Applied Immunohistochemistry & Molecular Morphology最新文献

Odontogenic cysts are a diverse group of pathologic entities with different proliferation potential, leading to variations in their biological behavior. One of the most cited proliferation markers used in diagnostic histopathology is Ki-67. Another group of proteins recently investigated is minichromosome maintenance (MCM-3) and its expression has been evaluated in several odontogenic lesions but the results were controversial. Thus, the present study endeavored to compare the expression of MCM-3 and Ki-67 in odontogenic cysts. Furthermore, a pioneer attempt was made to evaluate the sensitivity of these markers to inflammation. A total of 101 cases (37 dentigerous cysts, 37 odontogenic keratocysts, and 27 radicular cysts) were included. Immunohistochemical expression of Ki-67 and MCM-3 were investigated using a labeling index (LI). In addition, they were scored for inflammation, followed by correlation with both markers. The data obtained were subjected to statistical analysis ( P <0.05). Overall, a higher LI of MCM-3 than Ki-67 was obtained in all study groups along with a positive correlation of Ki-67 LI with inflammation. Thus, MCM-3 proteins proved to be a more accurate means to determine the proliferation potential and were not sensitive to external stimuli like inflammation than conventional markers, such as Ki-67.

Arginase-1 (Arg1) and hepatocyte paraffin antigen 1 (HepPar1) are specific and sensitive markers of hepatocellular differentiation. HepPar1 is a granular cytoplasmic immunostain that may be negative in hepatocellular carcinoma (HCC) with cytoplasmic clearing. Arg1 shows uniform cytoplasmic positivity and frequent nuclear positivity. This study was undertaken to determine the staining pattern of Arg1 in HCC with cytoplasmic clearing and compare its use to HepPar1. Fifteen resected HCCs with cytoplasmic clearing and 31 biopsies of clear cell liver tumors (14 HCCs and 17 nonhepatocellular tumors) were identified. Resections were stained with Arg1 to characterize the pattern, intensity, and extent of Arg1 positivity. Biopsies were stained with Arg1 (n=31) and HepPar1 (n=28). In all, 13/15 resected and 11/14 biopsied HCCs with cytoplasmic clearing showed nuclear positivity for Arg1. Both Arg1 and HepPar1 stained significantly more HCCs than nonhepatocellular tumors (13/14 and 11/12, respectively, with P <0.0001 and P =0.0018, respectively). However, HepPar1 stained significantly more nonhepatocellular tumors (5/12) than Arg1 (0/17, P =0.0445). Arg1 frequently displayed nuclear positivity, and interobserver agreement was better for Arg1 ( K =0.93 vs. 0.79). Overall, Arg1 is more specific than HepPar1 for differentiating HCC with cytoplasmic clearing from nonhepatocellular clear cell tumors in the liver. Its staining characteristics, including nuclear positivity, make it easier to interpret in combination with morphology, improving interobserver variability, and it stains significantly fewer mimics than HepPar1.

Objectives: Lung adenocarcinoma (LUAD) is a critical cancer with high mortality, worse prognosis, and crucial lymphatic metastasis. Consequently, prognostic biomarkers for LUAD are truly required. β-Ureidopropionase (UPB1) is abnormally expressed in various cancers. However, the function of UPB1 in LUAD is still ambiguous. This study aimed to explore the expression profile and prognostic significance of UPB1 in LUAD.

Materials and methods: The differential UPB1 levels in pan cancers and their prognostic significance were comprehensively investigated through Gene Expression Profiling Interactive Analysis, UALCAN, Tumor Immune Estimation Resource, and Kaplan-Meier plotter platform. The correlation between UPB1 and tumor infiltration immune cells was explored using Tumor Immune Estimation Resource, Gene Expression Profiling Interactive Analysis, and Tumor-Immune System Interactions and Drug Bank database databases.

Results: The UPB1 level was abnormally expressed in pan-tumor tissue than in adjacent tissue from The Cancer Genome Atlas tool. Low UPB1 level was correlated with poor overall survival in patients with LUAD. Furthermore, a comparison of the various pathologic characteristics of LUAD between high and low UPB1 level subgroups revealed that low UPB1 expression was correlated with lymph node metastasis. Kaplan-Meier survival analysis indicated that a low UPB1 level was associated with worse progression‑free survival and overall survival in patients with LUAD. Univariate and multivariate analyses suggested that UPB1 could be a useful prognostic indicator for LUAD. Abnormal UPB1 may be correlated with aberrant LUAD immune infiltration, prompting a worse survival outcome.

Conclusions: Results showed that low UPB1 is correlated with a worse prognosis of LUAD and may be a valuable prognostic indicator for LUAD.

Diffuse large B-cell lymphoma (DLBCL) represents the most common subtype of non-Hodgkins lymphoma. After the introduction of rituximab therapy like rituximab, cyclophosphamide, doxorubicin vincristine, prednisolone, there has been considerable improvement in the 5-year overall survival in this group of patients, but the nonresponding patients are a challenge to the clinician. The translesion polymerases are unique polymerases that make cells tolerant to DNA damage. Many point mutations are introduced owing to their inherent property of bypassing the points of lesions, preventing the cell from stalling replication. However, the impaired activity of these polymerases can lead to the development of tumors with aggressive clinical course. In this study, the gene expression levels of polymerase eta ( POLE ) were compared in 2 cohorts of patients with DLBCL: the first cohort, patients who had achieved complete response, and the second cohort, patients who were refractory to the treatment or had relapse within 2 years of treatment. There was a significantly upregulated expression in the refractory/relapse cohort compared with the complete remission cohort ( P = 0.0001). The high POLE expression levels correlated significantly with advanced disease stages (III and IV) and poor disease-free survival in the Kaplan-Meier curve. The high POLE expression levels were correlated with poor disease-free survival in nonresponder patients with DLBCL. The results concluded that patients with DLBCL with a high polymerase gene expression may show nonresponsiveness to chemotherapy; hence the functional impact of upregulated expression of POLE in DLBCL requires an in-depth assessment.

Analytical verification and validation of immunohistochemical (IHC) tests and their equipment are common practices for today's anatomic pathology laboratories. Few references or guidelines are available on how this should be performed. The study of Sciensano (the Belgian national competent authority regarding licensing of medical laboratories) performed in 2016, demonstrated a significant interlaboratory variation in validation procedures of IHC tests among Belgian laboratories. These results suggest the unavailability of practical information on the approach to the verification and validation of these tests. The existing Belgian Practice Guideline for the implementation of a quality management system in anatomic pathology laboratories has been reviewed to meet this demand and, in addition, to prepare the laboratories for the EU-IVD revised regulations (IVDR). This paper describes Belgian recommendations for the verification and validation of IHC tests before implementation, for ongoing validation, and for revalidation. For each type of test (according to the IVDR classification and the origin) and its intended use (purpose), it addresses how to perform analytical verification/validation by recommending: (1) the number of cases in the validation set, (2) the performance characteristics to be evaluated, (3) the objective acceptance criteria, (4) the evaluation method for the obtained results, and (5) how and when to revalidate. A literature study and a risk analysis taking into account the majority of variables regarding verification/validation of methods have been performed, resulting in an expert consensus recommendation that is a compromise among achievability, affordability, and patient safety. This new consensus recommendation has been incorporated in the aforementioned ISO 15189:2012-based Practice Guideline.

Recently, the US Food and Drug Administration (FDA) approved the Ventana MMR RxDx Panel as the first immunohistochemical companion diagnostic test for identification of tumors with mismatch repair (MMR) status. The aim of this study was to investigate the accuracy of this test in comparison with polymerase chain reaction (PCR)-based microsatellite instability (MSI) analysis. We assessed the MMR/MSI concordance rate in 140 cases of endometrioid carcinoma. MMR status was evaluated by immunohistochemistry (MMR-IHC), and MSI status was evaluated by PCR-based analysis (MSI-PCR). Potential molecular mechanisms responsible for MSH6 staining variations were also analyzed. Immunohistochemistry showed that 34 tumors (24.3%) were MMRd; these included 26 with combined MLH1/PMS2 loss, 2 with combined MSH2/MSH6 loss, and 6 with isolated MSH6 loss. Heterogeneous MSH6 loss was found in 10 tumors and was recognized only in tumors with combined MLH1/PMS2 loss. Eight of 10 tumors with heterogeneous MSH6 loss harbored MSH6 C8 tract instability, suggesting a secondary somatic event after MLH1/PMS2 loss. MSI-PCR revealed that 102 tumors were MSS, 4 were MSI-low, and 34 were MSI-high. Consequently, MMR-IHC and MSI-PCR showed perfect concordance (kappa=0.080, P <0.0001). However, 10 of the 34 MSI-high tumors, including the 6 tumors with isolated MSH6 loss, showed only minimal microsatellite shift by MSI-PCR, which may have been erroneously interpreted as MSS or MSI-low. On the basis of these findings, we consider that the FDA-approved immunohistochemical panel can detect MMR variations consistently and is more accurate than MSI-PCR for determining the applicability of immune checkpoint inhibitors for treatment of endometrioid carcinomas.

Pathologists diagnose diseases by observing the histologic and cellular morphology microscopically. However, the high pigmentation in melanin-containing tumors can hide the tumor cell structures, making diagnosing challenging. Previously, hydrogen peroxide and potassium permanganate were utilized for melanin bleaching with several limitations. For instance, hydrogen peroxide has a weak bleaching ability, and the process is time-consuming (12 h). Meanwhile, potassium permanganate affects the antigenicity of antigens and is unsuitable for immunohistochemical (IHC) staining. In this study, the hypochlorous acid (HClO) solution was applied to hematoxylin-eosin and IHC staining of melanin tissue sections. The study discovered that 1% HClO could completely bleach melanin particles in tumor tissues in a short period (19.95 ± 2.53 min) without compromising the hematoxylin-eosin staining. In addition, 2% HClO was utilized for bleaching at room temperature for 61.17 ± 4.32 minutes after the tissue was incubated with 3,3'-diaminobenzidine in IHC staining. This treatment effectively removed melanin without negatively impacting 3,3'-diaminobenzidine signal expression, thus ensuring that the sections met the necessary diagnostic requirements. Therefore, this method could facilitate pathologists in disease diagnosis of melanin-containing tissues.

The clinical utility of the proliferation marker Ki67 in breast cancer treatment and prognosis is an active area of research. Studies have suggested that differences in pre-analytic and analytic factors contribute to low analytical validity of the assay, with scoring methods accounting for a large proportion of this variability. Use of standard scoring methods is limited, in part due to the time intensive nature of such reporting protocols. Therefore, use of digital image analysis tools may help to both standardize reporting and improve workflow. In this study, digital image analysis was utilized to quantify Ki67 indices in 280 breast biopsy and resection specimens during routine clinical practice. The supervised Ki67 indices were then assessed for agreement with a manual count of 500 tumor cells. Agreement was excellent, with an intraclass correlation coefficient of 0.96 for the pathologist-supervised analysis. This study illustrates an example of a rapid, accurate workflow for implementation of digital image analysis in Ki67 scoring in breast cancer.

Substantial diminution or loss of GATA3 expression is reportedly frequent in human papillomavirus-independent (HPVI), p53-mediated vulvar intraepithelial neoplasia. Herein, we study GATA3 expression in vulvar squamous cell carcinoma (VSCC) and assess its clinicopathologic significance. Eighty-six cases of VSCC diagnosed at a single institution were immunohistochemically assessed for their expression of GATA3, as well as any possible relationships with patient outcomes and other clinicopathologic parameters. Given that GATA3 expression pattern in the normal vulvar epidermis is typically strong basal staining with a uniform upward extension until at least the mid epidermal layers, VSCCs were scored using a previously reported tripattern system: pattern 0 (>75% tumor staining), pattern 1 (25% to 75% staining), and pattern 2 (<25% staining). Severe loss of GATA3 expression (pattern 2) was present in both human papillomavirus-associated (HPVA) and HPVI VSCC but was significantly more common in HPVI cases ( P <0.001). Among 52 HPVA VSCCs, 16 (30.7%), 15 (28.8%), and 21 (40.3%) cases showed patterns 0, 1, 2 staining whereas among 34 HPVI VSCCs, the respective frequencies were 1 (2.9%), 5 (14.7%), and 28 (82.3%). None of the 30 p53 abnormal VSCCs showed pattern 0 staining (0%). Five (16.6%) and 25 (83.3%) showed patterns 1 and 2 staining, respectively. On univariate analysis, the pattern 2 cohort showed a significantly worse overall survival (OS) and disease-free survival (DFS) than the pattern 0 or 1 cohort ( P =0.011 and 0.024, respectively), but this finding was not independent of stage on multivariate analysis ( P =0.34; hazard ratio: 1.82; 95% CI: 0.55-6.06). Subgroup analysis of the p53 wild-type cases showed significantly worse OS for pattern 2 than the pattern 0 or 1 cohorts, independent of stage ( P =0.04; hazard ratio: 6.5; 95% CI: 1.08-39.8). Subgroup analysis of p53 abnormal cases, however, showed no difference in OS and DFS among the 3-tiered GATA3 cohorts. In summary, loss of GATA3 may be seen in both HPVA and HPVI VSCCs but is significantly more common in HPVI SCCs. Loss or substantial diminution of GATA3 expression (pattern 2) is a negative prognostic factor in vulvar SCCs, but only in the p53 wild-type subset, where its negative prognostic significance appears to be independent of stage.

Corneal dystrophies are hereditary diseases affecting the corneal tissue; they are bilateral, symmetrical and unrelated to environmental or systemic conditions. Congenital corneal stromal dystrophy is a very rare autosomal dominant dystrophy that is caused by a mutation in the DCN gene that encodes decorin (a proteoglycan of the extracellular matrix). We herein report 4 cases of congenital stromal corneal dystrophy in 2 families, highlighting the previously undescribed histopathologic features, the possible differential diagnosis of this entity and the key role played by decorin staining in its diagnosis.