Utility of immunohistochemical markers in differentiating benign from malignant follicular-derived thyroid nodules

Utility of the Growth Differentiation Factor-15 in the Differential Diagnosis of Follicular-Patterned Lesions of the Thyroid on Cytopathologic and Histopathologic Samples

Background Follicular-patterned lesions are a major gray zone in thyroid cytopathology. The recently introduced 2022 World Health Organization (WHO) classification emphasizes the importance of genetic alterations in thyroid neoplasms with the introduction of certain newer terminologies that are expected to cause remarkable changes in cytopathologic and histopathologic reporting. Although molecular assays such as the Afirma gene expression classifier and the ThyroSeq are already in use, there has been an ongoing search for further reliable molecular markers. The growth differentiation factor-15 (GDF-15) is one among them. This study aimed to determine the diagnostic utility of GDF-15 mRNA expression in frozen tissue and fine-needle aspiration (FNA) samples from follicular-patterned thyroid lesions and neoplasms. Methodology The real-time quantitative polymerase chain reaction was performed on 75 frozen tissue and FNA samples each from 19 cases of follicular thyroid hyperplasia (FTH), 10 nodular goiters (NGs), 17 follicular thyroid adenomas (FTAs), eight follicular thyroid carcinomas (FTCs), 12 follicular variant of papillary thyroid carcinomas (FVPTCs), and nine classic papillary thyroid carcinomas (CPTCs) that were diagnosed according to the 2017 WHO classification of thyroid neoplasms. The GDF-15 mRNA expression in all these cases was assessed and compared with the control thyroid tissue samples. One-way analysis of variance and the Kruskal-Wallis test were performed using GraphPad Prism 8 software to determine the significance of differences in the GDF-15 mRNA levels among various thyroid lesions. Results A higher GDF-15 mRNA expression was noted in the malignant thyroid neoplasms including FTC, FVPTC, and CPTC in comparison to FTA, with a fold change between the malignant and benign groups being more than 244.18 times. A difference in the fold change was noted between FTH and FTA with an increase in GDF-15 mRNA level in the latter, which was statistically not significant. Conclusions The fact that GDF-15 mRNA was studied both on fine-needle aspiration cytologic and the frozen tissue material and that the majority of the lesions studied were follicular-patterned establishes the GDF-15 as a potential marker not only for diagnosing malignant thyroid neoplasms of the follicular epithelium but also in distinguishing benign and malignant follicular-patterned neoplasms of the thyroid.

Immunohistochemical Expression of HBME-1 and TROP-2 in Some Follicular-Derived Thyroid Lesions

BACKGROUND AND OBJECTIVES

Detecting thyroid tumors depends on histologic characteristics. However, distinguishing malignant from benign thyroid abnormalities may be challenging and contentious, particularly in tumors with a follicular appearance. Therefore, immunohistochemistry might be useful and essential. Immunohistochemical biomarkers, such as human trophoblast cell surface antigen (TROP) and Hector Battifora Mesothelial-1 (HBME-1), have helped diagnose thyroid cancers. In addition, mesothelial cells have an antigen called HBME-1 on their membranes, but its role is unclear. Thyroid epithelial neoplasms have lately been studied, and TROP-2 is a helpful marker of these tumors. Recently, researchers have explored HBME-1 upregulation in benign and malignant thyroid tumors. This research aimed to show that the immunohistochemical biomarkers TROP-2 and HBME-1 might be employed to distinguish malignant from benign follicular-derived thyroid lesions.

MATERIALS AND METHODS

The research consisted of 50 specimens of various follicular thyroid lesions. From October 2018 to March 2021, blocks of follicular thyroid lesions and clinical information were collected from the Pathology Departments of Al-Azhar University Hospitals. Additionally, the HBME-1 and TROP-2 antigens were stained immunohistochemically.

RESULTS

Expression of TROP-2 along with HBME-1 distinguished benign from malignant follicular-derived thyroid lesions with respective sensitivities of 74.2 and 87.1% and specificities of 84.2 and 78.9%. Furthermore, positive HBME-1 expression was significantly less prevalent in benign lesions (15.8%) than in malignant lesions (74.2%) (P-value <0.001). Moreover, positive TROP-2 expression was significantly lower in benign lesions (21.1%) than in malignant lesions (87.1%) (P-value <0.001). The P value of <0.001 indicated an extremely strong positive correlation between HBME-1 and TROP-2 expression across all instances investigated.

CONCLUSION

With high sensitivity and specificity, both HBME-1 and TROP-2 are beneficial in identifying thyroid cancer, particularly papillary carcinoma, and separating malignant follicular-derived thyroid lesions from benign ones.

Immunohistochemistry in the pathologic diagnosis and management of thyroid neoplasms

The use of immunohistochemistry cannot be underestimated in the everyday practice of thyroid pathology. It has evolved over the years beyond the traditional confirmation of thyroid origin to molecular profiling and the prediction of clinical behavior. In addition, immunohistochemistry has served to implement changes in the current thyroid tumor classification scheme. It is prudent to perform a panel of immunostains, and the immunoprofile should be interpreted in light of the cytologic and architectural features. Immunohistochemistry can also be easily performed in the limited cellularity specimen preparation generated from thyroid fine-needle aspiration and core biopsy; however, it will require laboratory validation of immunostains specific to these preparations to avoid diagnostic pitfalls. This review discusses the application of immunohistochemistry in thyroid pathology with a focus on limited cellularity preparations.

Cytokeratin 19 (CK19) expression by thyroid neoplasms in a Nigerian tertiary health centre

Introduction

despite the observed appreciable sensitivity and specificity of the use of CK19 in predicting thyroid malignancies, there is still a paucity of information about its uses in Nigeria. Current information across the world is also scarce. This study was to review the histopathological diagnosis of thyroid neoplasms seen in Obafemi Awolowo University Teaching Hospital Complex (OAUTHC), Ile Ife, using cytokeratin 19 immunohistochemical marker.

Methods

a retrospective study of fifty-six cases of thyroid neoplasm seen over a period of twenty years was conducted. The tissue samples were subjected to immunohistochemical staining for CK19 using monoclonal antibodies. The expression of the markers on the various thyroid neoplasms was assessed histologically.

Results

the expression of CK19 was significantly higher in malignant thyroid neoplasms compared to benign neoplasms (p<0.05). The sensitivity and specificity for cytokeratin 19 were 90.0% and 75.0% respectively.

Conclusion

diffuse immunohistochemical expression of CK19 is a strong indicator of thyroid malignancy. This biomarker can help in the diagnosis of thyroid neoplasms especially those with incomplete or equivocal histomorphology features.

Scoring System and Diagnosis of Papillary Thyroid Carcinoma Using Human Bone Marrow Endothelium Marker-1, Cytokeratin 19, and Galectin-3

Background

The increasing incidence of papillary thyroid carcinoma (PTC) and the inadequacy of routine histologic examination in its diagnosis necessitate the application of ancillary studies like immunohistochemistry. This research aimed to investigate the scoring system and diagnosis of PTC with cytokeratin 19 (CK19), human bone marrow endothelium marker-1 (HBME-1), and galectin-3.

Methods

This experimental laboratory study was performed at Babol University of Medical Sciences, Mazandaran, Iran from April 2017 to March 2019. Neoplastic and nonneoplastic tissue samples of 100 cases with a diagnosis of PTC were selected by convenience sampling. CK19, HBME-1, and galectin-3 immunohistochemistry markers were used on tissue samples. Analysis was performed using the t test and the chi-square test, as well as the receiver operator characteristic (ROC) curve (significance level P < 0.05).

Results

The CK19 staining was observed in all 100 (100%) non-neoplastic tissues, but HBME-1 and galectin-3 were positive in 36 (36%) and 14 (14%) of non-neoplastic tissues, respectively. The intensity scores of all the markers and their total had significantly different means in PTC and non-neoplastic tissues (P < 0.001). A significant difference was observed between the total score of each marker and the total score of their combination (P < 0.001). The combination of all 3 markers with an 11.5 0 cut-off for the total score showed the most sensitive (0.99) and specific (1.00) results.

Conclusion

Interpreting CK19, HBME-1, and galectin-3 with the aid of the proposed scoring system was fruitful. HBME-1 and galectin-3 can be used individually or in combination for the diagnosis of PTC.

American Head and Neck Society Endocrine Surgery Section and International Thyroid Oncology Group consensus statement on mutational testing in thyroid cancer: Defining advanced thyroid cancer and its targeted treatment

BACKGROUND

The development of systemic treatment options leveraging the molecular landscape of advanced thyroid cancer is a burgeoning field. This is a multidisciplinary evidence-based statement on the definition of advanced thyroid cancer and its targeted systemic treatment.

METHODS

An expert panel was assembled, a literature review was conducted, and best practice statements were developed. The modified Delphi method was applied to assess the degree of consensus for the statements developed by the author panel.

RESULTS

A review of the current understanding of thyroid oncogenesis at a molecular level is presented and characteristics of advanced thyroid cancer are defined. Twenty statements in topics including the multidisciplinary management, molecular evaluation, and targeted systemic treatment of advanced thyroid cancer are provided.

CONCLUSIONS

With the growth in targeted treatment options for thyroid cancer, a consensus definition of advanced disease and statements regarding the utility of molecular testing and available targeted systemic therapy is warranted.

The Combined Utility of HBME-1 and Galectin-3 Immunohistochemistry and BRAF V600E Mutations in the Diagnosis of Papillary Thyroid Carcinoma

Newer diagnostic modalities have revolutionized the pathologist’s approach to diagnosing thyroid malignancies. Molecular characterization of these malignancies has helped circumvent common morphologic diagnostic difficulties by integrating their genotypic, phenotypic, and immunohistochemical features. BRAF V600E mutation has been characterized as highly specific for thyroid carcinoma, especially papillary thyroid carcinoma (PTC); human bone marrow endothelial marker-1 (HBME-1) and galectin-3 are also such markers that are highly specific for PTC. We propose to study HBME-1 and galectin-3 expression and BRAF V600E mutation in thyroid neoplasms and do a comparative analysis to determine whether there is a correlation between BRAF V600E expression and that of HBME-1 and galectin-3. We further propose to analyze the individual and combined diagnosed utility of the above-mentioned ancillary diagnostic techniques.

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.

Application of biomarkers in the diagnosis of uncertain samples of core needle biopsy of thyroid nodules

Core needle biopsy (CNB) is now more frequently used for the preoperative diagnosis of thyroid nodules. Based on morphology alone, 5–20% of CNB samples cannot be determined as malignant or benign. Compared to fine-needle biopsy (FNB), samples collected by CNB are more accessible for various tests. Therefore, studying biomarkers’ application in distinguishing uncertain CNB samples of thyroid nodules is a practical need. Patients of thyroid nodules with both CNB and matched resected specimens were reviewed. Cases classified as indeterminate lesions, follicular neoplasms, and suspicious for malignancy were retrieved. All CNB samples were stained by immunohistochemistry (IHC) using antibodies against CK19, galectin-3, HBME-1, and CD56 and detected by next-generation sequencing (NGS) using an OncoAim® thyroid cancer multigene assay kit (Singlera Genomics) that detected 26 genes. Taking the resected specimens’ classification as the gold standard, the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), accuracy of a single biomarker, and various combinations for discriminating malignancy from benignity were calculated. The sensitivity, specificity, PPV, NPV, and accuracy for preoperative malignancy evaluation were as follows. In the cohort of non-follicular-neoplasm-lesions (non-FN-lesion), they were 95.16%, 53.85%, 90.77%, 70.00%, and 88.00% for CK19; 95.16%, 38.46%, 88.06%, 62.50%, and 85.33% for galectin-3; 77.42%, 76.92%, 94.12%, 41.67%, and 58.00% for HBME-1; 66.13%, 100.00%, 100.00%, 38.24%, and 72.00% for CD56; 90.32%, 92.31%, 98.25%, 66.67%, and 90.67% for NGS; and 88.71%, 92.30%, 98.21%, 63.16%, and 89.33% for integrated IHC. In the cohort of follicular neoplasms (FN), they were 30.43%, 77.77%, 77.77%, 30.43%, and 43.75% for CK19; 73.91%, 66.67%, 85.00%, 50.00%, and 71.88% for galectin-3; 26.09%, 88.89%, 85.71%, 32.00%, and 43.75% for HBME-1; 26.09%, 100.00%, 100.00%, 34.62%, and 46.88% for CD56; 52.17%, 88.89%, 92.31%, 42.11%, and 62.50% for NGS; 82.61%, 66.67%, 86.36%, 60.00%, and 78.13% for integrated IHC; and 100%, 66.67%, 88.46%, 100%, and 90.63% for integrated IHC-NGS. The application of biomarkers in distinguishing uncertain CNB samples of thyroid nodules is available and capable. CD56 negative or NGS positive suggests malignancy strongly for both FN and non-FN-lesion, which may be used as a “rule in” tool. The negative predictive value of the integrated IHC and the integrated IHC-NGS implies a high possibility to be benign for non-FN-lesion and FN separately, which can work as a “rule out” tool. Considering the balance of specificity and sensitivity, NGS is the best for non-FN-lesion and the integrated IHC-NGS is the best for FN.

Diagnostic and prognostic impact of cytokeratin 19 expression analysis in human tumors: a tissue microarray study of 13,172 tumors

To evaluate cytokeratin 19 (CK19) expression in normal and cancerous tissues, 15,977 samples from 122 tumor types and 608 samples of 76 normal tissue types were analyzed by immunohistochemistry (IHC). In normal tissues, CK19 expression occurred in epithelial cells of most glandular organs but was strictly limited to the basal cell layer of nonkeratinizing squamous epithelium and absent in the skin. CK19 expression in ≥90% of cases was seen in 34% of the tumor entities including the adenocarcinomas of the pancreas (99.4%), colorectum (99.8%), esophagus (98.7%), and stomach (97.7%), as well as breast cancer (90.0%-100%), high-grade serous (99.1%) or endometrioid (97.8%) ovarian cancer, and urothelial carcinoma (92.6%-100%). A low CK19 positivity rate (0.1-10%) was seen in 5 of 122 tumor entities including hepatocellular carcinoma and seminoma. A comparison of tumor versus normal tissue findings demonstrated that upregulation and downregulation of CK19 can occur in cancer and that both alterations can be linked to unfavorable phenotypes. CK19 downregulation was linked to high grade (p = 0.0017) and loss of estrogen receptor- and progesterone receptor-expression (p < 0.0001 each) in invasive breast carcinoma of no special type. CK19 upregulation was linked to nodal metastases in neuroendocrine tumors and papillary thyroid carcinomas (p < 0.05 each) and to poor grade in clear cell renal cell carcinoma (p < 0.05). CK19 upregulation was particularly common in squamous cell carcinomas. We concluded that CK19 IHC might separate primary liver cell carcinoma from liver metastases, seminoma from other testicular tumors, and helps in the detection of early neoplastic transformation in squamous epithelium.

HBME1 and CK19 expression in non-invasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) vs other follicular patterned thyroid lesions

BACKGROUND

Thyroid neoplasms with follicular architecture can have overlapping morphologic features and pose diagnostic confusion among pathologists. Various immunohistochemical stains have been investigated as potential diagnostic markers for PTC, among which HBME1 and CK19 have gained popularity. Non-invasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) poses similar diagnostic challenges with interobserver variability and is often misdiagnosed as adenomatoid nodule or follicular adenoma. This study aims to evaluate expression of HBME1 and CK19 in NIFTPs in comparison to other well-differentiated thyroid neoplasms and benign mimickers.

METHOD

Seventy-three thyroid cases diagnosed over a period of 3 years at Methodist University Hospital, Memphis, TN, USA, were included in this study: 9 NIFTP; 18 papillary thyroid carcinoma (PTC); 11 follicular variant of papillary thyroid carcinoma, invasive (I-FVPTC); 24 follicular adenomas (FA); and 11 multinodular goiters/adenomatoid nodules (MNG). A tissue microarray (TMA) was constructed and HBME1 and CK19 immunohistochemistry was performed.

RESULTS

77.8% of NIFTPs, 88.9% of PTCs, 81.8% of I-FVPTCs, 16.7% of FAs, and 18.2% of MNGs showed HBME-1 expression. 66.7% of NIFTPs, 83.3% of PTCs, 81.8% of I-FVPTCs, 33.3% of FAs, and 45.4% of MNGs expressed CK19. Difference in expression of HBME1 and CK19 was statistically significant for NIFTP vs FA (qualitative; p < 0.05) and NIFTP vs MNG (p < 0.05). No statistically significant difference was found for HBME1 in NIFTP vs PTC (conventional and FVPTC), p ≥ 0.2. Sensitivity of HBME1 and CK19 for NIFTP were 78% and 67%, ~ 88% each for PTC, and 89% and 100% for FVPTC, respectively, while specificity of HBME1 and CK19 for NIFTP were 53% each, ~ 62% each for PTC, and ~55% each for FVPTC.

CONCLUSION

Our study indicated that HBME1 and CK19 are valuable markers in differentiating NIFTPs from morphologic mimics like follicular adenoma and adenomatoid nodules/multinodular goiter. While HBME1 and CK19 are both sensitive in diagnosing lesions with PTC-like nuclear features, CK19 stains a higher number of benign lesions in comparison to HBME1. No increase in sensitivity or specificity in diagnosis of NIFTP, PTC, or FVPTC was noted on combining the two antibodies.

ESMO recommendations on the standard methods to detect RET fusions and mutations in daily practice and clinical research

Aberrant activation of RET is a critical driver of growth and proliferation in diverse solid tumours. Multikinase inhibitors (MKIs) showing anti-RET activities have been tested in RET-altered tumours with variable results. The low target specificity with consequent increase in side-effects and off-target toxicities resulting in dose reduction and drug discontinuation are some of the major issues with MKIs. To overcome these issues, new selective RET inhibitors such as pralsetinib (BLU-667) and selpercatinib (LOXO-292) have been developed in clinical trials, with selpercatinib recently approved by the Food and Drug Administration (FDA). The results of these trials showed marked and durable antitumour activity and manageable toxicity profiles in patients with RET-altered tumours. The European Society for Medical Oncology (ESMO) Translational Research and Precision Medicine Working Group (TR and PM WG) launched a collaborative project to review the available methods for the detection of RET gene alterations, their potential applications and strategies for the implementation of a rational approach for the detection of RET fusion genes and mutations in human malignancies. We present here recommendations for the routine clinical detection of targetable RET rearrangements and mutations.

Molecular testing in diagnosis of indeterminate thyroid cytology: Trends and drivers

Fine needle aspiration (FNA), the cornerstone of diagnosis in thyroid swellings, fails to render a definitive diagnosis in about 20% to 30% of cases that are reported as indeterminate on cytology. Since the clinical management in thyroid rests on the risk of malignancy (ROM) in a given nodule, this distinction between "benign" and "possibly malignant" assumes paramount clinical importance. Over the last two decades, tremendous progress has been achieved in our understanding of the molecular basis of thyroid pathologies leading to identification of several genetic alterations that could potentially be exploited for diagnostic, prognostic and therapeutic purposes. An array of molecular tests has hit the markets aiming to predict the ROM in thyroid nodules. A deeper understanding of the strengths and limitations of these tests is imperative to be able to judiciously choose the right molecular test in a given case for maximum clinical benefit. This narrative review provides an overview of current status of molecular testing in the evaluation of thyroid nodules encompassing the current status and applications of these tests in diagnostic, prognostic and therapeutic areas along with a brief insight into the future developments in this field.

Evaluation of Diagnostic Utility of Immunohistochemistry Markers of TROP-2 and HBME-1 in the Diagnosis of Thyroid Carcinoma

OBJECTIVE

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.

STUDY DESIGN

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.

RESULT

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.

CONCLUSION

IHC panel consisting of TROP-2 and HBME-1 can be used in equivocal follicular patterned lesions for the diagnosis of thyroid carcinomas.

Diagnostic Value of TROP-2 and CK19 Expression in Papillary Thyroid Carcinoma in Both Surgical and Cytological Specimens

Papillary thyroid carcinoma (PTC) represents the most common primary malignant thyroid tumor and its diagnosis is dependent on the presence of classic nuclear features that are sometimes seen in some non-neoplastic and benign lesions. Several immunohistochemical markers are used individually or in combination to help in differentiation of PTC from mimickers. The aim of the current study was to assess the diagnostic value of TROP-2 and cytokeratin 19 (CK19) expression in differentiating PTC from other mimickers both singly and in combination. The current study was carried out on 77 surgical specimens (56 PTC and 21 non-neoplastic cases) and 12 cytological specimens (4 THY2, 6 THY4, and 2 THY5). TROP-2 was negative in 81% of non-neoplastic surgical specimens and in 100% of THY2 cytological specimens while it was positive in 71.4% of PTC surgical specimens and 100% of THY4/THY5 cytological specimens. Sensitivity and specificity of TROP-2 positive expression for diagnosis of PTC in surgical specimens reached 71% and 81%, respectively, while it reached 100% for both in cytological specimens. Cytokeratin 19 showed positive expression in 85.7% of non-neoplastic surgical specimens and in 92.9% of PTC surgical specimens. Cytokeratin 19 showed negative expression in 75% of Thy2 cases while it was positive in all studied Thy4 and Thy5 cases. Sensitivity and specificity of CK19 total estimated score for diagnosis of PTC in surgical specimens were 78.6% and 66.7%, respectively, while it reached 100% and 75% in cytological specimens. Positive TROP-2 and CK19 expression in PTC were associated with lymph node metastasis. TROP-2 is a specific rather than sensitive marker while CK19 is a sensitive rather than specific marker in differentiating PTC from other mimickers in surgical specimens. The diagnostic validity of both markers was superior in diagnosis of classic PTC compared with follicular variant PTC. TROP-2 is superior to CK19 in diagnosis of PTC in cytological specimens. Both TROP-2 and CK19 could be used preoperatively in adjunct to hematoxylin and eosin for more confident diagnosis of thyroid cytology and along with radiology as predictors of lymph node metastasis.

Role of Immunohistochemistry in Fine Needle Aspiration and Core Needle Biopsy of Thyroid Nodules

Objectives

Immunohistochemistry (IHC) has been used for the diagnosis of indeterminate results in fine needle aspiration (FNA) of thyroid nodules. However, the role of IHC in core needle biopsy (CNB) is not clear and the efficacy of testing for molecular markers following CNB has not been evaluated. The aim of this study is to compare the role of IHC staining in CNB with that in FNA when examining thyroid nodules and to compare the sensitivity and usefulness of different molecular markers.

Methods

Consecutive cases of thyroid FNA and CNB accompanied by IHC from 2004 to 2014 were included in this study with retrospective review of medical record. The rate of remaining nondiagnostic result (unsatisfactory, atypia of undetermined significance or follicular lesion of undetermined significance [AUS/FLUS]) and rate of strong expression of each molecular marker according to the diagnosis were evaluated.

Results

IHC was more frequently performed in CNB with multiple molecular markers compared to FNA (38.1% vs. 2.8%, 3 or 4 markers [Gal-3, HBME-1, CK19, and CD56] vs. 1 marker [Gal-3]). In the CNB group, 11.3% remained as AUS/FLUS after IHC, and the rate remaining nondiagnostic was significantly less than in the FNA group (42.9%). Gal-3 and CK19 showed higher specificity and expressed mainly in conventional type of papillary carcinoma and HBME-1 showed higher sensitivity for the diagnosis of carcinoma with expression in both conventional type and follicular variant papillary thyroid carcinoma.

Conclusion

With these data, we could conclude that IHC was more effective following CNB than following FNA.

Approach the Invasive Potential with Hurthle Cell Tumors of Thyroid

To observe the expression of P53, CyclinD1, Ki-67, Galectin-3, COX-2, Bcl-2 and approach their contribution on assessing the invasive potential for Hurthle cell tumors. Seventy-three cases of Hurthle cell tumor were collected for immunohistochemistry staining. The patients were followed up with 8 months to 5 years. Tumors were divided into four grades according to invasion and diameter:(1) extremely low risk (27 cases that less than 2 cm and without invasion), (2) low risk (18 cases that within 2-3.9 cm and without invasion), (3) moderate risk (21 cases that achieve 4 cm and without invasion), (4) high risk (7 cases that with invasion of capsule/vessel in spite of the diameter). Immunostaining presented that all 73 cases were positive with Galectin-3, COX-2 and Bcl-2. For each group, P53 positive were 29.6%, 55.6%, 90.5%, 100.0%; CyclinD1 stained with 7.4%,22.2%,52.4%,100.0% and Ki-67 were 0.0%,5.6%,9.5%,28.6%, respectively. The higher risk of tumor, the more cases that positive expressed P53 and CyclinD1. After following up within 49 patients, two of the recurring cases were positive with P53 and CyclinD1 and one of which was also highly expressed Ki-67. Detecting P53, CyclinD1 and Ki-67 might provide reference for invasive potential assessment with Hurthle cell tumors but not Galectin-3, COX-2 and Bcl-2.

Galectin-3 Performance in Histologic a Cytologic Assessment of Thyroid Nodules: A Systematic Review and Meta-Analysis

The literature on Galectin-3 (Gal-3) was systematically reviewed to achieve more robust information on its histologic reliability in identifying thyroid cancers and on the concordance between Gal-3 test in histologic and cytologic samples. A computer search of the PubMed and Scopus databases was conducted by combinations of the terms thyroid and Gal-3. Initially, 545 articles were found and, after their critical review, 52 original papers were finally included. They reported 8172 nodules with histologic evaluation of Gal-3, of which 358 with also preoperative FNAC Gal-3 assessment. At histology, Gal-3 sensitivity was 87% (95% confidence intervals [CI] from 86% to 88%), and specificity 87% (95% CI from 86% to 88%); in both cases, we found heterogeneity (I₂ 85% and 93%, respectively) and significant publication bias (p < 0.001). The pooled rate of positive Gal-3 at fine needle aspiration (FNAC) among cancers with histologically proven Gal-3 positivity was 94% (95% CI from 89% to 97%), with neither heterogeneity (I₂ 14.5%) nor bias (p = 0.086). These data show high reliability of Gal-3 for thyroid cancer at histology, while its sensitivity on FNAC samples is lower. The limits of cytologic preparations and interpretation of Gal-3 results have to be solved.

Hepatocyte Growth Factor/C-Met Axis in Thyroid Cancer: From Diagnostic Biomarker to Therapeutic Target

The hepatocyte growth factor (HGF)/c-met axis plays a crucial role in cancer development by promoting cellular proliferation, motility, and morphogenesis, as well as angiogenesis. Different cellular distributions of both the ligand and the receptor in benign vs malignant lesions indicate this biological system as a candidate for a diagnostic biomarker of malignancy occurring in endocrine glands, such as the thyroid and pituitary. Furthermore, the HGF/c-met expression may help to identify a subset of patients eligible for potential targeted therapies with HGF/c-met inhibitors or antagonists in thyroid tumour, as well as in other malignancies. This may be relevant for iodine-refractory cancers, the treatment of which is still a major challenge. With this in mind, HGF/c-met expression in thyroid cancer tissue may be useful for prognostic and therapeutic stratification of patients.

APLP2, RRM2, and PRC1: New Putative Markers for the Differential Diagnosis of Thyroid Follicular Lesions

BACKGROUND

Current methods based on fine-needle aspiration biopsy (FNAB) are not sufficient to distinguish among follicular thyroid lesions, follicular adenoma (FA), follicular thyroid carcinoma (FTC), and the follicular variant of papillary thyroid cancer (FVPTC). Furthermore, none of the immunohistochemical markers currently available are sensitive or specific enough to be used in the clinical setting, necessitating a diagnostic hemithyroidectomy. The aim of this study was to identify proteins of value for differential diagnosis between benign and malignant thyroid follicular lesions.

METHODS

This retrospective analysis is based on an assessment of the immunoexpression of 19 proteins on 81 benign thyroid lesions (FA) and 50 malignant tumors (FTC/FVPTC). The resulting expression profile allowed the design of a scoring system model to improve the differential diagnosis of benign and malignant thyroid lesions. The model was validated using an independent series of 69 FA and 40 FTC and an external series of 40 nodular hyperplasias, and was further tested in a series of 38 FNAB cell blocks.

RESULTS

A model based on the nuclear and cytoplasmic expression of APLP2, RRM2, and PRC1 discriminated between benign and malignant lesions with 100% sensitivity in both main and validation groups, with specificities of 71.3% and 50.7%, respectively. For the nodular hyperplasia series, specificity reached 94.8%. Finally, in FNAB samples, the sensitivity was 100% and the specificity was 45% for discrimination between benign and malignant lesions.

CONCLUSIONS

These findings suggest that the identified APLP2, RRM2, and PRC1 signature could be useful for distinguishing between benign (FA) and malignant (FTC and FVPTC) tumors of the thyroid follicular epithelium.

Study of Immunohistochemical Markers (CK-19, CD-56, Ki-67, p53) in Differentiating Benign and Malignant Solitary Thyroid Nodules with special Reference to Papillary Thyroid Carcinomas

INTRODUCTION

Solitary Thyroid Nodule (STN) has provoked increased concern owing to higher incidence of malignancy. The inter and intra observer variation in the histomorphological diagnosis of Papillary Thyroid Carcinomas (PTC) may sometimes pose a diagnostic difficulty.

AIM

This study was undertaken to analyse immunohistochemical (IHC) markers (CK-19, CD-56, p53, Ki-67) to differentiate between benign and malignant surgically resected STN along with their utility in the identification of PTC.

MATERIALS AND METHODS

The present cross sectional study was conducted over a period of 4 years. A technique of manual tissue array was employed for cases subjected to IHC. The primary antibodies used were CK-19, CD-56, p53 and Ki-67. Analysis of the expression of IHC markers (p53, Ki-67) to distinguish between benign and malignant STN was done. Evaluation and correlation of expression of IHC markers (CK-19, CD-56) to determine its utility in reaching definitive diagnosis and assessing prognosis of PTC was tried. Results were subjected to statistical analysis. The results were considered to be significant when the p-value <0.05.

RESULTS

Out of the 160 cases of surgically resected STN specimens, 68 cases were non-neoplastic, 24 cases were benign and 68 cases were of malignant tumours (7 cases of follicular carcinoma (FCa), 61 cases of PTC). CK-19 was found to be a sensitive (83.61%) and a highly specific positive marker (100%) for the diagnosis of PTC. The difference in CD-56 expression between PTC and non-PTC group was found to be highly statistically significant. CD-56 was found to be a sensitive (85.86%) and specific (82.25%) negative marker in differentiating PTC from follicular lesions/neoplasms. The difference in p53 expression between the malignant and non-malignant STN cases was found to be highly statistically significant with a sensitivity and specificity 85.29% and 70.65% respectively. The statistical difference in mean Ki-67 Labeling Index (LI) was found to be significant between PTC versus FA, PTC versus non-neoplastic lesions, FA versus FCa and FVPTC versus FA.

CONCLUSION

The panel of four IHC markers (CK-19, CD-56, p53, Ki-67) may be used for differentiating doubtful benign STN cases from malignant ones and also for definitive diagnosis of PTC along with histopathological examination.

Metabolomic analysis of percutaneous fine-needle aspiration specimens of thyroid nodules: Potential application for the preoperative diagnosis of thyroid cancer

Thyroid nodules are a very common problem. Since malignant thyroid nodules should be treated surgically, preoperative diagnosis of thyroid cancer is very crucial. Cytopathologic analysis of percutaneous fine-needle aspiration (FNA) specimens is the current gold standard for diagnosing thyroid nodules. However, this method has led to high rates of inconclusive results. Metabolomics has emerged as a useful tool in medical fields and shown great potential in diagnosing various cancers. Here, we evaluated the potential of nuclear magnetic resonance (NMR) analysis of percutaneous FNA specimens for preoperative diagnosis of thyroid cancer. We analyzed metabolome of FNA samples of papillary thyroid carcinoma (n = 35) and benign follicular nodule (n = 69) using a proton NMR spectrometer. The metabolomic profiles showed a considerable discrimination between benign and malignant nodules. Receiver operating characteristic (ROC) curve analysis indicated that seven metabolites could serve as discriminators (area under ROC curve value, 0.64–0.85). These findings demonstrated that NMR analysis of percutaneous FNA specimens of thyroid nodules can be potentially useful in the accurate and rapid preoperative diagnosis of thyroid cancer.

CD56, HBME-1 and cytokeratin 19 expressions in papillary thyroid carcinoma and nodular thyroid lesions

Background:

Carcinomas of the thyroid follicular epithelium are the most common cancers of the endocrine system. In the diagnosis of thyroid nodules and tumors, the gold standard is histological evaluation. In cases which have morphological overlap, immunohistochemistry is needed for differential diagnosis. The purpose of this study is to investigate the expressions of CD56, HBME-1, cytokeratin 19 (CK19) antibodies in papillary thyroid carcinoma (PTC) and thyroid nodular lesions and their contributions to differential diagnosis.

Materials and Methods:

In this study, 47 PTCs (26 follicular variant, 21 classic type) and 26 benign thyroid lesions (15 nodular hyperplasia, 10 follicular adenomas, 1 Hurtle cell adenoma) were analyzed retrospectively. HBME-1, CK19, and CD56 antibodies were performed with immunohistochemical methods. The results were evaluated statistically.

Results:

+3 staining with HBME-1 and CK19 was observed in 72.3% and 83% of patients with PTC. In 95.7% of PTC cases, loss of CD56 expressions in various degrees was identified. A statistically significant difference was detected in HBME-1, CK19, and CD56 expressions between PTCs and benign lesions (P < 0.001).

Conclusion:

In our study, positive staining of HBME-1, CK19, and loosing expression of CD56 that supports malignancy was found and concluded that CD56 is a helpful antibody for the differential diagnosis of benign and malignant lesions and may increase the diagnostic accuracy when used with HBME-1 and CK19.

Expression of Cytokeratin-19 and Thyroperoxidase in Relation to Morphological Features in Non-Neoplastic and Neoplastic Lesions of Thyroid

INTRODUCTION

Thyroperoxidase (TPO) is a protein involved in thyroid hormone synthesis. TPO gene suppression and mutation were involved in thyroid tumours. CK-19 plays important role in the structural integrity of epithelial cells. Reduced TPO expression with increased CK-19 immunoreactivity has been implicated as a marker for differentiating non neoplastic and neoplastic thyroid lesions.

AIM

To study the histopathological features of thyroid lesions and to evaluate the diagnostic role of thyroperoxidase and CK-19 in non-neoplastic and neoplastic thyroid lesions.

MATERIALS AND METHODS

Prospective observational study of 65 thyroid specimens was studied for detailed histopathological examination and Expression of Immunohistochemical Markers Cytokeratin-19 (CK-19) and Thyroperoxidase.

RESULTS

TPO IHC marker was expressed by non-neoplastic and benign lesions of thyroid but not in malignancy. CK-19 was expressed 100% in papillary carcinoma of thyroid and its variants, focal and weak staining noted in goitre and hyperplastic areas.

CONCLUSION

Most of the non-neoplastic and neoplastic lesions were diagnosed based on histopathological features. When the histopathological diagnosis are equivocal, immunohistochemical markers aids in diagnosing malignancy. Diffuse and strong TPO expression indicates non-neoplastic thyroid lesions whereas diffused and strong CK-19 expression indicates thyroid malignancy.

Diagnostic significance of elevated expression of HBME-1 in papillary thyroid carcinoma

This study examined the association between hector battifora mesothelial antigen-1 (HBME-1) expression and papillary thyroid carcinoma (PTC). A total of 206 patients were enrolled in the current study including 96 PTC patients and 110 patients with benign thyroid nodules (BTN). Immunohistochemistry (Envision) were performed to assess the expression of HBME-1. Receiver operating characteristic curve (ROC) curves were applied to evaluate the diagnostic tumor node metastasis (TNM) value of HBME-1. Specimens from 96 patients with PTC and 110 patients with BTC were reviewed. HBME-1 was positively immunostained in PTC tissue, which was significantly higher than that in BTN tissues (77.1 vs. 5.77 %, P < 0.05). Immunohistochemistry also identified that HBME-1 expression did not show any statistically significant differences based on gender, age, tumor size, TNM stage, and lymph node metastasis (P > 0.05). Importantly, HBME-1 expression was correlated with infiltration levels and differential levels in PTC (both P < 0.05). HBME-1 was found to have high sensitivity (94.5 %) and specificity (77.08 %) for PTC diagnosis. Moreover, HBME-1 had a high specificity (83.33 %) at identifying the differential levels of PTC, but a low sensitivity (22.92 %). The sensitivity and specificity of HBME-1 identifying the infiltration levels of PTC were, respectively, 72.70 and 72.00 %. HBME-1 was highly expressed in PTC tissues, and HBME-1 can serve as a potential biomarker in the diagnosis of PTC.

Cytokeratin 19 expression patterns of dentigerous cysts and odontogenic keratocysts

Background:

Although numerous investigators have studied the pattern of keratin expression in different odontogenic cysts, the results have been variable.

Aim:

The present study was conducted to determine the pattern of expression of cytokeratin 19 (CK 19) in the epithelial lining of odontogenic keratocysts and dentigerous cysts.

Materials and Methods:

The epithelial layers showing expression of the epithelial marker CK 19 was determined by immunohistochemical methods in 15 tissue specimens each of histopathologically confirmed cases of dentigerous cysts and odontogenic keratocysts. Statistical analysis was done to compare the CK 19 expression between dentigerous cyst and odontogenic keratocyst using the Chi-square test. P < 0.05 was considered to be statistically significant.

Results:

All specimens of dentigerous cysts were positive for CK 19 with 20% (3/15) of the specimens showing expression only in a single layer of the epithelium, 40% (6/15) of the specimens showing expression in more than one layer but not the entire thickness of the epithelium, and the remaining 40% (6/15) showing expression throughout the entire thickness of the epithelium. In the case of odontogenic keratocysts, 40% (6/15) of the specimens were negative for CK 19, 40% (6/15) of the specimens showed expression only in a single layer of the epithelium, and 20% (3/15) of the specimens showed expression in more than one layer, but not the entire thickness of the epithelium. The observed differences in CK 19 expression by the two lesions were statistically significant (P < 0.01).

Conclusion:

The differences in CK 19 expression by these cysts may be utilized as a diagnostic tool in differentiating between these two lesions.

Serum Galectin-3: diagnostic value for papillary thyroid carcinoma

OBJECTIVE

Thyroid cancer constitutes approximately 1% of all cancers, approximately 90% of the endocrine malignancies, and is responsible for 0.4% of cancer-related deaths. Additional markers are required for the accurate diagnosis of thyroid malignancies. There is no marker that can accurately facilitate pre-operative benign-malignant differentiation of thyroid nodules. The present study aims to evaluate the diagnostic value of preoperative serum Galectin-3 levels in thyroid cancer and to avoid unnecessary aggressive interventions.

MATERIAL AND METHODS

Sixty-four patients who were operated between May 2009 and April 2011 were included in this study prospectively. Patients with toxic nodules and those with malignancies detected in preoperative fine needle aspiration biopsies (FNAB) were excluded. Patients with thyroid nodules of >3 cm in ultrasonography or having suspicious cytological findings in their preoperative FNABs regardless of the nodule size were included. Patients were divided into 2 groups, "control"and "cancer," according to the postoperative pathology results.

RESULTS

The control group included 50 and cancer group included 14 patients. The mean age of the control group was 44.84±13.17 (19-79), while it was 44.14±15.94 (25-72) in the cancer group. A statistically significant difference was found between Galectin-3 levels in the cancer and control groups (p<0.001).

CONCLUSION

In the present study, serum Galectin-3 levels in patients with malignant nodules were statistically significant.

The Diagnostic Usefulness of HMGA2, Survivin, CEACAM6, and SFN/14-3-3 δ in Follicular Thyroid Carcinoma

Background:

Follicular thyroid carcinoma (FTC) is the second most common thyroid malignancy and its differential diagnosis includes follicular adenoma (FA) and adenomatous goiter (AG). Several ancillary markers have been suggested to aid in the diagnosis of FTC, but the successful use of these methods still needs to be validated.

Methods:

In the present study, we verified the immunoexpression of HMGA2, CEACAM6, survivin, and SFN/14-3-3 δ in lesions including 41 AGs, 72 FAs, and 79 FTCs. We evaluated their diagnostic usefulness, combined with galectin 3, Hector Battifora mesothelial 1 (HBME1), cytokeratin 19, and cyclin D1, in diagnosing FTC.

Results:

The expressions of HBME1 (65.8%) and HMGA2 (55.7%) were significantly higher in FTCs than in FAs and AGs (p<.001 and p=.005, respectively). HBME1 was the only marker that was more frequently expressed in FTCs than in FAs (p=.021) and it was more frequently expressed in follicular neoplasms than in AGs (p<.001). Among the novel markers, the combination of HMGA2 and HBME1 showed the highest sensitivity (72.2%) and specificity (76.1%) for diagnosing FTC. CEACAM6, survivin, and SFN/14-3-3 δ were barely expressed in most cases.

Conclusions:

Our present results show that only HMGA2 can be beneficial in differentiating FTC using the novel markers.

Application of Immunohistochemistry in Thyroid Pathology

Context

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.

Objective

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.

Data Sources

Literature review, authors' research data, and personal practice experience.

Conclusions

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.

Ovarian metastasis from thyroid carcinoma: a case report and literature review

BACKGROUND

Papillary thyroid carcinoma is rarely associated with metastatic disease. The most common sites of metastasis are the lungs and bones, while only few cases of ovarian metastasis are described in literature.

CASE

We report the case of a 51 years old woman, treated 9 years before for papillary thyroid carcinoma, presenting to our Institute with a pelvic ovarian mass revealed by ultrasound imaging. After bilateral salpingo-oophorectomy, the histologic examination detected a left ovarian metastasis from papillary thyroid carcinoma.

CONCLUSION

Even if the diagnosis of ovarian metastasis from thyroid carcinoma is often controversial, it should be considered when a woman with an ovarian lesion of unknown origin, has a personal history of malignant thyroid disease.

VIRTUAL SLIDES

The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/13000_2014_193.

Immunohistochemical expression of HBME-1 and galectin-3 in the differential diagnosis of follicular-derived thyroid nodules

BACKGROUND

Thyroid nodules are common among adults with only a small percentage being malignant and histologically mimic benign nodules. Accurate diagnosis of these thyroid nodules is critical for the proper clinical management. The determination of malignancy in follicular patterned thyroid lesions is based on postoperative histological findings. Therefore, affected patients are referred for surgery, although only 10% will have a final diagnosis of malignancy. The aim of this study was to investigate the ability of two immunohistochemical (IHC) markers; galectin-3 and Hector Battifora mesothelial-1 (HBME-1) individually or in combination, to distinguish between benign (non-neoplastic and neoplastic) and malignant (follicular and papillary carcinomas) thyroid lesions removed by surgical resection.

METHODS

We investigated the immunoexpression of galectin-3 and HBME-1 in 50 cases of benign and malignant thyroid nodules. The benign group included 13 cases of thyroid nodular goiter (NG) and 9 cases of follicular adenoma (FA). The malignant group included 5 cases of follicular thyroid carcinomas (FC), 18 cases of classic papillary thyroid carcinoma and 5 cases of follicular variant papillary carcinoma (FVPC).

RESULTS

The staining results showed that malignant tumors expressed galectin-3 and HBME-1 significantly more than benign nodules. The sensitivity of these markers for the distinction between benign and malignant lesions ranged from 89.3% to 92.9%. Co-expression of galectin-3 and HBME-1 was seen in 82.1% of carcinomas, but in none of the benign nodules. Immunoexpression was usually diffuse in malignant tumors, and focal in the benign lesions.

CONCLUSION

Our findings indicate that these immunohistochemical markers are significantly more expressed in malignant tumors compared to benign lesions and may be of additional diagnostic value when combined with routine histology. Galectin-3 has higher sensitivity and specificity of immunoexpression in thyroid malignancy than HBME-1, and the combined use of galectin-3 and HBME-1 can increase the specificity of immunoexpression in malignant tumors.

Molecular diagnostics for thyroid nodules: the current state of affairs

Molecular diagnostics offers great promise for the evaluation of cytologically indeterminate thyroid nodules. Numerous molecular genetic and immunohistochemical tests have been developed that may be performed on thyroid specimens obtained during standard fine-needle aspiration, some of which may greatly improve diagnostic yield. A sound understanding of the diagnostic performance of these tests, and how they can enhance clinical practice, is important. This article reviews the diagnostic utility of immunohistochemical and molecular testing for the clinical assessment of thyroid nodules, and makes recommendations about how these tests can be integrated into clinical practice for patients with cytologically indeterminate thyroid nodules.

Utility of immunohistochemical markers in diagnosis of follicular cell derived thyroid lesions

Differentiating the follicular derived lesions can be challenging. Although immunohistochemistry is generally accepted as a useful ancillary technique in the diagnosis, controversy exists regarding the best marker or combination of markers to distinguish each lesion from its mimics. In this study, we aimed at evaluating multiple markers to compare their sensitivity and usefulness, and to find out if a combination of the evaluated markers can be of additional value in discriminating thyroid lesions. The study included two groups of follicular derived thyroid lesions; benign group (Grave's disease, nodular goiter, Hashimoto's and adenoma) and malignant group (papillary, follicular carcinoma, well differentiated tumors of unknown malignant potential and follicular tumour of unknown malignant potential). Immunohistochemical evaluation of CD56, HBME-1, Gaectin-3 and CK19 were done. The sensitivity, specificity for each marker and their combination were calculated. Each marker was sensitive and specific for certain lesion but the sensitivity and specificity was increased when use combination of markers. Although no single marker is completely sensitive and specific for follicular thyroid lesions, the combination of CD56, HBME-1, Gaectin-3 and CK19 attains high sensitivity and specificity in diagnosis.

Analysis of BRAF(V600E) mutation and DNA methylation improves the diagnostics of thyroid fine needle aspiration biopsies

BACKGROUND

Thyroid nodules with indeterminate cytological features on fine needle aspiration biopsy specimens (FNABs) have a ~20% risk of thyroid cancer. BRAF(V600E) mutation and DNA methylation are useful markers to distinguish malignant thyroid neoplasm from benign. The aim of this study was to determine whether combined detection of BRAF(V600E) mutation and methylation markers on FNABs could improve the diagnostic accuracy of thyroid cancer.

METHODS

Using pyrosequencing and quantitative methylation-specific PCR (Q-MSP) methods, FNABs from 79 and 38 patients with thyroid nodules in training and test groups, respectively, were analyzed for BRAF(V600E) mutation and gene methylation.

RESULTS

BRAF(V600E) mutation was found in 30/42 (71.4%) and 14/20 (70%) FNABs in training and test groups, respectively. All BRAF(V600E)-positive samples were histologically diagnosed as papillary thyroid cancer (PTC) after thyroidectomy. As expected, BRAF mutation was not found in all benign nodules. Moreover, we demonstrated that the five genes, including CALCA, DAPK1, TIMP3, RAR-beta and RASSF1A, were aberrantly methylated in FNABs. Of them, methylation level of DAPK1 in PTCs was significantly higher than that in benign samples (P <0.0001). Conversely, methylation level of RASSF1A in PTCs was significantly lower than that in benign samples (P =0.003). Notably, compared with BRAF mutation testing alone, combined detection of BRAF mutation and methylation markers increased the diagnostic sensitivity and accuracy of PTC with excellent specificity.

CONCLUSION

Our data have demonstrated that combine analysis of BRAF mutation and DNA methylation markers on FNABs may be a useful strategy to facilitate the diagnosis of malignant thyroid neoplasm, particularly PTC.

VIRTUAL SLIDES

The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/6080878071149177.

Establishment of monoclonal anti-human CD26 antibodies suitable for immunostaining of formalin-fixed tissue

Background

A T cell costimulatory molecule with dipeptidyl peptidase IV (DPPIV) activity in its extracellular region, CD26 is a multifunctional molecule associated with various proteins such as adenosine deaminase, caveolin-1, CXCR4, collagen, and fibronectin, while playing an important role in the regulation of inflammatory responses and tumor biology. We have focused on CD26 as a novel therapeutic target for various tumors and immune disorders, and have developed a humanized anti-CD26 monoclonal antibody (mAb), YS110, which is currently being evaluated in a phase I clinical trial for patients with CD26-expressing tumors, including malignant mesothelioma. Since detection of tumor CD26 expression is required for determining potential eligibility for YS110 therapy, the development of anti-human CD26 mAb that can clearly and reliably detect the denatured CD26 molecule in the formalin-fixed paraffin-embedded tissues is critical.

Methods

To develop novel anti-CD26 mAbs capable of binding to the denatured CD26, we immunized mice with CD26 protein denatured in urea buffer. After the fusion of splenocytes and myeloma cells, the mAbs were screened for specific reactivity with human CD26 by flow cytometry, enzyme-linked immunosorbent assay, and immunohistochemistry. The binding competitiveness of novel anti-CD26 mAbs with the humanized anti-CD26 mAb YS110 was also examined.

Results

We have succeeded in developing novel anti-human CD26 mAbs suitable for immunohistochemical staining of CD26 in formalin-fixed tissue sections with reliable clarity and intensity. Importantly, some of these mAbs exhibit no cross-reactivity with the humanized anti-CD26 mAb.

Conclusions

These novel mAbs are potentially useful as companion diagnostic agents to analyze CD26 expression in the clinical setting while advancing future CD26-related research.

Virtual slides

The virtual slides for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/5987140221097729

Contribution of immunocytochemical stainings for galectin-3, CD44, and HBME1 to fine-needle aspiration cytology diagnosis of papillary thyroid carcinoma

In cytology practice some papillary thyroid carcinoma (PTC) cases have indeterminate diagnoses and overlapping cytological features with benign lesions. This study was undertaken to find out if immunocytochemistry using Galectin-3, CD-44 and HBME-1 could be of help in such situations. Forty-six cases consisting of 22 malignancy (PTC) cases, 7 suspicious of (S/O) PTC, 1 follicular neoplasm, 5 follicular lesion of undetermined significance (FLUS), and 11 benign (colloid goiter) cases diagnosed by FNA were included in this study. Staining reactions were graded in a sliding scale of -, 1+, 2+, 3+, and 4+. In an assessment of 100 cells, each cell with weak, and moderate to strong positive reaction were assigned a score of 1 and 4, respectively. Staining reaction of ≥+2 and scores >100 were considered positive. Frequency of cases with ≥+2 reaction, and scores >100 for each of Galectin-3, CD-44, and HBME-1 were significantly higher in PTC or combined PTC and S/O PTC cases as compared with FLUS and benign cases taken together (P = 0.01744 to 0.00000). When the cases were compared according to histological malignant and benign diagnoses, the difference was also significant in respect of ≥+2 reaction, and scores >100 for Galectin-3 and CD44 (P = 0.04923 to 0.00947); however, there was no significant difference, when these parameters for HBME1 were compared. Galectin 3, CD 44, and to some extent HBME 1 are useful immunocytochemical parameters with potential to support FNAC diagnosis of PTC, especially in situations with difficult differential diagnoses.

Combined staining for immunohistochemical markers in the diagnosis of papillary thyroid carcinoma: Improvement in the sensitivity or specificity?

Objectives

To investigate the ability of cytokeratin (CK)-19, galectin-3, human bone marrow endothelial cell (HBME)-1 and tyrosine kinase-type cell surface receptor HER2 (HER-2/neu) to differentiate papillary thyroid carcinoma (PTC) from benign thyroid nodules.

Methods

Archival specimens of PTC and benign thyroid nodules were included in this retrospective immunohistochemical study. CK-19, galectin-3, HBME-1, and HER-2/neu protein levels were analysed immunohistochemically using routinely prepared tissue sections.

Results

Specimens from 331 patients with PTC and 664 patients with benign thyroid nodules were reviewed. For all four protein markers, the percentage of samples with cells that demonstrated positive immunostaining was significantly higher in PTC specimens than in benign thyroid nodules. As a single protein marker, CK-19 was the most sensitive (92.7%) and HBME-1 was the most specific (97.9%). The combination of CK-19 and galectin-3 was the most sensitive (82.8%), and the combinations of HBME-1 with CK-19 or galectin-3 or HER-2/neu were the most specific (98.3%).

Conclusions

The combination of HBME-1 and either CK19 or galectin-3 or HER-2/neu can improve the specificity of the diagnosis of PTC.

Immunohistochemical markers in the diagnosis of papillary thyroid carcinomas: The promising role of combined immunostaining using HBME-1 and CD56

We aimed to evaluate the expression and diagnostic value of five immunohistochemical markers (HBME-1, Galectin-3, CK19, CD56 and p63) in a very large series of unequivocal papillary thyroid carcinoma (PTC) cases, including both the classic (CPTC) and the follicular variant (FVPTC). We performed an immunohistochemical analysis on a tissue micro-array of 204 PTCs (98 CPTCs, 90 FVPTCs, and 16 other variants). HBME-1 was the most sensitive marker, staining 95.9% of CPTCs and 81.1% of FVPTCs. CD56, a marker whose expression is reduced or absent in thyroid carcinoma, revealed a negative, "malignant" profile in 93.9% of CPTCs and 73.3% of FVPTCs. Galectin-3, CK19 and p63 were positive in 64.7%, 45.6% and 6.9% of PTCs, respectively. The immunopanel consisting of HBME-1, CD56 and/or CK19 reached the highest sensitivity (95.6%). The co-expression of 2 or more proteins was observed in 88.2% of PTCs, with HBME-1 and CD56 being the most frequent positive association (79.4%). We report a new panel of antibodies consisting of HBME-1, CK19 and CD56 that was found to be highly sensitive for both CPTC and FVPTC. This panel could be recommended as a supplement to the morphological criteria in the diagnosis of difficult FVPTC cases.

Correlation of immunohistochemical markers and BRAF mutation status with histological variants of papillary thyroid carcinoma in the Korean population

Several pathologic characteristics are associated with an adverse clinical outcome in papillary thyroid carcinoma (PTC), including the histological variant. This study aimed to investigate immunohistochemical expression and BRAF mutation status based on the histological variant and evaluated potential markers of aggressive behavior of PTC in Korean patients. In all, 407 PTC cases were classified to each histological variant, and the 94 representative cases were subjected to immunohistochemistry and BRAF mutation analysis. The classic type, follicular variant (FV) and tall cell variant (TCV) represented 76.9%, 14.2% and 6%, respectively. TCV showed a larger tumor size (P = 0.009), frequent extrathyroidal extension (P = 0.022) and cervical lymph node (LN) metastasis (P = 0.018). TCV and FV showed the reduced expression of galectin-3 (P = 0.003) and HBME1 (P = 0.114). Regardless of histology, PTEN loss and diffuse S100A4 expression were associated with LN metastasis (P = 0.007, P = 0.013). All TCVs harbored BRAF V600E mutation, and FV harbored less BRAF V600E mutation (P = 0.043). Immunohistochemical evaluation showed characteristic patterns in histological variants. PTEN and S100A4 expression are suggested as indicators of regional lymph node metastasis.

A rare primary tumor of the thyroid gland: report a new case of leiomyosarcoma and literature review

Primary leiomyosarcomas of the thyroid gland are extremely rare. we report a case of a 72 year-old women with a painful growing mass of the left neck with skin fistula. The patient underwent a lobectomy. The tumor histology showed spindle-shaped cells arranged in interlacing fascicles that expressed desmine and Hcaldesmone, but were negative for cytokeratins and thyroglobulin. Total body CT scan didnt show any other tumor. The patient died two months after surgery. Primary thyroid leiomyosarcoma may be mistaken for other tumors, such as anaplastic or medullary carcinomas. Therefore, the diagnosis is difficult and requires numerous clinical, radiological, and pathological investigations.

Diagnostic utility of immunohistochemical panel in various thyroid pathologies

BACKGROUND

For management of thyroid nodules, distinction between benign and malignant tumours is essential. The study was performed to evaluate the diagnostic value of molecular markers in different thyroid tumours.

MATERIALS AND METHODS

Immunohistochemistry for CD56, HBME-1, COX-2, Ki-67, p53 and E-cadherin (E-CAD) was performed in 113 benign and 35 malignant thyroid lesions including 36 follicular adenomas (FA), 77 colloid goitres, 26 papillary thyroid carcinomas (PTC) and 9 follicular carcinomas (FC). The results were scored semiquantitatively by staining intensity (0-3 scale) and percentage of positive cells.

RESULTS

PTC was characterised by decreased E-CAD and CD56 expression in contrast to surrounding benign thyroid tissues. HBME-1 expression was absent in benign thyroid tissues but was notably high in PTC and occasionally in FC. The expression of E-CAD and CD56 in FA was significantly higher than in the surrounding thyroid tissues. No expression of p53 was found in any group. The expression of COX-2 was low in all lesions. The proliferation activity by Ki-67 was generally low; however, it was significantly higher in cancers.

CONCLUSIONS

The panel consisting of three markers, HBME-1, E-CAD and CD56, can be recommended as an adjunct to morphology criteria. HBME-1 is found in malignant lesions only and is the most sensitive and specific single marker in PTC. Decreased expression of E-CAD and CD56 distinguishes PTC from FA and FC. Both FA and FC are characterised by high expression of E-CAD and CD56. The practical use of Ki-67 is difficult due to low values. The role of adhesion factors in thyroid malignancies may be superior in comparison with cell proliferation.