Applied Immunohistochemistry & Molecular Morphology最新文献

Tumors of the lung with a spindle cell morphology require consideration of many entities in the differential diagnosis, including metastases. Ancillary immunohistochemical stains but also molecular studies are typically required to arrive at the proper diagnosis. We present a case of a 71-year-old woman with multiple lung nodules, mediastinal lymphadenopathy, and a history of uterine cancer who underwent endobronchial ultrasound-guided fine needle aspiration and biopsy of the lung and mediastinal lymph nodes. A sampling of the lung lesion showed a cytologically bland neoplasm with spindle cell morphology, lacking necrosis or brisk mitotic activity. In conjunction with the cytomorphology, strong and diffuse Transducin-like enhancer of split 1 (TLE1) reactivity in the tumor cells initially raised the diagnosis of synovial sarcoma; however, subsequent results of additional testing showed strong and diffuse expression with AE1/AE3, CK 8/18, TTF-1, synaptophysin and chromogranin and focal or negative staining with a large number of other antibodies. This warranted a diagnosis of a carcinoid tumor. This is the first report of TLE1 staining in a carcinoid tumor of the lung. Therefore, when evaluating tumors of the lung with spindle cell morphology in which the differential diagnosis may include both carcinoid tumor and synovial sarcoma, TLE1 expression should be interpreted with caution and in conjunction with an expanded immunohistochemical staining panel.

Background: Uremic pruritus is an irritating symptom for patients with end-stage kidney disease. Lipocalin-2 (LCN2) has relevant importance in several biological cellular processes and immunity. It is also a major player in the progression of many disorders, such as renal injury.

Aim: To evaluate LCN2 expression in chronic kidney disease (CKD) pruritic patients in serum together with immunohistochemical expression in skin samples and further correlation of their results with the studied clinicopathologic parameters.

Materials and methods: Serum level of LCN2 (assessed by enzyme-linked immunosorbent assay) and skin immunohistochemical expression were investigated in 25 CKD patients and 25 healthy controls. Ten patients were subjected to narrowband ultraviolet B phototherapy for 12 weeks then re-evaluated for serum and tissue LCN2 after therapy.

Results: LCN2 expression was increased significantly in both the epidermis and dermal adnexa in CKD patients over controls. Also, serum LCN2 level was higher in patients than in healthy subjects and was significantly associated with itching severity, grades of CKD, urea, and creatinine serum level. Tissue and serum levels of LCN2 were significantly diminished in CKD patients following narrowband therapy along with improvement of the severity of pruritus.

Conclusions: The increased serum and tissue LCN2 expression in CKD pruritic patients and its pronounced decrease, in addition to the improvement of pruritus after treatment, suggest a major pathogenic role of LCN2 in uremic pruritus.

Liver transplantation (LT) is a good therapeutic decision, cures hepatocellular carcinoma (HCC) and promotes survival of cases with unrespectable HCC based on the Milan criteria. HCC still recur after LT. Identifying high risk tissue markers that predict recurrence becomes important for LT decision-making. Little is known regarding use of tissue expression of epithelial cell adhesion molecule (EpCAM) to predict HCC recurrence. This study investigates the role of EpCAM, Ki67, and endothelial-cell-specific molecule-1 (ESM1) as immunohistochemical markers to predict HCC recurrence after LT. It included 52 explanted HCC tissues from Egyptian patients who had undergone LT for HCC according to Milan criteria. Immunohistochemical staining was done on paraffin-embedded formalin-fixed tissue sections. HCC recurrence occurred in 13.5% cases. Positive EpCAM expression in HCC, was significantly associated with HCC recurrence, ( P =0.011), achieving 71.43% sensitivity, 84.44% specificity and 78.8% accuracy in predicting recurrence. High Ki67 percentage was significantly associated with HCC recurrence, ( P =0.005), achieving 57.14% sensitivity, 86.67% specificity and 82.69% accuracy in predicting HCC recurrence. ESM1 showed significant association with HCC recurrence ( P =0.041), with 71.43% sensitivity, 71.11% specificity and 71.15% accuracy in predicting HCC recurrence. EpCAM score and Ki67 percentage showed positive correlation. In conclusion, it is suggested that large tumor size (≥3 cm), advanced pathologic staging and Ki67 could be stratified as high risk predictors of HCC recurrence after LT. Although higher classes of Child-Turcotte-Pugh classification, high serum alpha-fetoprotein, microvascular invasion, positive EpCAM and ESM1 are stratified as lower risk predictors of HCC recurrence after LT.

Introduction: The Peritoneal Regression Grading Score (PRGS) is a 4-tied histologic regression grading score for determining the response of peritoneal metastasis to chemotherapy. Peritoneal biopsies in every abdominal quadrant are recommended. A positive therapy response is defined as a decreasing or stable mean PRGS between 2 therapy cycles. The added value of periodic acid satin (PAS) and Ber-EP4 staining over HE staining for diagnosing PRGS1 (the absence of vital tumor cells) is unclear.

Materials and methods: A total of 339 biopsies obtained during 76 laparoscopies in 33 patients with peritoneal metastasis of gastric cancer were analyzed. Biopsies classified as PRGS 1 (no residual tumor, n=95) or indefinite (n=50) were stained with PAS, and remaining indefinite or PRGS1 cases additionally stained with BerEP4.

Results: After PAS-staining tumor cells were detected in 28 out of 145 biopsies (19%), the remaining 117 biopsies were immunostained with Ber-EP4. Tumor cells were detected in 22 biopsies (19%). In total, additional staining allowed the detection of residual tumor cells in 50 out of 339 biopsies (15%) and changed the therapy response assessment in 7 out of 33 (21%) patients.

Conclusions: In summary, 25% (24 out of 95) of initially tumor-free samples (PRGS1) showed residual tumor cells after additional staining with PAS and/or BerEp4. Immunohistochemistry provided important additional information (the presence of tumor cells) in 22 of all 339 biopsies (11.2%). Further staining reduced the instances of unclear diagnosis from 50 to 0 and changed the therapy response assessment in 7 out of 33 patients (21%). We recommend additional staining in PRGS1 or unclear cases.

Antibodies targeting programmed death receptor 1 or programmed death ligand 1 (PD-L1) have become a standard of care to treat different cancers; for some of these tumors, there is a correlation between tissue expression of PD-L1 and response rates in patients. Although most of the analytical challenges in the evaluation of PD-L1 expression have been standardized, preanalytical issues have been less explored. The objective of this study was to evaluate the impact of time of ischemia on the performance of 2 commonly used antibodies against PD-L1. Sixteen tonsillectomy samples were kept in ischemia for <30 minutes from sample obtention (control) and 1, 3, 6, 12, and 24 hours at room temperature before formalin fixation and paraffin embedding. Selected areas were inserted into TMA paraffin recipient blocks stained with SP142 and SP263 antibodies and evaluated by 2 blind observers. The proportion of suboptimally stained samples was significantly higher for samples with cold ischemia times 6 hours or over ( P <0.0001). False-negative results were 25% in samples exposed to 6 hours of ischemia and raised to 34% for samples remaining in ischemia for 12 or 24 hours. When all observations were pooled, SP142 provided suboptimal results in 24% of observations and SP263 in 12.5%; this is a statistically significant difference ( P =0.042). In conclusion, the quality of staining for PD-L1 in tonsil samples varies with the time of cold ischemia. The SP142 antibody presented a significantly lower tolerance to prolonged cold ischemia than SP263. These results reveal the relevance of controlled preanalytical processing of samples.

Subtyping hepatic adenomas is important for patient management due to differing complication risks. Immunohistochemical staining with C-reactive protein (CRP) and serum amyloid-A (SAA) is widely accepted as a surrogate for molecular classification to identify inflammatory hepatocellular adenomas. Limited data, however, has been published on how these 2 stains compare for sensitivity. We conducted a large, multicenter, retrospective study to examine the sensitivity and staining characteristics of CRP and SAA in inflammatory hepatic adenomas, with focal nodular hyperplasia (FNHs) as a control group. Inflammatory adenomas were identified in 133 patients (average age 37 years, 109 were female). In all, 69.9% of cases were resection specimens and 90.2% of all cases showed positive staining for both CRP and SAA; 10 (7.5%) were positive for CRP only and 3 (2.3%) were positive for SAA only. CRP was more sensitive than SAA (97.74% vs. 92.48%, P -value = 0.0961) and showed more extensive and intense staining, with a significantly higher modified H-score ( P <0.001). Focal nodular hyperplasia can also show positive CRP and SAA staining but with a lower modified H-score ( P <0.0001). Based on beta-catenin and glutamine synthetase staining, 26 of inflammatory adenomas also had beta-catenin activation (19.5%). All 3 cases with positive SAA and negative CRP staining were beta-catenin activated. In contrast, the proportion of cases that were CRP positive and SAA negative was similar regardless of beta-catenin activation. The data affirms the strategy of using both CRP and SAA immunostains for hepatic adenoma subtyping and raises the awareness of the highly variable nature of SAA staining characteristics.

Multiple studies have demonstrated prostate-specific membrane antigen (PSMA) expression in the neo-vasculature of non-prostate tumors including clear cell renal cell carcinoma (ccRCC). However, PSMA expression in rare renal tumors including MiTF family translocation renal cell carcinoma has not been previously characterized. We examined PSMA expression by immunohistochemistry in a series of MiTF family translocation renal cell carcinomas as well as in several genetically related tumors including alveolar soft part sarcoma and PEComas with TFE3 rearrangements. PSMA expression was also studied in several cases of ccRCC and papillary RCC. Overall, PSMA immunohistochemistry was performed in 61 samples from 58 patients. Vascular PSMA expression was seen with the highest frequency in ccRCC [88% (14/16)] (38% focal, 50% diffuse). Translocation RCC (tRCC) demonstrated the second highest frequency of PSMA expression [71% (22/28)] (57% focal, 14% diffuse), followed by alveolar soft part sarcoma [50% (4/8)] (38% focal, 12% diffuse). No PSMA expression was seen in PEComas with TFE3 rearrangement (0/3) or papillary RCC (0/6). PSMA expression was only present in tumor-associated neo-vasculature. A patient with oligometastatic tRCC underwent 68 Ga-PSMA-11 PET imaging which detected multiple putative metastatic lesions not detected on conventional computed tomography imaging performed 2 weeks prior, supporting the potential utility of PSMA imaging in tRCC. These findings have potential implications for the utility of PSMA guided diagnostic and therapeutic agents in both common and uncommon renal cell carcinoma subtypes as well as genetically related mesenchymal neoplasms.

Primary focal segmental glomerulosclerosis (FSGS) is a type of chronic renal disease that commonly progresses to renal failure as the treatments are not particularly effective. Glomerular podocyte injury and loss are pivotal to the pathogenesis of FSGS. This study aims to explore the glomerular immunohistochemistry stain expression of Wilms tumor-1 (WT-1) (podocyte-specific protein), transforming growth factor beta (TGF-β) (cytokine protein), vascular endothelial growth factor (VEGF) (angiogenic protein), and endothelin-1 (ET-1) (profibrotic growth factor), in rats with adriamycin nephropathy, which represents the murine model of human FSGS. By the end of 8 and 12 weeks, the kidneys of adriamycin-treated rats and control rats were harvested and the histomorphology was studied. Both 8- and 12-week test groups developed proteinuria, and hypoalbuminemia and showed FSGS on hematoxylin and eosin-stained slides. The renal tissue samples were also treated with immunostains for WT-1, TGF-β, VEGF, and ET-1. The glomeruli in all the FSGS kidneys showed loss of WT-1 expression with a concomitant notable increased expression of TGF-β, VEGF, and ET-1 immunostains. These results demonstrate that as FSGS evolves, the WT-1-expressing podocytes are lost and it correlates inversely with the overexpression of TGF-β, VEGF, and ET-1, suggesting that during the pathogenesis of FSGS, podocyte damage triggers the activation of these proteins. The findings in the current study echo the theory hypothesized in world literature that TGF-β, VEGF, and ET-1 play an integral part in the evolution of FSGS. More research is needed to further detail the pathogenic role of these proteins as it may open routes to more targeted and effective treatment modalities.

Breast cancer is a heterogenous disease at the molecular level thus, it can be hypothesized that different molecular subtypes differ in their tumor microenvironment (TME) also. Understanding the TME heterogeneity may provide new prognostic biomarkers and new targets for cancer therapy. For deciphering heterogeneity in the TME, immunohistochemistry for immune markers (CD3, CD4, CD8, CD68, CD163, and programmed death-ligand 1), Cancer-associated fibroblast markers [anti-fibroblast activating protein α (FAP-α), platelet-derived growth factor receptor α (PDGFR-α), S100A4, Neuron-glial antigen 2, and Caveolin-1], and angiogenesis (CD31) was performed on tissue microarrays of different molecular subtypes of breast cancer. High CD3 + T cells were noted in the Luminal B subtype ( P =0.002) of which the majority were CD8 + cytotoxic T cells. Programmed death-ligand 1 expression in immune cells was highest in the human epidermal growth factor receptor 2 (Her-2)-positive and Luminal B subtypes compared with the triple-negative breast cancer (TNBC) subtype ( P =0.003). Her-2 subtype is rich in M2 tumor-associated macrophages ( P =0.000) compared with TNBC and Luminal B subtypes. M2 immune microenvironment correlated with high tumor grade and high Ki-67. Her-2 and TNBC subtypes are rich in extracellular matrix remodeling (FAP-α, P =0.003), angiogenesis-promoting (PDGFR-α; P =0.000) and invasion markers (Neuron-glial antigen 2, P =0.000; S100A4, P =0.07) compared with Luminal subtypes. Mean Microvessel density showed an increasing trend: Luminal A>Luminal B>Her-2 positive>TNBC; however, this difference was not statistically significant. The cancer-associated fibroblasts (FAP-α, PDGFR-α, and Neuron-glial antigen 2) showed a positive correlation with lymph node metastasis in specific subtypes. Immune cells, tumor-associated macrophage, and cancer-associated fibroblast-related s tromal markers showed higher expression in Luminal B, Her-2 positive, and TNBC respectively. This differential expression of different components of TME indicates heterogeneity of the TME across molecular subtypes of breast cancer.

PD-L1 IHC 22C3 pharmDx is an FDA-approved companion test to select patients for anti-PD-L1 immunotherapy. In head and neck squamous cell carcinoma PD-L1 expression is determined using a Combined Positive Score (CPS), which evaluates expression in tumor cells and tumor-associated leukocytes. We hypothesized that in nodal metastasis, the CPS should be higher given their inherent higher proportion of leukocytes. A significant difference in CPS between sites would mean that the tissue chosen for PD-L1 testing would impact patient eligibility for therapy. Currently, guidelines about which tissue should be tested do not exist. PD-L1 22C3 IHC was performed in the primary and nodal metastases of 35 head and neck squamous cell carcinoma, and a CPS was generated by 3 pathologists. Mean CPS was higher at the primary than the nodal metastasis: 47.2 versus 42.2; however, the difference was not statistically significant: P=0.259 . By therapeutic groups: negative (CPS <1), low (CPS 1-19) and high (CPS≥20), low-expression was more common in the primary: 40 vs. 26%, and high-expression in the nodal metastasis: 74 vs. 60% but this difference was not statistically significant: P=0.180. Stratified by positive versus negative (CPS <1 vs. ≥1), there were no differences between sites. Interobserver agreement for CPS among the 3 raters was slight for both sites: ƙ = 0.117 and 0.025, fair if stratified by therapeutic group: ƙ = 0.371 and 0.318, and near perfect if stratified as negative versus positive: ƙ = 0.652 and 1. There were no statistically significant differences in CPS between primary and nodal metastases independent of how the CPS was stratified.