TERT+BRAF(1/1), BRAF K601E(1/1), RAS+EIF1AX(1/2). SFU of RAS+TERT+PTEN+EIF1AX:PdC. 11/65 malignant cases, all PTC had LNM:BRAF=5, KRAS=3, CNAs=1, EIF1AX=1, TERT+BRAF=1. Conclusion Substantial proportion of cases with positive MR underwent surgical resection. BRAF-positive and CNAs- HCT correlated with PTC and oncocytic neoplasms, respectively. BRAF-positive PTCs had a higher incidence of LNM compared to wild-type cases(46% vs.18%).

Introduction: A pretherapeutic distinction between benign and malignant thyroid nodules is critical for the clinical management of patients presenting with thyroid nodules. However, certain follicular-patterned lesions, such as adenomatous nodules, follicular neoplasms comprising Follicular Adenoma (FA) and Follicular Carcinoma (FC), as well as the Follicular Variant of Papillary Thyroid Carcinoma (FVPTC), can pose a significant dilemma during pre-therapeutic Fine Needle Aspiration Cytology (FNAC) evaluation. The present (pilot) study explores the possible utility of messenger Ribonucleic Acid (mRNA) and the protein expression of the two relatively less-explored genes, Cyclin D2 (CCND2) and Protein Convertase 2 (PCSK2), in distinguishing various follicular-patterned thyroid lesions and neoplasms by testing these molecular markers initially on histopathological sections. Aim: To assess the RNA and protein expressions of CCND2 and PCSK2 genes in differentiating follicular-patterned thyroid neoplasms. Materials and Methods: This was a cross-sectional analytical study conducted over 6 years, from August 2014 to August 2020, at the Department of Pathology, Jawaharlal Institute of Postgraduate Medical Education and Research (JIPMER), Puducherry, India. Real-Time quantitative Polymerase Chain Reaction (RT-qPCR) along with Immunohistochemistry (IHC) was performed on a total of 75 tissue samples from follicularpatterned thyroid lesions and neoplasms, including 19 Follicular Hyperplasias (FHs), 10 Nodular Goitres (NGs), 17 FAs, 8 FCs, and 12 FVPTCs, along with nine Conventional Papillary Thyroid Carcinomas (CPTCs). After confirming the RNA and protein expression levels in each of these lesions, Immunoreactive Scoring (IRS) was performed to assess their IHC expression. The Kruskal-Wallis and Analysis of Variance (ANOVA) tests were used to analyse the mRNA expression data, and Pearson analysis was conducted to correlate the IHC data between the study groups. A p-value of &lt;0.05 was considered statistically significant. Results: Among the 75 thyroid lesions studied, both NG and FA showed a relatively higher cyclinD2 mRNA expression, with fold changes of 1.21 and 1.46, respectively. This was also reflected in IHC, with moderate nuclear expression observed in these cases. The PCSK2 mRNA expression was similar to that of CCND2, with the only difference noted between FH and FA. On IHC, eight out of 75 cases had positive PCSK2 expression, including five FHs, two FVPTCs, and one FA, while the remaining 67 cases were negative. Conclusion: The CCND2 and PCSK2 genes assessed in the present study, regarding their mRNA and protein expressions, were not found to be of any practical value in distinguishing benign and malignant follicular lesions or neoplasms of the thyroid.

Detection of BRAF Mutations on Direct Smears of Thyroid Fine Needle Aspirates Using the Cell Transfer Technique

Objective To evaluate the diagnostic and prognostic value of BRAF V600E mutation screening of ultrasound-guided fine-needle aspiration (FNA) specimens in patients with thyroid nodule. Methods The BRAF V600E mutation status were assessed in FNA specimens of 104 patients with thyroid nodules before operations. The BRAF mutation status, clinical, and pathology records of the patients were reviewed and the associations between these characteristics and papillary thyroid cancer(PTC) were analyzed. Results Seventy-one PTC and 14 benign thyroid nodules were included in this study. BRAF V600E mutations were found in 57/71(80%) PTC. All benign thyroid nodules had no BRAF V600E mutation. The sensitivity, specificity, positive predictive value and negative predictive value of BRAF V600E mutations in differentiation between PTC and benign thyroid nodules were 80%, 100%, 100% and 50% (P<0.001). In 44 patients with PTC who underwent surgery, the central compartment lymph node metastases and extrathyroidal invasion were not significantly different between BRAF-positive and BRAF-negative PTC(P=0.283 and 0.307). Conclusions BRAF V600E mutation may be a potential tool to facilitate ultrasound in diagnosis of PTC. In patients with PTC, the presence of the BRAFV600E mutation was not significantly associated with prognostic factors. Key words: Ultrasonography; Thyroid neoplasms; Biopsy, fine-needle; BRAF mutation

BackgroundThyroid tumors are often difficult to histopathologically diagnose, particularly follicular adenoma (FA) and follicular carcinoma (FC). Papillary carcinoma (PAC) has several histological subtypes. Periostin (PON), which is a non-collagenous extracellular matrix molecule, has been implicated in tumor invasiveness. We herein aimed to elucidate the expression status and localization of PON in thyroid tumors.MethodWe collected 105 cases of thyroid nodules, which included cases of adenomatous goiter, FA, microcarcinoma (MIC), PAC, FC, poorly differentiated carcinoma (PDCa), and undifferentiated carcinoma (UCa), and immunohistochemically examined the PON expression patterns of these lesions.ResultsStromal PON deposition was detected in PAC and MIC, particularly in the solid/sclerosing subtype, whereas FA and FC showed weak deposition on the fibrous capsule. However, the invasive and/or extracapsular regions of microinvasive FC showed quite strong PON expression. Except for it, we could not find any significant histopathological differences between FA and FC. There were no other significant histopathological differences between FA and FC. Although PDCa showed a similar PON expression pattern to PAC, UCa exhibited stromal PON deposition in its invasive portions and cytoplasmic expression in its carcinoma cells. Although there was only one case of UCa, it showed strong PON immunopositivity. PAC and MIC showed similar patterns of stromal PON deposition, particularly at the invasive front.ConclusionsPON may play a role in the invasion of thyroid carcinomas, particularly PAC and UCa, whereas it may act as a barrier to the growth of tumor cells in FA and minimally invasive FC.

Galectin-3 is a beta-galactoside-binding protein that has been reported to be expressed preferentially in thyroid malignancies. The current study was designed to substantiate this finding further and to establish a presurgical diagnostic modality of differentiating between benign and malignant thyroid neoplasms by analyzing galectin-3 expression in fine-needle aspirates. The expression of galectin-3 was examined immunohistochemically in total of 172 specimens: 45 primary and 20 metastatic papillary carcinomas, 8 primary and 2 metastatic follicular carcinomas, 5 primary and 3 metastatic anaplastic carcinomas, 3 primary medullary carcinomas, 25 follicular adenomas, 3 goiters, and 58 adjacent normal thyroid tissue. Alternatively, epithelial cells were isolated from the fine- needle aspirates of 14 thyroid nodules and subjected to immunoblotting analysis of galectin-3. Immunohistochemical analysis revealed that all thyroid malignancies of follicular cell origin (including papillary, follicular, and anaplastic carcinomas) showed high and diffuse expression of galectin-3, whereas one of the three medullary carcinomas of parafollicular cell origin displayed weaker and focal expression of galectin-3. In contrast, neither benign thyroid adenomas, goiters, nor normal thyroid tissues expressed galectin-3. Immunoblot analysis of the isolated epithelial cells detected galectin-3 in nine thyroid nodules that were proven histologically to be malignant ( eight papillary carcinomas and one follicular carcinoma) after surgical intervention, whereas galectin-3 was not detected in five nodules proven to be benign follicular adenomas. Galectin-3 serves as a marker of thyroid malignancy of follicular cell origin. Analysis of galectin-3 expression in fine-needle aspirates enhances the differential diagnostic accuracy between benign and malignant thyroid neoplasms.

In the thyroid, abnormal growth can be the result of either benign thyroid nodules (BTNs) or differentiated thyroid cancers (DTCs). If the growth is confirmed to be a DTC, surgical intervention, either a partial or total thyroidectomy, is recommended. Although a majority of BTNs do not require treatment, intervention becomes necessary when nodules cause symptoms, enlargement, or a rare suspicion of malignancy. Clinical presentations of symptoms include psychological and aesthetic ones, such as a large lump on the neck, difficulty swallowing, pressure on the neck, and/or voice changes. The most common form of intervention for minimizing the volume of the BTN is surgery. However, due to several drawbacks to surgery and patient ineligibility, minimally invasive techniques such as radiofrequency ablation (RFA) have been recommended. Radiofrequency ablation serves as a minimally invasive non-surgical procedure that has been recognized to decrease the volume of BTNs. In the following case, we present a 50-year-old female patient with a growing multinodular goiter (MNG). A thyroid fine needle aspiration (FNA) biopsy and genetic testing confirmed the diagnosis of thyroid disease with possible malignancies. The nodule was increasing in size, causing discomfort, and possible malignancies were indicated by the FNA results. In order to avoid surgical intervention, the patient chose to undergo RFA, effectively decreasing the size of the BTN and dissipating the symptoms. This case highlights the effectiveness of RFA as a non-surgical alternative for treating benign MNG. Additionally, this case study provides insight into the unique treatment plans available for patients who opt out of surgery.

Background Expression of thyroid-specific proteins such as thyroglobulin is controlled by several transcription factors. Thyroid transcription factor (TTF) 2 is the most recently characterized and has a temporal expression during thyroid embryogenesis suggesting a role in initiating differentiation. Studies on other thyroid-specific genes have shown a gradual loss in differentiation as a tumour progresses, although a good marker to distinguish follicular adenoma from follicular carcinoma is still needed. There is no information on TTF-2 expression in varying thyroid pathologies. Given its central role in thyroid differentiation, reverse transcriptase–polymerase chain reaction (PCR) was used to investigate this in both archival and fresh thyroid tissues and fine-needle aspirates. Methods Thyroid tissue was obtained with informed consent, snap frozen, and total RNA and messenger RNA (mRNA) was extracted. Since TTF-2 has no introns in the coding region, it was necessary to use mRNA. The RNA was reverse transcribed using oligo(dT) and MMV reverse transcriptase. The quality of the complementary DNA (cDNA) was verified by PCR using intron–exon boundary spanning primers for the phosphoglucokinase (PGK) housekeeping gene; a 250-base pair (bp) product is derived from cDNA but a 650-bp product from amplification of contaminant genomic DNA. PCR amplification of TTF-2 used two sets of primers; A + D spans the DNA-binding region and gives a product of 460 bp while primers P + E generate a product of 370 bp in the carboxyl end of the coding region. Products were analysed by agarose gel electrophoresis and compared with a 100-bp ladder. Results A single band of 250 bp was obtained in all 33 thyroid tissue samples but in only three of eight fine-needle aspirates, after 40 cycles, using the PGK primers. Appropriate size products were obtained, after 30 cycles, invariably with both sets of TTF-2 primers, in all 18 benign thyroid nodules of varying pathology, including all five follicular adenomas, and in five of 15 malignant thyroid nodules. Four of five papillary carcinomas and one of seven follicular carcinomas expressed TTF-2; neither of two anaplastic carcinomas and one other carcinoma did not. One of six benign and one of two malignant thyroid nodules expressed TTF-2 on fine-needle aspiration cytology. Conclusion The results suggest loss of TTF-2 expression in poorly differentiated thyroid tumours and that TTF-2 may be helpful in distinguishing follicular adenoma from follicular carcinoma.

Background : Thyroid carcinoma is uncommon in children, but there has been a rising incidence in recent time. This study was undertaken to determine the pattern in Kano. Patients and Methods : Four cases of differentiated thyroid carcinoma (DTC) in children and adolescents seen between October 1997 and September 2005 were retrospectively studied. The parameters studied included the demographic, and clinicopathologic characteristics, and treatment outcome. Results : There were 3 females and 1 male (M: F=1:3), with a mean age of 13.2 years. All the patients presented with asymptomatic thyroid nodule, with cytological diagnosis of malignancy in 3. There were no serious complications after total thyroidectomy. Histological examination confirmed the diagnosis of papillary thyroid carcinoma in 3 patients, and one case of follicular thyroid carcinoma. Two out of the 3 papillary thyroid cancers were multicentric. Follow up was poor, the longest period being one year. Conclusion : DTC in children and adolescence present most commonly as a solitary thyroid nodule. Fine needle aspiration cytology (FNAC) is an important means in preoperative investigations. Total thyroidectomy by experienced thyroid surgeons, has reduced morbidity and mortality. Keywords : solitary thyroid nodule, FNAC, papillary thyroid carcinoma, total thyroidectomy, childhood African Journal of Paediatric Surgery Vol. 2(1) 2005: 20-23