Challenge in the Pathological Diagnosis of the Follicular- Patterned Thyroid Lesions.

BACKGROUND: The follicular-patterned thyroid lesions (FPTLs) include hyperplastic nodules (HN), follicular adenoma (FA), non-invasive follicular neoplasm with papillary-like nuclear features (NIFTP), follicular carcinoma (FC), and the follicular variant of papillary carcinoma (FVPTC). Sometimes the pathologists cannot accurately separate these lesions from each others on a histological basis. AIMS: To evaluate the utility of immunohistochemistry in the diagnosis of FPTLs. MATERIALS AND METHODS: Immunohistochemical analysis, incorporating 83 cases of histologically confirmed FPTLs out of which 20 carcinomas, 51 benign FPTLs (38 HN and 13 FA), and 12NIFTP were separated from each others using four immunostains (HBME-1, CK19, Galectin-3, and CD56). RESULTS: We found statistically significantly more frequent expression of HBME-1, CK19, Galectin-3 proteins in carcinomas as compared to benign FPTLs (p = <0.01). HBME-1 and Galectin-3 were the most sensitive markers for the diagnosis of malignant FPTLs (75%). Galectin-3 was the most specific marker for the diagnosis of carcinoma (90.3%). CONCLUSIONS: The histomorphological features remain the cornerstone of the diagnosis of FPTN. Although HBME-1, Galectin-3, and CK19 immunostains have some diagnostic value in the separation of malignant from benign FPTLs, they are variably expressed in the benign and malignant FPTLs. No single immunostain has sufficient sensitivity and specificity and therefore their diagnostic use is controversial. Future studies are mandated to find more reliable markers that can separate between benign and malignant FPTLs.

Periostin expression and its supposed roles in benign and malignant thyroid nodules: an immunohistochemical study of 105 cases.

BACKGROUND: Thyroid 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. METHOD: We 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. RESULTS: Stromal 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. CONCLUSIONS: PON 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.

NTRK fusion analysis reveals enrichment in Middle Eastern BRAF wild-type PTC.

Objective: Fusions involving neurotrophic tyrosine receptor kinase (NTRK) are known oncogenic drivers in a broad range of tumor types. It recently gained attention as a predictor of targeted therapy since selective NTRK inhibitors are now approved in the US and Europe for patients with solid tumors harboring gene fusions. However, estimation of NTRK gene fusion/alteration frequency and its clinicopathological characteristics in papillary thyroid cancer (PTC) is limited, especially in a population with high incidence for PTC like Middle Eastern population. This study aims to characterize the NTRK gene fusion frequency and investigate the utility of pan-Trk immunohistochemistry (IHC) as predictor of NTRK fusion in a large cohort of Middle Eastern PTC. Methods: FISH analysis for NTRK gene fusions and pan-Trk IHC was performed on 315 Middle Eastern PTCs. Correlation of NTRK gene fusion and protein expression with clinicopathological markers and patient outcome were determined. Results: In our cohort, 6.0% (19/315) patients showed NTRK gene fusions and were significantly associated with pediatric PTC (P = 0.0143), lymph node metastasis (P = 0.0428) and BRAF WT tumors (P < 0.0001). Pan-Trk IHC was positive in 9.2% (29/315) of cases and significantly associated with NTRK fusions, with a sensitivity of 73.7% and specificity of 94.9% in this cohort. Conclusions: This study confirms the presence of NTRK fusions in Middle Eastern PTC which is significantly enriched in BRAF WT as well as pediatric age group and proposes the usefulness of IHC to screen for PTC patients with NTRK fusion that might benefit from TRK inhibitors.

AHNAK2 is a novel prognostic marker and correlates with immune infiltration in papillary thyroid cancer: Evidence from integrated analysis.

Papillary thyroid cancer (PTC) is the most prevalent endocrine tumor, and its incidence is still increasing. The mechanisms of PTC dedifferentiation and malignant progression remain unclear. In this study, we identified AHNAK2 as a key gene in PTC by differential expression analysis among four GEO datasets and validated its overexpression profile by data from the Oncomine, TCGA, and HPA databases and IHC staining analysis. AHNAK2 upregulation significantly correlated with advanced grades, stages, and lymph node events. Survival analysis suggested that AHNAK2 overexpression was coupled with poor overall survival. The immune infiltration analysis by TIMER and CIBERSORT indicated that AHNAK2 expression tightly correlated with the infiltration of diverse immune cell types, especially T cell subtypes. In addition, AHNAK2 is correlated with the expression of other conventional key genes of TC, such as PIK3CA, MAPK1, CTNNB1, and SLC5A5. AHNAK2 may be a novel prognostic marker for PTC.

Insulin-like growth factor 1 promotes proliferation and invasion of papillary thyroid cancer through the STAT3 pathway.

BACKGROUND: Papillary thyroid cancer (PTC) is a kind of thyroid cancer. Previous studies showed that insulin-like growth factor-1 (IGF1) plays an important role in tumorigenesis, development, invasion, and metastasis. However, the function of IGF1 in PTC progression remains unclear. METHODS: Seventy-three pairs of PTC tissue specimens and adjacent normal specimens form and normal cell line and PTC cell lines were collected in this study. The immunohistochemistry (IHC) assay was performed to test the expression of IGF1. The RNA isolation and quantitative real-time PCR assays (qRT-PCR assays) and Western blot analysis were used to test mRNA and protein expression. Cell proliferation assay, EdU assay, flow cytometry assay, wound healing assay, and Transwell invasion assay were performed to test cell proliferation, invasion, and apoptosis. RESULTS: We found that the expression of IGF1 in PTC tissue samples was higher than that in adjacent normal specimens and was significantly associated with tumor size, TNM staging, and lymph node metastasis. Furthermore, IGF1 treatment significantly increased cell viability in a dose-dependent manner. EdU assay also demonstrated the effect of IGF1 on the proliferation of BCPAP and TPC1 cells. Moreover, IGF1 treatment effectively increased the invasive capacity of BCPAP and TPC1 cells. More importantly, IGF1 treatment could significantly enhance the phosphorylation of STAT3 in BCPAP and TPC1 cells. Moreover, cryptotanshinone (Cryp) treatment reversed the effect of IGF1 treatment on cell viability and invasion of BCPAP and TPC1 cells. CONCLUSION: Collectively, IGF1 promotes proliferation and invasion of PTC progression through the STAT3 signaling pathway.

Objective analysis of collagen organization in thyroid nodule capsules using second harmonic generation microscopy images and the Hough transform.

Papillary carcinoma is the most prevalent type of thyroid cancer. Its diagnosis requires accurate and subjective analyses from expert pathologists. Here we propose a method based on the Hough transform (HT) to detect and objectively quantify local structural differences in collagen thyroid nodule capsules. Second harmonic generation (SHG) microscopy images were acquired on non-stained histological sections of capsule fragments surrounding the healthy thyroid gland and benign and tumoral/malignant nodules. The HT was applied to each SHG image to extract numerical information on the organization of the collagen architecture in the tissues under analysis. Results show that control thyroid capsule samples present a non-organized structure composed of wavy collagen distribution with local orientations. On the opposite, in capsules surrounding malignant nodules, a remodeling of the collagen network takes place and local undulations disappear, resulting in an aligned pattern with a global preferential orientation. The HT procedure was able to quantitatively differentiate thyroid capsules from capsules surrounding papillary thyroid carcinoma (PTC) nodules. Moreover, the algorithm also reveals that the collagen arrangement of the capsules surrounding benign nodules significantly differs from both the thyroid control and PTC nodule capsules. Combining SHG imaging with the HT results thus in an automatic and objective tool to discriminate between the pathological modifications that affect the capsules of thyroid nodules across the progressions of PTC, with potential to be used in clinical settings to complement current state-of-the-art diagnostic methods.

[Fine-needle aspiration for the diagnosis of lymph node metastasis in papillary thyroid carcinoma].

Objective: To investigate the diagnostic performance of fine-needle aspiration (FNA) cytology for the detection of lateral lymph node metastases in patients with papillary thyroid carcinoma (PTC). Methods: A total of 109 lateral lymph nodes with suspicious metastases from 85 patients were retrospectively subjected to FNAC, fine-needle aspiration thyroglobulin measurement (FNATg), and FNATg/SerumTg measurement. Lymph node pathological results after surgery were taken as the gold standard. Using Mann-Whitney U test, Pearson linear model and ROC curve were used for data analysis. Results: The sensitivity, specificity and accuracy of FNATg for the diagnosis of lateral neck lymph node metastasis were respectively 93.7%, 90.0% and 93.3% and those of FNATg/SerumTg were respectively 89.9%, 90.0% and 93.2% respectively, the threshold values for FNATg and FNATg/SerumTg were 0.925 ng/ml and 1.007, respectively. The sensitivity, specificity and accuracy of FNATg combined with FNAC were respectively 91.0%,93.5% and 94.4%. The existence of thyroid tissue and the expression of serum Tg did not affect the expression of lymph node FNATg. The FNATg cutoff value of 0.925 ng/ml showed the best diagnostic performance in patients with a thyroid gland, while the FNATg/SerumTg cutoff ratio of 14.95 showed the best diagnostic performance in patients without a thyroid gland. The serum TgAb significantly interfered with the expression of FNATg in the lateral neck metastatic lymph nodes (P=0.049). Conclusions: FNATg alone or the combination of FNATg with FNAC are highly reliable in the diagnosis of lateral neck lymph node metastases in patients with PTC. The expression of TgAb may interfere with the accuracy of the diagnostic performance of FNATg.

Expression of activator protein-1 in papillary thyroid carcinoma and its clinical significance.

BACKGROUND: The abnormal expression of activator protein-1(AP-1) has recently been investigated in a variety of tumors. While the relationship between AP-1 and thyroid cancer is poorly studied, our study was to evaluate the protein expression and clinical value of AP-1 in papillary thyroid carcinoma (PTC). METHODS: The expression of AP-1 was examined by immunohistochemistry on paraffin-embedded tissues obtained from PTC and correspondent paracancerous tissues of 82 patients. RESULTS: Compared with paracancerous tissues, AP-1 expression was significantly elevated in PTC tissues and the positive rate was 79.3% (65/82). Our study found a linear trend relationship between the expression of AP-1 and tumor size. However, the differences in AP-1 expression among gender, age, lymph node metastasis, number of lesions, location of the lesion, and extrathyroid invasion are not statistically significant. CONCLUSIONS: The expression of AP-1 plays an important role in the proliferation process of PTC.

BRAFV600E Immunohistochemistry in Papillary Thyroid Carcinomas: Relationship Between Clinical and Morphological Parameters.

OBJECTIVE: To investigate the association of the BRAFV600E mutation with papillary thyroid carcinoma using clinical, morphological and prognostic parameters. We also intend to assess the utility of the BRAFV600E immunohistochemistry and compare it with BRAF polymerase chain reaction (RT-PCR). MATERIAL AND METHOD: We applied BRAFV600E immunohistochemistry in a cohort of 107 papillary carcinomas, 19 adenomas and 13 normal thyroid tissues that was chosen retrospectively between 2011 and 2015. Statistical analysis was based on semiquantitative immunohistochemistry findings. We also applied BRAF RT-PCR in a subgroup of 14 papillary carcinomas, 13 metastatic lymph nodes and 4 adenomas that was chosen randomly. RESULTS: In regard to the comparison of BRAFV600E immunohistochemistry and BRAF RT-PCR, a 3+ nuclear and cytoplasmic immunoexpression was considered 'positive'. The BRAFV600E mutation was most frequently observed in classic variant cases. No mutation was detected in follicular variant cases. The mutational status of the primary tumour and the lymph node metastasis was consistent. A significant relationship of the BRAFV600E mutation was found with prognostic factors such as higher pT stage, classic variant, lymphatic invasion, perineural invasion, lower mitotic index, lack of tumour capsule, intrathyroidal spread and extrathyroidal extension. CONCLUSION: Immunohistochemistry, using the VE1 clone, is a reliable technique for detection of the BRAFV600E mutation. Our results with immunohistochemistry are consistent with a previous effort. In our study, despite the correlation between some pathological prognostic parameters and the BRAFV600E mutation; poor prognosis was found to be irrelevant overall. Morphological parameters seem to be keener than the BRAFV600E mutation. Nevertheless, different series display different results, possibly due to environmental factors. Considering this and the proven success of targeted therapies against the BRAFV600E mutation a thorough assessment would be important.

Primary thyroid biphasic synovial sarcoma and synchronous papillary carcinoma: report of a remarkable case.

Synovial Sarcoma (SS) is the fourth most common soft tissue sarcoma, characterized by translocation t(X;18) (p11.2;q11.2). Although its histological features have been extensively described, this entity is characterized by a wide morphological spectrum so that the recognition can be very challenging at atypical anatomical localization, like the thyroid. We describe a case of a 42-ys-old female patient complaining a cervical swelling due to left intrathyroid nodule, measuring 35 mm in its greatest dimension. A Fine Needle Aspiration Cytology (FNAC) was performed and diagnosis of indeterminate neoplastic lesion, indefinite whether primary or metastatic, was formulated. After complete thyroidectomy, the histological picture of the nodule was characterized by a dual cellular population: several glandular structures composed by columnar cells with clear cytoplasm were embedded in a highly cellular stroma composed of spindle-shaped elements. Immunohistochemistry and molecular biology confirmed the morphological suspicion of SS identifying the fusion transcript SYT-SSX1 and thus ruling out several differential diagnoses which include more common thyroid malignancies. Moreover a synchronous papillary microcarcinoma was detected in the controlateral lobe.This case is noteworthy since it describes the synchronous presence in the thyroid of two completely different malignancies, the first one belonging to the soft tissue neoplasm category and the other one originating from the thyroid follicular epithelium.

The clinical significance of PINX1 expression in papillary thyroid carcinoma.

PIN2/TERF1 interacting telomerase inhibitor 1 (PINX1) is a telomerase inhibitor located on human chromosome 8p23 and also acts as a tumor suppressor in several types of cancers, including breast, gastric, ovarian, and bladder cancer. However, the role of PINX1 expression in papillary thyroid carcinoma (PTC) has not been defined. Therefore, we investigated the role of PINX1 expression in PTC by analyzing the correlation between PINX1 expression and various clinicopathological factors. Immunohistochemistry for PINX1 was performed using a tissue microarray of samples taken from the 160 patients with PTC. We also assessed mRNA and protein expression for PINX1 via quantitative real-time polymerase chain reaction and immunohistochemical analysis. Positive staining for PINX1 was found in 16.3% of PTC cases. PINX1 expression was significantly associated with tumor size, lymph node metastasis, telomerase reverse transcriptase, promoter mutation and recurrence. PINX1 mRNA expression was more pronounced in the recurrent group than in the nonrecurrent group. In addition, results of the binary logistic regression model showed that PINX1 protein expression had a significant influence on recurrence. We concluded that PINX1 expression was associated with several clinicopathological factors and had a significant influence on recurrence in patients with PTC. Therefore, PINX1 expression could be a useful prognostic marker in PTC patients.

Clinicopathological and prognostic significance of SHP2 and Hook1 expression in patients with thyroid carcinoma.

Some thyroid carcinomas (TCs) have an aggressive biological behavior and poor prognosis, and lacking of effective molecular markers is still the main obstacle for clinical stratified diagnosis and treatment of TC. The aim of the study was to discover the clinicopathological and prognostic implications of Src homology region 2-containing protein tyrosine phosphatase 2 (SHP2) and Hook microtubule tethering protein 1 (Hook1) expression in TC. The expression of SHP2 and Hook1 was detected by immunohistochemistry on tissue microarrays from 313 primary TCs who underwent surgery in January 2006 and January 2010 in Zhejiang Cancer Hospital. The χ2 test, Kaplan-Meier method, and Cox proportional-hazards regression models were used to analyze the associations between their expressions and clinicopathological features and prognosis. The expression rates of SHP2 and Hook1 in TC were 57.5% (180/313) and 22.0% (69/313), respectively. SHP2 was positively correlated with Hook1 in TC. SHP2 expression differed significantly by age, histologic variants, maximal tumor diameter, intrathyroidal dissemination, metastases, and disease stage (P < .05). Moreover, patients with high SHP2 expression had reduced risk for death of disease compared with those with low SHP2 expression (hazard ratio, 0.267; 95% confidence interval, 0.105-0.684; P = .006) in univariate analysis, but that multivariate analysis failed to suggest that SHP2 was an independent prognostic factor. Hook1 expression differed significantly by histologic variants, maximal tumor diameter, and intrathyroidal dissemination (P < .05). However, there was no significant correlation between Hook1 expression and outcome in TC (P > .05). Our results suggested that SHP2 may be a favorable indicator of prognosis in TC.