Query: thyroid immunohistochemistry

title: Hyperplasia; Thyroid Neoplasms; Papillary Carcinoma Thyroid; Immunohistochemistry.

title: Comparison of Immunohistochemistry and Direct Sequencing Methods for Identification of the BRAFV600E Mutation in Papillary Thyroid Carcinoma
abstract: BackgroundBRAFV600E mutation is the most common somatic variant in papillary thyroid carcinoma (PTC) and is associated with aggressive prognostic factors. The conventional detection method for BRAF mutations is polymerase chain reaction followed by Sanger sequencing. Recently, an immunohistochemistry (IHC) method using a BRAFV600E specific antibody (VE1) has been developed and widely adopted in the clinics; however, there is a lack of evidence regarding the comparability of the IHC and Sanger sequencing methods.MethodsOur institution began using the BRAFV600E IHC test in January 2013. We retrospectively analyzed 697 samples that were tested using both the IHC and sequencing methods, and evaluated their concordance.ResultsBRAF mutation was detected in 90.0% (627/697) of samples using IHC and 83.4% (581/697) of samples using direct sequencing. The diagnostic parameters of IHC compared with Sanger sequencing were as follows: 100% sensitivity (581/581) 60.3% specificity (70/116) 92.7% positive predictive value (581/627) and 100% negative predictive value (70/70) No false negative results were recorded using IHC. The overall concordance rate between the two methods was 93.4% (651/697) Discordant results were found in 46 samples (6.6% 29 of which were from cases with small tumors 6 mm) 8 were from cases with low tumor cellularity, and 9 were specimens yielding low quality DNA.ConclusionsIHC using the VE1 antibody is a reliable and highly sensitive method for detecting the BRAFV600E mutation in classic PTC.

title: Comparison of Immunohistochemistry and Direct Sanger Sequencing for Detection of the BRAFV600E Mutation in Thyroid Neoplasm
abstract: The BRAFV600E mutation is the most common genetic alteration identified in papillary thyroid carcinoma (PTC) Because of its costs effectiveness and sensitivity, direct Sanger sequencing has several limitations. The aim of this study was to evaluate the efficiency of immunohistochemistry (IHC) as an alternative method to detect the BRAFV600E mutation in preoperative and postoperative tissue samples.  We evaluated 71 patients who underwent thyroid surgery with the result of direct sequencing of the BRAFV600E mutation. IHC staining of the BRAFV600E mutation was performed in 49 preoperative and 23 postoperative thyroid specimens.  Sixty two patients (87.3% had PTC, and of these, BRAFV600E was confirmed by direct sequencing in 57 patients (91.9% In 23 postoperative tissue samples, the BRAFV600E mutation was detected in 16 samples (70% by direct sequencing and 18 samples (78% by IHC. In 24 fine needle aspiration (FNA) samples, BRAFV600E was detected in 18 samples (75% by direct sequencing and 16 samples (67% by IHC. In 25 core needle biopsy (CNB) samples, the BRAFV600E mutation was detected in 15 samples (60% by direct sequencing and 16 samples (64% by IHC. The sensitivity and specificity of IHC for detecting the BRAFV600E mutation were 77.8% and 66.7% in FNA samples and 99.3% and 80.0% in CNB samples.  IHC could be an alternative method to direct Sanger sequencing for BRAFV600E mutation detection both in postoperative and preoperative samples. However, application of IHC to detect the BRAFV600E mutation in FNA samples is of limited value compared with direct sequencing.

title: Ectopic Thyroid Tissue: Immunohistochemistry and Molecular Analysis
abstract: Ectopic thyroid tissue is rare and controversial. Some experts consider it to always be metastatic thyroid carcinoma, whereas others consider it benign as long as it is restricted to few follicles without cytoarchitectural features of papillary thyroid carcinoma. Immunohistochemistry (IHC) and molecular studies have not yet been performed to further characterize this entity. We retrospectively searched our pathology files for all ectopic thyroid inclusions and reviewed clinicopathologic characteristics and concurrent thyroid pathologic findings. We identified 8 cases from 7 patients. Ectopic thyroid tissue was present in the following locations: neck soft tissue: 3, thymus: 2, neck lymph nodes: 2, perihilar soft tissue: 1. All patients had histologically benign thyroid specimens. BRAFV600E (VE1) IHC, HBME 1 IHC, galectin 3 IHC, BRAFV600E allele specific polymerase chain reaction (PCR) and NRAS/KRAS pyrosequencing were performed. To assess the sensitivity and specificity of BRAFV600E IHC compared with PCR; we tested 13 cases of primary and metastatic papillary and follicular thyroid carcinomas. All the ectopic cases were HBME 1, galectin 3, BRAFV600E (IHC, PCR) and NRAS/KRAS mutation negative (specificity=100% Compared with PCR, BRAF IHC had 89% sensitivity and 100% specificity. Lack of common carcinoma associated mutations supports benign nature of this entity. BRAF, HBME 1, and galectin 3 IHC are accurate and helpful when not enough tissue is available for molecular studies. IHC and molecular studies are more helpful than morphology alone in identifying benign thyroid rests.

title: Evaluation of Diagnostic Utility of Immunohistochemistry Markers of TROP 2 and HBME 1 in the Diagnosis of Thyroid Carcinoma
abstract: The diagnosis of thyroid tumors is based on histologic features, but the distinction between benign and malignant thyroid lesions is somehow difficult, especially in lesions with a follicular pattern. Thus, ancillary studies, such as immunohistochemistry (IHC) may be helpful. In this study, we aimed to evaluate the diagnostic value of 2 IHC markers, TROP 2 and HBME 1, in the diagnosis of thyroid cancers.  A total of 102 cases of thyroid lesions, including papillary thyroid carcinoma (classic variant) (29 cases) follicular variant of papillary thyroid carcinoma (21 cases) multinodular goiter (22 cases) follicular adenoma (24 cases) and follicular carcinoma (6 cases) were selected. The hematoxylin eosin slides were reviewed for confirmation of diagnosis, and IHC examination for TROP 2 and HBME 1 was performed.  HBME 1 had 84% sensitivity and 98% specificity with a positive predictive value (PPV) of 98% and a negative predictive value (NPV) of 83% TROP 2 had 93% sensitivity and 74% specificity with a PPV of 81% and an NPV of 90% in malignant thyroid lesions.  IHC panel consisting of TROP 2 and HBME 1 can be used in equivocal follicular patterned lesions for the diagnosis of thyroid carcinomas.

title: Immunohistochemistry as an accurate tool for evaluating BRAF V600E mutation in 130 samples of papillary thyroid cancer
abstract: BRAFV600E mutation has been investigated by immunohistochemistry and has shown high sensitivity and specificity. We aim to investigate the accuracy of immunohistochemistry versus molecular testing of BRAFV600E in papillary thyroid cancer using a large number of polymerase chain reaction positive BRAFV600E papillary thyroid cancer tissues.  We stained 130 formalin fixed papillary thyroid cancer specimens using the VE1 antibody: 100 BRAFV600E positive and 30 BRAFV600E negative confirmed by PCR. The sensitivity, specificity, and predictive values of the antibody were assessed.  Immunohistochemistry of BRAFV600E showed 98.0% sensitivity, 93.3% specificity, and positive and negative predictive values of 98.0% and 93.3% respectively. Of 100 patients with BRAFV600E PCR positive samples, 97 (97.0% had cytoplasmic weak (4.0% moderate (17.0% and strong (76.0% immunostaining. In BRAFV600E PCR negative samples, cytoplasmic staining was not detected in 93.3% (28/30) of papillary thyroid cancer tissues. The receiver operating characteristic curve demonstrated a high validity and comparable immunohistochemistry method (area under the curve 98.8% compared with PCR testing.  The use of VE1 immunohistochemistry for the detection of BRAFV600E in papillary thyroid cancer tissues is a clinically applicable method with high specificity, sensitivity, and positive and negative predictive values. The reliable use of BRAFV600E immunohistochemistry should promulgate the routine use of this method for BRAFV600E detection in papillary thyroid cancer tissues.

title: TROP 2 immunohistochemistry: a highly accurate method in the differential diagnosis of papillary thyroid carcinoma.
abstract: We aimed to evaluate the diagnostic utility of the novel immunohistochemical marker TROP 2 on thyroid specimens (226 tumours and 207 controls) Whole slide immunohistochemistry was performed and scored by automated digital image analysis. Non neoplastic thyroid, follicular adenomas, follicular carcinomas, and medullary carcinomas were negative for TROP 2 immunostaining. The majority of papillary thyroid carcinoma (PTC) specimens (94/114, 82.5% were positive for TROP 2; however, the pattern of staining differed significantly between the histopathological variants. All papillary microcarcinomas (mPTC) PTC classic variant (PTC cv) and tall cell variant (PTC tcv) were TROP 2 positive, with mainly diffuse staining. In contrast, less than half of the PTC follicular variant specimens were positive for TROP 2, with only focal immunoreactivity. TROP 2 could identify PTC cv with 98.1% sensitivity and 97.5% specificity. ROC curve analysis found that the presence of >10% of TROP 2 positive cells in a tumour supported a diagnosis of PTC. The study of intratumoural heterogeneity showed that low volume cytological samples of PTC cv could be adequately assessed by TROP 2 immunostaining. The TROP 2 H score (intensity multiplied by proportion) was significantly associated with PTC variant and capsular invasion in encapsulated PTC follicular variant (p<0.001) None of the baseline (age, gender) and clinical (tumour size, nodal disease, stage) parameters were correlated with TROP 2 expression. In conclusion, TROP 2 membranous staining is a very sensitive and specific marker for PTC cv, PTC tcv, and mPTC, with high overall specificity for PTC.

title: Immunohistochemistry of thyroid gland carcinomas: clinical utility and diagnostic pitfalls
abstract: There are several settings in which immunohistochemistry could be employed in thyroid pathology. Ancillary immunohistochemistry can aid in differentiating tumour types and has also been used to support a diagnosis of malignancy in equivocal follicular lesions. Theoretically, immunostains could serve as prognostic markers as well. Here, we focus on the role of immunohistochemistry as a diagnostic tool mainly in less well differentiated carcinomas, to confirm cell lineage. In this setting, it is important to perform a panel of immunostains and interpret them in the context of the tumour morphology and the clinical picture, since staining patterns can overlap with other non thyroid tumour types. We also address the controversial use of immunostains to separate malignant from benign follicular lesions. Lastly, the potential for immunohistochemistry as prognostic markers will be considered. This review emphasizes the application of immunohistochemistry to thyroid histopathology rather than cytology.

title: Application of immunohistochemistry in thyroid pathology.
abstract: Accurate classification of follicular patterned thyroid lesions is not always an easy task on routine surgical hematoxylin eosin stained or cytologic fine needle aspiration specimens. The diagnostic challenges are partially due to differential diagnostic criteria that are often subtle and subjective. In the past decades, tremendous advances have been made in molecular gene profiling of tumors and diagnostic immunohistochemistry, aiding in diagnostic accuracy and proper patient management.  To evaluate the diagnostic utility of the most commonly studied immunomarkers in the field of thyroid pathology by review of the literature, using the database of indexed articles in PubMed (US National Library of Medicine) from 1976 2013.  Literature review, authors' research data, and personal practice experience.  The appropriate use of immunohistochemistry by applying a panel of immunomarkers and using a standardized technical and interpretational method may complement the morphologic assessment and aid in the accurate classification of difficult thyroid lesions.

title: Immunohistochemistry with the anti BRAF V600E (VE1) antibody: impact of pre analytical conditions and concordance with DNA sequencing in colorectal and papillary thyroid carcinoma
abstract: The most common of all activating BRAF mutations (T1799A) leads to a substitution of valine (V) to glutamic acid (E) at the position 600 of the amino acid sequence. The major goal of this study was to compare detection of the BRAF V600E mutation by DNA sequencing with immunohistochemistry (IHC) using the anti BRAF V600E (VE1) antibody. Archival formalin fixed, paraffin embedded tissues from 352 patients with colon adenocarcinoma (n 279) and papillary thyroid carcinoma (n 73) were evaluated for the BRAF V600E mutation by sequencing and IHC. The discordant cases were re evaluated by repeat IHC, SNaPshot and next generation sequencing (NGS) Furthermore, the effect of pre analytical variables on the utility of this antibody was evaluated in two xenograft mouse models. After resolving 15 initially discordant cases, 212 cases were negative for the BRAF V600E mutation by IHC. Of these, 210 cases (99.1% were also negative by sequencing and two cases (0.9% remained discordant. Of the 140 cases that were IHC positive for BRAF V600E, 138 cases were confirmed by sequencing (98.6% and two cases remained discordant (1.4% Overall, the negative predictive value was 99.1% positive predictive value 98.6% sensitivity 98.6% specificity 99.1% and overall percentage agreement 98.9% (348/352 cases) Tissue fixation studies indicated that tissues should be fixed for 12 24 h within 2 h of tissue collection with 10% neutral buffered formalin.