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Abstract Background Thyroid nodules with indeterminate cytological features on fine needle aspiration (FNA) cytology have a 20% risk of thyroid cancer. The aim of the current study was to determine the diagnostic utility of an 8-gene assay to distinguish benign from malignant thyroid neoplasm. Methods The mRNA expression level of 9 genes (KIT, SYNGR2, C21orf4, Hs.296031, DDI2, CDH1, LSM7, TC1, NATH) was analysed by quantitative PCR (q-PCR) in 93 FNA cytological samples. To evaluate the diagnostic utility of all the genes analysed, we assessed the area under the curve (AUC) for each gene individually and in combination. BRAF exon 15 status was determined by pyrosequencing. An 8-gene computational model (Neural Network Bayesian Classifier) was built and a multiple-variable analysis was then performed to assess the correlation between the markers. Results The AUC for each significant marker ranged between 0.625 and 0.900, thus all the significant markers, alone and in combination, can be used to distinguish between malignant and benign FNA samples. The classifier made up of KIT, CDH1, LSM7, C21orf4, DDI2, TC1, Hs.296031 and BRAF had a predictive power of 88.8%. It proved to be useful for risk stratification of the most critical cytological group of the indeterminate lesions for which there is the greatest need of accurate diagnostic markers. Conclusion The genetic classification obtained with this model is highly accurate at differentiating malignant from benign thyroid lesions and might be a useful adjunct in the preoperative management of patients with thyroid nodules.

Abstract Background A large amount of information has been collected on the molecular tumorigenesis of thyroid cancer. A low expression of c-KIT gene has been reported during the transformation of normal thyroid epithelium to papillary carcinoma suggesting a possible role of the gene in the differentiation of thyroid tissue rather than in the proliferation. The initial presentation of thyroid carcinoma is through a nodule and the best way nowadays to evaluate it is by fine-needle aspiration (FNA). However many thyroid FNAs are not definitively benign or malignant, yielding an indeterminate or suspicious diagnosis which ranges from 10 to 25% of FNAs. BRAF mutational analysis is commonly used to assess the malignancy of thyroid nodules but unfortunately it still leaves indeterminate diagnoses. The development of molecular initial diagnostic tests for evaluating a thyroid nodule is needed in order to define optimal surgical approach for patients with uncertain diagnosis pre- and intra-operatively. Methods In this study we extracted RNA from 82 FNA smears, 46 malignant and 36 benign at the histology, in order to evaluate by quantitative Real Time PCR the expression levels of c-KIT gene. Results We have found a highly preferential decrease rather than increase in transcript of c-KIT in malignant thyroid lesions compared to the benign ones. To explore the diagnostic utility of c-KIT expression in thyroid nodules, its expression values were divided in four arbitrarily defined classes, with class I characterized by the complete silencing of the gene. Class I and IV represented the two most informative groups, with 100% of the samples found malignant or benign respectively. The molecular analysis was proven by ROC (receiver operating characteristic) analysis to be highly specific and sensitive improving the cytological diagnostic accuracy of 15%. Conclusion We propose the use of BRAF test (after uncertain cytological diagnosis) to assess the malignancy of thyroid nodules at first, then the use of the c-KIT expression to ultimately assess the diagnosis of the nodules that otherwise would remain suspicious. The c-KIT expression-based classification is highly accurate and may provide a tool to overcome the difficulties in today's preoperative diagnosis of thyroid suspicious malignancies.

Background: Papillary carcinomas with diameters that are less than or equal to 1 cm (thyroid papillary microcarcinoma [mPTC]) are quite common but can carry more risk than previously thought. The proper treatment and management of these lesions is still being debated. Even though fine needle aspiration cytology (FNAC) is considered the best method for the diagnosis of thyroid nodules, its efficacy is still questioned for mPTC. We investigated the role of BRAF gene status in preoperative cytological samples, using manual macrodissection as an additional tool to improve the diagnostic accuracy of mPTC. Methods : DNA was extracted directly from stained FNAC smears of 95 patients including 85 with histological diagnoses of papillary thyroid carcinoma (PTC) ≤1 cm and 10 with goiters. The cytological diagnoses of the 95 cases included the following: 42 samples were suspicious for papillary carcinoma, 38 were PTCs, and 15 were indeterminate lesions. DNA was then extracted from the FNAC slides after performing a 'manual macrodissection' procedure. The BRAFV600E mutational status was determined by sequence analysis in all the patients. Results: In this study, we showed that the BRAFV600E mutation was present with a high frequency in patients with mPTC (74%). The presence of the mutation was independent of the size of the tumor. In our study, the combination of the cytological diagnosis and the molecular analysis was able to identify 82% of all cases of mPTC, with an increase of 37% compared with a morphological diagnosis alone. The morpho-molecular analysis was able to reduce the number of suspicious cases by >70%. All of the goiters had a wild-type BRAF status. Conclusions: The analysis of BRAF mutational status in FNAC obtained from papillary microcarcinomas demonstrates that molecular pathology, combined with morphology and molecular biology is a powerful tool for cytological diagnosis of mPTC. Our results also confirm the data supporting the biological relevance of PTCs with diameters that are ≤1 cm and the importance of 'manual macrodissection' in the molecular analysis of cytological material. [ABSTRACT FROM AUTHOR]

An abstract of the article "Human Papillomavirus (HPV) Genotypes Among HIV-Infected and HIV-Uninfected Women in Mozambiqu," by Massimo Magnano San Lio, Ivo Marchetti, Carla Carrilho, Maria Pia Cioni, Giovanni Guidotti, Cristina Moscatelli, Fabio Taponeco, Elias Suizane F Walle, Ines Zimba and Generoso Bevilacqua is presented.