Panel Of Immunohistochemical Markers Research Articles

Histo- and molecular pathology in gastroenteropancreatic neuroendocrine neoplasms

Neuroendocrine neoplasms are classified according to the WHO classification based on morphological criteria into neuroendocrine tumors, neuroendocrine carcinomas, and mixed neuroendocrine-non-neuroendocrine neoplasms. Neuroendocrine tumors are well differentiated neoplasms and show characteristic site-specific histological and molecular features, which is important for their clinical management. In cases dealing with metastasis, pathology often can help to identify the primary tumors using a small immunohistochemical marker panel. Neuroendocrine carcinomas are poorly differentiated neoplasms. They are subdivided into neuroendocrine carcinomas of small cell and large cell type. The molecular profile of neuroendocrine carcinomas and mixed neuroendocrine-non-neuroendocrine neoplasms shows a close relationship to conventional adenocarcinomas with site-specific features. Molecular analysis of neuroendocrine carcinomas and neuroendocrine-non-neuroendocrine neoplasms are not yet fully integrated in daily diagnostics and are mainly performed in the context of precision oncology.

Clinicopathological and Immunohistochemical Analysis of Lung Cancer Biopsies at a Tertiary Care Centre in Central Gujarat, India

Introduction: Lung biopsy is a reliable and highly accurate tool for diagnosing and subtyping lung lesions. Two-thirds of lung cancer patients present with advanced disease, and small biopsies remain the main diagnostic tool. Histopathological and immunohistochemical examination of lung biopsies plays an important role in accurately diagnosing lung malignancies. Aim: The aim of present study was to analyse the clinicopathological and immunohistochemical features of lung cancer. Materials and Methods: This cross-sectional study was conducted in the Department of Pathology, Medical College, Baroda, over a period of two years and three months, from March 2019 to May 2021. A total of 53 cases of malignant lung cancer biopsies were included in this study. Clinical parameters, such as patient age, complaints, smoking history, clinical presentation, radiological findings, histopathology reports, and IHC findings, were retrieved. All cases underwent histopathological examination, and tumour typing was done according to the WHO classification 2021 of lung tumours. Immunohistochemistry (IHC) markers like CK5/6, CK7, TTF1, P63, synaptophysin, chromogranin, and pankeratin were used for further subtyping. Data analysis was done by Microsoft Excel 2019 spreadsheet. Results: A total of 53 cases of malignant lung cancer were included in this study. Of these, 38 (71.69%) cases were male, and 15 (28.30%) cases were female. 43 (81.13%) cases were over 50 years old, with a mean age of 61 years. After IHC, adenocarcinoma was seen in 27 cases (50.9%), followed by Squamous Cell Carcinoma (SCC) in 19 cases (35.8%), five cases of small cell carcinoma, one case of large cell neuroendocrine carcinoma, and one case of Non Small Cell Carcinoma-Not Otherwise Specified (NSCC-NOS). In adenocarcinoma, positivity for CK7, TTF1, and p63 was 100%, 74.07%, and 16.6%, respectively. In squamous cell carcinoma, positivity for CK5/6 and p63 was 100% and 78.94%, respectively. Conclusion: In the present study, the majority of cases were males. Adenocarcinoma was the most common subtype of Non Small Cell Lung Cancer (NSCLC). A panel of IHC markers is helpful in differentiating NSCLC into adenocarcinoma and squamous cell carcinoma on small true-cut lung biopsies. CK5/6 and p63 aid in detecting squamous cell carcinoma, while CK7 and TTF-1 help in detecting adenocarcinoma. The recommended immunohistochemical profile for NSCLC includes TTF1, CK5/6, CK7, and p63.

Prognostic value of a panel of immunohistochemical markers for determining the risk of recurrence and progression of non-invasive bladder cancer

Background. There is a huge number of algorithms for the diagnosis and prognosis of the clinical course of non-invasive bladder cancer (NIBC). They are based on both clinical and morphological features and data from immunohistochemical (IHC) studies in which a large number of markers, including p53, Ki-67, VEGF, E-cadherin, MMP, bcl, etc., were used. Of scientific and practical interest is a comprehensive assessment of the prognostic value of a number of the main IHC markers used for the diagnosis and prognosis of bladder cancer, the impact of epithelial-mesenchymal transition (EMT) processes and the immune response on the risk of recurrence and tumor progression. Purpose. To study the prognostic value of the panel of IHC markers for determining the risk of recurrence and progression of NIBC. Materials and Methods. We studied surgically removed stage T1 malignant bladder tumors that spread to the submucosal tissue without invasion into the muscle tissue in 42 patients. Recurrence was understood as tumor development within 5 years after surgical treatment. The term «progression» meant the growth of the tumor in the muscle tissue, in other words, transformation of the tumor from non-muscle-invasive to muscle-invasive, which is of great prognostic significance for this type of cancer. IHC study was performed using primary ready-to-use monoclonal antibodies produced by DAKO (Denmark) for p53, p63, Ki67, E-cadherin, N-cadherin, CK7, CK20, Vimentin (VimentinV9), MMP-9, TGF- β1, VEGF, CD34+, CD3+, CD4+, CD8+, CD20+, CD68+, collagen IV. Epithelial markers (E-cadherin, cytokeratins 20 (CK20) and 7 (CK7)) and mesenchymal markers (N-cadherin and vimentin) were used to study EMT processes. Statistical processing of the research results was performed using the Statistica 6.0 package. Results and Discussion. It was found that the following markers may have prognostic value for the recurrence of NIBC: p53, CD3+, CD8+, CD68+; for recurrence with progression: Ki-67 and MMP-9. As differentiation of NIBC decreased, we observed increased expression of vimentin, Ki-67, MMP-9, VEGF, CD3+, CD8+, CD68+, p53, CD 34 and decreased expression of E-cadherin, CK20, collagen IV, p63. We established a relationship between the clinical behavior of NIBC and EMT processes. Thus, stage 1 EMT was characteristic of cancer with recurrence but without progression (p < 0.05), and stage 2 EMT was characteristic of NIBC with recurrence and progression (p < 0.05). The association of EMT with immune cell infiltration of NIBC was proven. The emergence of EMT in NIBC is associated with an increase in the intensity of infiltration by CD68+ macrophages (p < 0.01), CD3+-T-lymphocytes (p < 0.05), including both CD8+ (p < 0.01) and CD4+ (p < 0.05) cells. Conclusions. Non-progressive cancer with recurrence is characterized by stage 1 EMT of the tumor cells (p < 0.05), and progressive NIBC with recurrence is characterized by stage 2 EMT (p < 0.05). The association of EMT with immune cell infiltration of NIBC was proven. The emergence of EMT in NIBC is associated with an increase in the intensity of infiltration by CD68+ macrophages (p < 0.01), CD3+ T-lymphocytes (p < 0.05), including both CD8+ (p < 0.01) and CD4+ (p < 0.05) cells.

Evidence for distinct mechanisms of immune suppression in EBV-positive and EBV-negative Hodgkin lymphoma.

Epstein Barr Virus (EBV) has been recognized for its ability to transform B lymphocytes and for its association with different types of cancers including Hodgkin lymphoma. In addition, EBV may also modulate the microenvironment of HL. In this study, we aimed to investigate the prevalence of EBV among HL cases in Ethiopia and to assess the tissue cellular composition of EBV-related and EBV-unrelated cases. We constructed a tissue microarray (TMA) of 126 consecutive cases of classical HL (CHL) and nodular lymphocyte predominant HL (NLPHL) from a tertiary cancer centre, Tikur Anbessa Hospital, Addis Ababa, Ethiopia, and evaluated a panel of immunohistochemical markers. The quantification of immune cells was performed using HALO 2.3, a platform for image analysis from Indica Lab Inc. A total of 77/126 (61.1%) of HL cases expressed LMP1/EBER. Infiltration of CD8+, T-bet+ and FoxP3+ cells was higher in the microenvironment of EBV-related CHL, with P values of <0.001, <0.001 and <0.016, respectively. In contrast, the expression of PD1 was higher in the microenvironment of EBV-unrelated CHL cases (P < 0.001). Unlike in Western countries, the majority of HL cases in Ethiopia were associated with EBV. As FoxP3+ and PD1-expressing cells are thought to participate in down regulation of the immune response by different mechanisms, this finding highlights the previously unrecognized possibility that distinct immunosuppressive mechanisms may be ongoing within EBV positive and negative HL types. This may have important prognostic and therapeutic implications.

Melan-A expression in non-melanocytic carcinoma: A potential diagnostic pitfall.

Melan-A/MART-1 is a melanocytic differentiation marker recognized as an antigen on melanoma cells. It is a useful diagnostic marker for pathologists in the diagnosis of melanocytic tumors. However, we recently found that Melan-A can be expressed in some non-melanocytic carcinomas that are rarely reported in the literature. We analyzed the expression of Melan-A in 87 non-melanocytic carcinoma tissue samples by immunohistochemistry. Marker positivity was defined as ≥10% positive tumor cells. In 87 non-melanocytic carcinoma tissue samples, Melan-A was positive in six (6.89%) cases, of which four (66.7%) were male and two (33.3%) were female, with a mean age of 60 years (range 21-82 years). Five (83.3%) of the Melan-A-positive cases had distant metastases. Compared with Melan-A negative cases, Melan-A positive non-melanocytic carcinomas were significantly associated with poor prognosis (P=0.0023). Melan-A expression is relatively rare in non-melanocytic carcinoma cases. This report highlights a potential diagnostic pitfall in the diagnosis of melanoma, urges pathologists to exercise caution in cases of Melan-A positivity, and illustrates the need for an immunohistochemical marker panel to avoid misdiagnosis.

Using digital pathology to analyze the murine cerebrovasculature

Research on the cerebrovasculature may provide insights into brain health and disease. Immunohistochemical staining is one way to visualize blood vessels, and digital pathology has the potential to revolutionize the measurement of blood vessel parameters. These tools provide opportunities for translational mouse model research. However, mouse brain tissue presents a formidable set of technical challenges, including potentially high background staining and cross-reactivity of endogenous IgG. Formalin-fixed paraffin-embedded (FFPE) and fixed frozen sections, both of which are widely used, may require different methods. In this study, we optimized blood vessel staining in mouse brain tissue, testing both FFPE and frozen fixed sections. A panel of immunohistochemical blood vessel markers were tested (including CD31, CD34, collagen IV, DP71, and VWF), to evaluate their suitability for digital pathological analysis. Collagen IV provided the best immunostaining results in both FFPE and frozen fixed murine brain sections, with highly-specific staining of large and small blood vessels and low background staining. Subsequent analysis of collagen IV-stained sections showed region and sex-specific differences in vessel density and vessel wall thickness. We conclude that digital pathology provides a useful tool for relatively unbiased analysis of the murine cerebrovasculature, provided proper protein markers are used.

Telengiectatic osteosarcoma of mandible with special emphasis on immunohistochemical and molecular characteristics: A case report with review of literature

AbstractBackgroundTelangiectatic osteosarcoma (TOS) is an uncommon pathology accounting for about 0.4%–12% of all osteosarcomas with predilection for younger adults. It is most frequently seen in the metaphysis of long bones, appearing as painful osteolytic mass that histopathologically characterized by dilated, blood‐filled vascular spaces lined by malignant osteoblasts along with osteoid formation. It has exchangeable clinical, radiological and pathological features with benign lesions like aneurysmal bone cyst and giant cell tumour of bone as well. Thus, delineating this malignancy from its benign counterparts is a crucial part in the therapeutic management.AimTo report a case of telengiectatic osteosarcoma of jaw in a 17 year old female patient with special highlights on molecular diagnostics and therapeutic modules.Materials and MethodsA panel of immunohistochemical markers comprising of SATB2, CDK4, MDM2, panCK, CD31, desmin, NKX2.2 and TLE1 were employed in combination with fluorescent in‐situ hybridization to detect the prevalence of rearrangement in CDK4 and MDM2 genes.ResultsOn immunohistochemistry, the neoplastic cells were strongly positive for SATB2 and negative for CDK4, MDM2, panCK, CD31, desmin, NKX2.2 and TLE1. Fluorescent in‐situ hybridization of CDK4 and MDM2 genes was also negative.ConclusionConsidering its rarity in jaws combined with clinicopathological overlap with other benign pathologies, diagnosis of this entity is crucial in treatment planning and prognostic significance. Moreover, only five cases of TOS have been reported so far in the craniofacial region. Here, we have reported the sixth case of its kind with detailed clarification pertaining to its immunohistochemical and molecular aspects.

Aberrant expression of GATA3 in metastatic adenocarcinoma of the prostate: an important pitfall.

The distinction of high-grade prostate cancer (PCa) from poorly differentiated urothelial carcinoma (UC) can be somewhat challenging on clinical and morphological grounds alone, yet it is of great importance for prognostication and choice of treatment. GATA3 is a useful immunohistochemical marker to confirm urothelial origin. However, recent works report strong GATA3 immunoexpression in primary high-grade PCa. The aim of this study was to explore GATA3 expression specifically in metastatic PCa. The pathology databases of four tertiary institutions were queried for cases of metastatic PCa. Available slides and clinical records were reviewed by experienced genitourinary pathologists. Prostatic markers (PSA, PSAP, NKX3.1) and GATA3 immunohistochemistry were performed. A total of 163 metastatic PCa cases were included. At least one prostate marker was positive in each case of non-regional distant metastasis, confirming prostatic origin. GATA3 strong staining was found in four (2.5%) cases: two liver, one bone and one non-regional lymph-node metastases. All four patients had Grade Group 5 PCa at the initial diagnosis. The metastatic prostatic adenocarcinomas were solid, either with no gland formation (n = 3) or with only focal cribriforming (n = 1). To our knowledge, this is the first study exploring GATA3 expression specifically in metastatic PCa. Despite being infrequent, GATA3 positivity in high-grade PCa may lead to misdiagnosis, with clinical implications. We recommend a panel of immunohistochemical markers, both prostatic and urothelial, for ruling out UC, either in primary tumour samples or in the event of metastases of unknown primary, when a genitourinary origin is suspected.

Classification of Salivary Gland Lesions on Cell Block Preparations with a Panel of Immunohistochemical Markers - a Rapid, Reliable, and Minimally Invasive Diagnostic Modality

&lt;p&gt;Fine-needle aspiration cytology (FNAC) is used as a valuable method for examining suspected salivary gland lesions. It is a simple, costeffective, and minimally invasive procedure with high specificity and sensitivity. Due to the cellular heterogeneity and overlapping architectural features, it can be difficult to distinguish between non-neoplastic processes, benign lesions, and/or malignancies in salivary glands on routine stains. Cell block methods are currently replacing surgical biopsy-based diagnostic methods on the basis of utilizing aspirates from FNAC with a rapid and reliable potential for reaching a conclusive diagnosis. Ancillary investigations including a panel of immunohistochemical markers are frequently applied on cytology specimens in the era of precision diagnostics to offer a specific diagnosis and even prognostic information for optimal patient care.&lt;/p&gt;

Utility of a PAX2, PTEN, and β-catenin Panel in the Diagnosis of Atypical Hyperplasia/Endometrioid Intraepithelial Neoplasia in Endometrial Polyps.

The diagnosis of atypical hyperplasia/endometrioid intraepithelial neoplasm (AH/EIN) within endometrial polyps (EMPs) often poses a diagnostic conundrum. Our previous studies demonstrated that a panel of immunohistochemical (IHC) markers consisting of PAX2, PTEN, and β-catenin can be effectively utilized for the identification of AH/EIN. A total of 105 AH/EIN within EMP were analyzed using the 3-marker panel. We also evaluated these cases for the presence of morules. Benign EMP (n=90) and AH/EIN unassociated with polyp (n=111) served as controls. Aberrant expression of PAX2, PTEN, or β-catenin was observed in AH/EIN in EMP in 64.8%, 39.0%, and 61.9% of cases, respectively. At least 1 IHC marker was abnormal in 92.4% of cases. Overall, 60% of AH/EIN in EMP demonstrated abnormal results for≥2 IHC markers. The prevalence of PAX2 aberrancy was significantly lower in AH/EIN in EMP than in nonpolyp AH/EIN (64.8% vs. 81.1%, P =0.007), but higher than in benign EMP (64.8% vs. 14.4%, P <0.00001). The prevalence of β-catenin aberrancy was significantly higher in AH/EIN in EMP than in nonpolyp AH/EIN (61.9% vs. 47.7%, P =0.037). All control benign EMP demonstrated normal expression of PTEN and β-catenin. Morules were present in 38.1% of AH/EIN in EMP versus 24.3% in nonpolyp AH/EIN, and absent in benign EMP. A strong positive association was found between β-catenin and morules (Φ=0.64). Overall, 90% cases of atypical polypoid adenomyoma (n=6) and mucinous papillary proliferation (n=4) showed IHC marker aberrancy. In conclusion, the 3-marker IHC panel (PAX2, PTEN, and β-catenin) is (1) a useful tool in the diagnosis of AH/EIN in EMP; (2) PAX2 loss should be interpreted with caution and in combination with morphology and other markers.

ASSESSMENT OF THE RECEPTIVITY OF THE ENDOMETRIUM TO STEROID HORMONES IN WOMEN WITH CHRONIC ENDOMETRITIS

Chronic endometritis (CE) is one of the main pathologies that lead to female infertility. Although research on the molecular and biological features of the endometrium in this disease has been conducted for a long time, the problem of studying the morphotype of CE remains relevant. Today, there is no universally accepted panel of immunohistochemical markers that would allow to fully evaluate the status of the endometrium before and after treatment, as well as to evaluate the effectiveness of the therapy. The purpose of our study was to study the features of the expression of markers of estrogen (ER) and progesterone (PR) receptors in order to make a prognosis for the recovery of patients with a possible subsequent pregnancy. For this, 2 research groups were formed using Peipel biopsies of female patients. Group I included cases before treatment, group II – after treatment. During the study, it was found that the criterion for the success of the treatment is a relative decrease of ER- and PR-positive cells both in the stroma (p&lt;0.0001) and in the epithelium of the endometrium (p&lt;0.0001). It was also found, that the expression of PR by the epithelium of the glands shouldn`t exceed 50% (p&lt;0.0001), while for ER the critical level hasn`t been established (p=0.77) and it is possible to judge only the relative decrease in the expression of the marker.

Correlation between Germinal Center Differentiation and Double/Triple Hit Score in the Classification of Diffuse Large B Cell Non-Hodgkin Lymphoma: A Clinicopathological Approach

Background: Diffuse large B cell lymphoma (DLBCL) is considered the most common type of non-Hodgkin lymphoma. The global incidence of DLBCL has been doubled in the past decades, highlighting the need for more effective treatment regimens. The curability of DLBCL is heavily influenced by a number of factors, such as the age, the international prognostic index (IPI) score, the molecular cell of origin (COO) subtype, and presence/ absence of specific chromosomal rearrangements or protein expression. Recent gene profiling studies have classified DLBCL into two main categories, germinal center B-cell type (GCB) and activated B-cell type (ABC). Validation of these subtypes has become more applicable after the immunohistochemical algorithm suggested by Hans, which included three commercially available markers, CD10, BCL6, and MUM-1/IRF4. In addition to this classification, DLBCL prognostic models based on different sets of genes or immunohistochemical markers have been proposed. More recently, DLBCLs with translocations of MYC, along with a B-cell lymphoma 2 (BCL2) and/or B-cell lymphoma 6 (BCL6) rearrangement, are now called double-hit lymphoma (DHL) or triple-hit lymphoma (THL), respectively. Furthermore, the co-expre sion of MYC and BCL2 proteins without underlying rearrangements is considered a new adverse prognostic indicator termed double-expressor lymphoma (DEL). The present study is aiming to combine morphological, immunophenotypical, and genetic features of DLBCLs to reach a more reproducible subtyping. Aim: To identify the relation between clinicopathological features as patient age, sex, site of tumor, clinical presentation and tumor stage and the germinal center differentiation in DLBCL (germinal center B-cell (GCB) or activated B-cell (ABC)) and the double/triple genetic hits status.Material and Methods: The material of this study comprised 52 formalin-fixed paraffin- embedded blocks representative of diffuse large B cell lymphoma cases retrieved from the archival material available at the Pathology Department, Faculty of Medicine, Alexandria University. Subclassification of cases into (germinal center / and post-germinal center types) using a panel of immunohistochemical markers including CD10, BCL6 and MUM1 was done and scoring of double/triple hit expression using a panel of immunohistochemical markers including c-MYC, BCL6 and BCL2 was also done and correlation with their subtypes and clinical data was performed.Results: there was significant association between germinal center differentiation and tumor stage (MCp= 0.018).Conclusion: Germinal center differentiation status is a valid method to evaluate the prognosis of DLBCL.

Primary leiomyosarcoma of tongue: A relatively uncommon entity occurring at an exceedingly rare site

Primary leiomyosarcoma (LMS) of the tongue is an extremely rare, highly aggressive malignancy associated with poor survival outcome. We report a case of 60 years old male who presented with growth left lateral border of tongue since 6 months. Histopathological examination of the excised growth confirmed the diagnosis of LMS. An exhaustive panel of immunohistochemical markers helped in ruling out other malignant spindle cell differentials.

Identification and validation of immunohistochemical marker panels to predict the prognosis of muscle invasive bladder cancer.

Currently, the treatment regimen of bladder cancer depends on the stage and grade. Yet, patients with similar histopathological characteristics may have distinct prognosis. Luminal/basal subtyping had proved to be a satisfactory subtyping method. Here we intended to evaluate immunohistochemistry, a more clinically-practical method, in luminal/basal classification and further risk-stratification. Patients diagnosed with urothelial carcinoma of the bladder in Changhai Hospital were retrospectively recruited and corresponding formalin-fixed paraffin embedded blocks were acquired. Tissue microarrays (TMAs) of these patients were established followed by immunohistochemical (IHC) staining of 14 markers. Patients were classified into luminal or basal subtype according to CK5/6, CK14, CK20 and GATA3 expression. Further subtyping of luminal and basal tumors was performed according to the expression of other markers. A total of 236 patients were included: 163 and 73 patients were assigned to training and validation cohorts, respectively. Patients with basal tumor were related with poorer prognosis compared to those with luminal tumor (P=0.025 and 0.008 in training and validation cohorts, respectively). We further revealed luminal muscle invasive bladder cancer (MIBC) patients could be further categorized into subgroups with different risks. Cytoplasmic YAP1 and CCNB1 were selected as classifier, patients with low expression of cytoplasmic YAP1 or CCNB1 were independent risk factor for poorer prognosis (hazard ratio =2.19, P=0.04). Molecular subtyping into luminal/basal subtype and risk stratification method using a 2-marker method by immunohistochemistry can be an economical, clinically practical method to predict patient prognosis and could help to develop treatment strategy and follow-up schedule in clinical practice.

Cytohistopathological Association and the Use of a Dual Immunohistochemical Regimen in the Diagnosis of Lung Malignancies: A Cross-sectional Study

Introduction: Lung cancer is a highly aggressive malignancy that causes significant morbidity and mortality. The incidence of lung cancer has been increasing in the past few decades. Cytology aids in the initial evaluation and diagnosis of patients with lung cancer. Currently, the classification of lung carcinoma has expanded beyond small cell lung carcinoma and Non-Small Cell Lung Carcinoma (NSCLC). Precise subtyping of poorly differentiated NSCLC into adenocarcinoma and Squamous Cell Carcinoma (SCC) has a direct impact on patient management and prognosis. The morphologic diagnosis forms the basis and is further supplemented by a panel of immunohistochemical markers. Immunohistochemistry (IHC) is important in cases with poorly differentiated morphology or partial sampling. The IHC panel used includes Tumour Protein p63 (p63) and Thyroid Transcription Factor (TTF1) for subtyping lung cancer. Aim: The present study was conducted with the aim of studying the age and gender distribution, risk factors, cytohistopathological association, and formulating an effective IHC panel for the precise yet effective subtyping of poorly differentiated lung malignancies. Materials and Methods: This cross-sectional study included cases retrieved from the Archives of Pathology Department, SRM Medical College and Research Centre, Chennai, Tamil Nadu, India, between July 2012 and July 2016. The cases included had a diagnosis of lung malignancy (confirmed by cytology/biopsy) or were suspected of having malignancy based on clinical/radiological findings. The study period was from July 2015 to August 2016. The cytology and biopsy slides were reviewed, and the malignancy was classified according to the World Health Organisation (WHO) classification of lung malignancies (2021). IHC was performed on the cases using the markers p63 and TTF1 as a dual regimen. Diagnosis and subtyping of tumours were done based on histomorphology, and the tumours were reclassified based on IHC findings. The data were statistically analysed using SPSS software version 25 and the ROC curve. Results: The mean age of the patients was 60.9 years. The study included a total of 50 cases of lung carcinoma, with an average age of 60.9 years (ranging from 30 to 88 years). Among the cases, 35 (70%) had a positive smoking history. A concordant cytohistopathological association was observed in 26 (52%) of cases. Adenocarcinoma was the predominant subtype, accounting for 21 (42%) of cases. Tumour cells in adenocarcinoma showed positive staining for TTF-1, with the marker exhibiting 100% sensitivity and 83% specificity. In SCC, tumour cells were positive for p63, with the marker demonstrating 92% sensitivity and 82% specificity. Both markers showed effective sensitivity and specificity when used as a dual regimen. Conclusion: Although lung cancer is typically diagnosed in the elderly population, there has been an increase in cases among younger individuals due to urbanisation. Smoking remains an important risk factor for lung malignancy. Exfoliative cytology alone is not sufficient for the diagnosis of lung malignancies and should be supplemented with biopsy for more accurate results. Adenocarcinoma was found to be the most common subtype in our study. The IHC panel of p63 and TTF-1 proved to be an effective regimen for classifying poorly differentiated lung carcinomas.

Utility of GATA-3 and associated immunohistochemical markers in the differential diagnosis of poorly differentiated urothelial carcinoma.

The aims are to study the utility of GATA-3 along with panel of immunohistochemical (IHC) markers in the differential diagnosis of primary and metastatic poorly differentiated urothelial carcinoma (UC). This is a prospective and retrospective observational study. Poorly differentiated carcinomas of urinary tract and metastatic sites from January 2016 to December 2017 were subjected to a panel of four IHC markers including GATA-3, p63, Cytokeratin (CK) 7, and CK20. Additional markers such as p16, an enzyme called alpha-methylacyl-CoA racemase, CDX2, and thyroid transcription factor 1 were also done depending on the morphology and site. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of GATA-3 in making the diagnosis of UC were calculated. Forty-five cases were included in the study and after appropriate IHC, the diagnosis was resolved as UC in 24 cases. GATA-3 was positive in 83.33% of UC; all the four markers positive in 33.33% and all negative in 4.17% of UC. However, at least one of the four markers was present in 95.83% of UC, except in sarcomatoid UC. GATA-3 had 100% specificity in differentiating from prostate adenocarcinoma. GATA-3 is a useful marker in the diagnosis of UC in the primary and metastatic sites with a sensitivity of 83.33%. GATA-3 along with other IHC markers in correlation with clinical and imageological features is necessary for making specific diagnosis of poorly differentiated carcinoma.

A Case of Tubular Carcinoid of the Appendix: A Rare Entity

Carcinoid tumours of the appendix are low-grade neoplasms with neuroendocrine differentiation. They are typically found incidentally during appendectomies. Tubular carcinoid is an extremely rare, distinct, and benign form of appendiceal carcinoid. Here, we present the case of a 32-year-old male who presented with an abdominal mass and pain radiating to the right iliac fossa. Appendectomy was performed, and the gross examination revealed a congested and exudate-covered appendix. Microscopic analysis showed small tubules infiltrating the appendix wall, along with evidence of acute appendicitis. Differential diagnoses considered included carcinoid tumour with glandular differentiation and metastatic adenocarcinoma. Additional sections were examined, and a final diagnosis of tubular carcinoid was made after conducting a panel of immunohistochemical markers and Alcian blue stain. Since most tubular carcinoids are not identifiable on gross, microscopic assessment and serial sectioning play a crucial role in diagnosing this condition.

Role of Morphology and Immunohistochemistry in the Diagnosis of Incidental Cancers in Gallstone Disease

Introduction: The majority of gallbladder adenocarcinomas have been known to develop from dysplasia or carcinoma in situ, without pre-existing adenomas, hence observation of these non-neoplastic or preneoplastic lesions is important as it may underlie an occult malignancy. To study the role of morphology and immunohistochemistry in the diagnosis of incidental cancers in cases of gall stone disease by adopting a universal histopathological screening policy for all the gallstone disease cases operated at our tertiary care center. Material and Methods: The present study was designed as an observational cross sectional study completed over a time period of 14 months. A total of 176 cases were included in the study including all the patients of gall stone disease in the adult age group. All the indeterminate and frankly malignant cases were subjected to immunohistochemistry with a panel of antibody markers including p53, CEA and Ki-67 using Streptavidin Biotin immunoperoxidase method Fisher-exact test was used to compare the data taking‘p’ value less than 0.05 as statistically significant. Results: Mean age of patients was 40.55±13.25 years. Majority of patients (n=141; 80.1%) were females. The final diagnosis revealed a dominance of non-neoplastic inflammatory (n=168; 95.5%) pathology. There were 8 (4.5%) of malignancy, of these 7 were adenocarcinoma and 1 was adenosquamous carcinoma. Atypia was seen in 5 (2.8%) cases and 3 (1.7%) cases were of dysplasia. Histopathology detected carcinoma in 7 (4%) cases whereas addition of immunohistochemistry helped to find out one more unidentified case, thus the diagnostic yield increased to 8 (4.5%) cases. Out of three dysplasia cases, one (33.3%) was found positive on immunohistochemistry, which was later confirmed to be malignant. None of the cases of atypia were positive on p53, Ki-67 and CEA immunohistochemistry. On comparison between the three groups, the results were statistically significant (p=0.00062). Conclusion: Immunohistochemistry has a useful role in detection of incidental gallbladder carcinoma when morphology is limited by indeterminate results. A panel of immunohistochemical markers including p53, Ki-67 and CEA may prove very useful to pick up cases of malignancy in such cases of diagnostic dilemma.

Correlation of PD-L1 immunohistochemical expression with microsatellite instability and p53 status in endometrial carcinoma.

Endometrial carcinoma (EC) is the most common gynaecological cancer worldwide. The Cancer Genome Atlas molecular grouping of a given case of EC could be assessed by POLE gene mutation, mismatch repair (MMR) 'to reflect microsatellite instability' and p53 status, which has proved to be of prognostic value. Programmed cell death receptor 1 (PD-1) and its ligand (PD-L1) are playing a progressively important role in tumour immunology and cancer treatment. To investigate PD-L1 immunohistochemical expression in EC in relation to MMR and p53 status. Associations between marker expression and different histopathological parameters were also investigated. This retrospective study was performed on archival biopsies of 170 cases of EC using a tissue microarray model. Immunohistochemical staining was applied using antibodies against PD-L1, MLH1, MSH2 and p53. The percentages of positivity were as follows: PD-L1, 19.6%; MLH1, 79.5%; MSH2, 78.5%; and p53 mutant, 13.8%. There was significant correlation between MLH1 expression and MSH2 expression (p=0.008). Tumour grade was significantly correlated with stage (p=0.005) and p53 mutant expression (p=0.008). Combined PD-L1 positivity and MMR deficiency showed significant correlation with the presence of lymphovascular space invasion (p=0.014). MSH2 negativity was significantly associated with poorer overall survival (p=0.014). A panel of immunohistochemical markers (PD-L1, MLH1, MSH2 and p53) could help to predict the prognosis and plan the treatment of patients with EC. MMR deficiency seems to be a good predictor for PD-L1 status, and therefore the response to potential PD-1/PD-L1 inhibitor therapy.

The "hypopigmented" bitemark: a clinical and histologic appraisal.

So-called "hypopigmented" bitemark patterns, commonly seen but not limited to dark skinned individuals, can be of value in forensic investigations. The process of aging bitemarks observed on skin is controversial and without guidelines. This report analyzes tissue obtained from the site of a hypopigmented bitemark using special histochemical stains for the identification of melanin pigment, and a panel of immunohistochemical markers to aid in the aging process. Histologic evaluation clearly showed that cellular changes in the hypopigmented area were indicative of wound healing that had taken place over a period of time. This validates the hypothesis that a hypopigmented bitemark is an indication of a wound inflicted some days previously. These findings have value in forensic investigations, particularly in cases of suspected long-term physical abuse.