Applied Immunohistochemistry & Molecular Morphology最新文献

For patients with metastatic triple-negative breast cancer (TNBC), treatment with pembrolizumab is dependent on the accurate determination of programmed death ligand 1 (PD-L1) expression using immunohistochemistry (IHC). This study evaluated the interobserver concordance in assessing PD-L1 expression on TNBC samples using the commercial 22C3 IHC assay and an in-house assay based on the E1L3N antibody. Concordance between the 22C3 and the E1L3N IHC assays was evaluated on TNBC samples read by a commercial laboratory and a Brigham and Women's Hospital breast pathologist (BWH reader). Each slide was given a PD-L1 combined positive score (CPS) and was considered PD-L1 positive or negative based on the CPS cutoff of 10. Interobserver concordance for the assays was also evaluated on a subset of samples between 2 and 3 independent readers. On 71 samples, 2 independent readers (1 BWH reader and commercial laboratory) using E1L3N and 22C3, respectively, reached agreement on PD-L1 status (positive/negative) on 64 samples (90.1%). Using 22C3, 2 independent readers reached agreement on PD-L1 status on 30 of 36 samples (83.3%), and 3 independent readers reached agreement on 16 of 27 samples (59.3%). Using E1L3N, 2 BWH readers reached agreement on PD-L1 status on 18 of 27 samples (66.7%). Three BWH readers reached an agreement on 2 of 12 of the most challenging samples (16.7%). In conclusion, concordance between E1L3N and 22C3 testing using CPS for PD-L1 in metastatic TNBC was >90%. However, certain cases were challenging to agree upon using current threshold criteria, highlighting the need for more standardized evidence-based methods to assess PD-L1 expression.

Background: Basaloid skin tumors include subtypes of basal cell carcinoma (BCC) and the basaloid variant of squamous cell carcinoma (SCC). Due to their similarity in pathology and clinical presentation, their diagnosis is not straightforward. The aim of this study was to analyze the immunohistochemical expression of HSP105 in basaloid skin tumors, which include BCC, basosquamous carcinoma (BSC), metatypical basal cell carcinoma (MBCC), basaloid squamous cell carcinoma (BSCC), BCC with squamous differentiation as well as conventional SCC.

Methods: This retrospective study included 17 cases of BCC, 11 cases of BSC, 8 instances of MBCC, 10 cases of BCC with squamous differentiation, 8 cases of BSCC, and 19 cases of SCC. Their clinical characteristics were summarized, and the paraffin blocks of tumor biopsy specimens were collected for HSP105 immunostaining.

Results: In contrast to the BCC group, which stained predominantly negative, SCC stained diffusely positive for HSP105. BSCs showed some areas of HSP105 positivity with a transitional expression signature. HSP105 was only weakly positive in a few cases of MBCC. Although BSCC was stained positive for HSP105, the HSCORE was significantly lower than that of the classic SCC. In BCC with squamous differentiation, focal staining for HSP105 was only seen in the area of squamous differentiation.

Conclusion: There was a difference in immunohistochemical staining of HSP105 in basaloid skin tumors which helps in differential diagnosis. Differentiation between BCC, SCC, BSCC, MBCC, and BCC with squamous differentiation can be aided by immunohistochemistry using HSP105.

Cervical cancer remains one of the leading causes of death from malignant diseases in women worldwide. Primary and secondary prevention have led to better outcomes in developed countries, whereas in developing countries, cervical cancer continues to be responsible for an unjustifiably high number of fatalities. The discovery of new tumor biomarkers can lead to earlier diagnosis, better therapeutic decisions, and improved treatment methods. IMP3 is a protein responsible for invasiveness and other aggressive characteristics of tumor processes. Its highly specific expression has been proven in various malignant processes. The level of IMP3 expression in cervical cancer cells could be used as a prognostic factor for a worse disease course. In this study, IMP3 expression was examined in 80 patients who underwent surgery for squamous cell cervical cancer in the first FIGO stage of the disease, and its association with disease-free period and overall survival was investigated. Data analysis did not show a statistically significant association between IMP3 expression and the mentioned primary outcomes, despite its association with clinical-pathological indicators of advanced disease. In conclusion, the analysis of IMP3 protein expression in patients with early-stage cervical cancer is of limited utility.

Bovine pericardium (BP) is widely used as a biomaterial for tissue engineering. Glutaraldehyde and formaldehyde are commonly employed in the reticulation processes to enhance the material's resistance and preservation. In this study, we assessed the impact of long-term storage in 4% formaldehyde on the quantitative expression of immunophenotypic markers in glutaraldehyde-treated BP. Histologic and immunohistochemical analyses were performed on 2 BP patches, manufactured in 2009 and 2020, respectively. Braile Biomédica provided the BP patches. Sections of BP were stained with H&E, Weigert, and picrosirius red, followed by immunolabeling for vimentin, laminin 5, collagen I, and collagen IV using a standardized protocol. Microscopic images were captured using light and polarized microscopy, and the area of the antibody signal was quantified using Image J Software. Histologic analysis showed no autolysis or significant changes in the patches. Immunohistochemical analysis revealed a diffuse distribution of collagen I and collagen IV throughout the connective tissue of the patches. The 2020 specimen exhibited higher expression levels of collagen I (21.36%) and collagen IV (24.67%) compared with the 2009 specimen (collagen I: 15.87%; collagen IV: 12.02%). Laminin did not show reactivity in either specimen. Notably, vimentin immunopositivity differed significantly between the patches, with a larger area of expression observed in the 2020 patch (54%) compared with the 2009 patch (13%). In summary, there were no substantial differences in immunophenotypic expression between the 2009 and 2020 BP patches, except for the higher vimentin expression in the 2020 BP patch.

Extranodal marginal zone lymphoma (EMZL) is the most common subtype of ocular lymphomas. Diffuse large B-cell lymphoma (DLBCL) and EMZL with large-cell transformation present diagnostic challenges. Radiotherapy is the standard treatment for ocular lymphomas, but complications and relapse are common. Diagnostic utility in challenging cases, as well as treatment options using immune checkpoint inhibitors, are unclear in ocular lymphomas. We herein investigated the PD-1, PD-L1, and IDO1 staining patterns in 20 cases of ocular lymphomas, including EMZL (n=14), EMZL with increased large cells (n=2), and DLBCL (n=4). PD-1, PD-L1, and IDO1 staining was not detected in lymphoma cells in any cases but was observed within the tumor microenvironment in all cases. Positivity for PD-1, PD-L1, and IDO1 in inflammatory cells was seen either intratumorally or peritumorally. In all 6 cases with significantly more large B cells, the density of PD-1, PD-L1, and IDO1 expression in the tumor microenvironment was higher than that of the remaining 14 cases without large B cells ( P -value<0.0001), whereas other clinicopathologic features showed no statistical correlation. Increased expression of PD-1, PD-L1, and IDO1 in the inflammatory milieu in cases with large cells may provide diagnostic utility in small biopsies as well as therapeutic potential.

Merkel cell carcinoma (MCC) is a rare, highly aggressive skin cancer of neuroendocrine origin that is typically associated with either the presence of Merkel cell polyomavirus or chronic exposure to ultraviolet (UV) light. We report a case of relapsed MCC that presented with new symptoms of fatigue, back pain, and myeloid left shift identified during scheduled follow-up. The patient was found to have circulating neoplastic cells in the peripheral blood and bone marrow metastasis. Immunohistochemistry for synaptophysin, CD56, INSM-1, CK20, CD117 were positive, whereas CD34, TdT, Chromogranin, CD10, myeloperoxidase, CD3 and CD19 were negative. Flow cytometry of the peripheral blood confirmed the presence of an abnormal nonhematopoietic cell population expressing CD56 positivity. A next-generation sequencing (NGS) panel revealed the presence of variants in RB1, TP53, and other genes, some of which have not been previously described in MCC. This rare presentation highlights the challenges in the diagnosis and management of MCC.

Objectives: Colorectal adenocarcinoma and squamous cell carcinoma (SCC) can arise in the anorectum and present a significant diagnostic challenge when poorly differentiated. Accurate diagnosis can significantly influence management, as the treatments for these conditions involve distinct neoadjuvant chemoradiotherapy regimens. MOC-31 and SATB2 have been utilized as specific markers of glandular differentiation and colorectal origin, respectively, but studies have shown that they may be positive in squamous cell carcinoma of other sites. This raises the concern that MOC-31 and SATB2 may be positive in squamous cell carcinoma of the anorectum, and overreliance on these stains may be a potential diagnostic pitfall in differentiating rectal poorly differentiated adenocarcinoma (PDA) from anal nonkeratinizing SCC.

Methods: We identified biopsies from 10 rectal PDA and 17 anorectal nonkeratinizing SCC cases and stained them for MOC-31 and SATB2.

Results: We found that MOC-31 was highly sensitive, being positive in 10/10 cases of rectal PDA, but not specific, as it was also positive in 11/17 SCC cases. In contrast, SATB2 was both sensitive, with positive staining in 10/10 rectal PDA cases, and specific, with negative staining in 17/17 SCC cases. This includes equivocal staining in 4 of these negative SCC cases. MOC-31 had a sensitivity of 100% and specificity of 35.3%, while SATB2 had a sensitivity of 100% and specificity of 100%.

Conclusions: Unlike squamous mucosa of the head and neck, and esophagus, SCC of the anus does not frequently stain positively for SATB2. These data suggest that SATB2 is a reliable marker in distinguishing rectal PDA from anorectal nonkeratinizing SCC, whereas MOC-31 is commonly positive in SCC of the anus. It is also important to note that equivocal SATB2 staining may be seen in SCC.

DDX41 -associated cytopenia(s)/myeloid neoplasms ( DDX41 -C/MNs) are an emerging pathologic entity. We examined the hematopathologic findings in DDX41 -C/MNs with both a germline and somatic DDX41 mutation ( DDX41 -C/MNs-GS). We reviewed the peripheral blood and bone marrow (BM) findings from treatment-naive patients with DDX41 -C/MNs-GS. Thirty cases were identified: 10% (3/30) were classified as clonal cytopenia(s) of unknown significance (CCUS), 17% (5/30) as myelodysplastic neoplasm/syndrome (MDS) with <5% blasts, 20% (6/30) as MDS with 5% to 9% blasts, 20% (6/30) as MDS with 10% to 19% blasts, and 33% (10/30) as acute myeloid leukemia (AML). All patients were cytopenic; circulating blasts were rare (23%, 7/30). 63% (19/30) showed dysmegakaryopoiesis. Dyserythropoiesis and dysgranulopoiesis were uncommon; seen in 20% (6/30) and 7% (2/30), respectively. Sixty-six percent (19/29) of cases were normocellular; 43% (13/30) showed erythroid predominance. Flow cytometry revealed an unremarkable blast myeloid phenotype. Blasts were intermediate sized with round nuclei, distinct nucleoli, and light blue cytoplasm with azurophilic granules. The karyotype was predominantly normal (93%, 26/28). All germline mutations were deleterious: 53% (16/30) truncating and 47% (14/30) missense. The most common somatic variant was the R525H mutation in 70% (21/30). The BM diagnostic spectrum in DDX41- C/MNs that harbor both a germline and somatic DDX41 mutation is broad-ranging from CCUS to AML. We describe consistent hematopathologic findings that pathologists may expect in these cases.

SATB2 has been reported to be highly specific for lower gastrointestinal tract tumors. On the basis of its ileum-colon conversion effects, which involve the activation of colonic genes in cooperation with CDX2 and HNF4A, we hypothesized that SATB2 and CDX2 might define the characteristics of colorectal cancers (CRCs). In the present study, the clinicopathologic and immunohistochemical characteristics of 269 CRCs were analyzed according to SATB2 and CDX2 expression. CRCs with SATB2- and/or CDX2- phenotypes showed associations with poorly differentiated histotypes ( P <0.00001), mucus production ( P =0.0019), and mismatch repair-deficient phenotypes ( P <0.00001). SATB2-/CDX2- CRCs were significantly associated with CK20-negativity, with or without CK7 expression ( P <0.00001), as well as with MUC5AC-positivity ( P <0.00001), and CD10-negativity ( P =0.00047). Negativity for SATB2 or CDX2 was associated with the expression of PD-L1 in both all CRC ( P <0.00001) and mismatch repair-proficient CRC ( P =0.000091). Multivariate Cox hazard regression analysis identified negativity for SATB2 and/or CDX2 as potential independent risk factors for patients with CRC. Regarding the diagnostic utility of SATB2, all of the 44 CRC metastases could be diagnosed as colorectal in origin if the immunohistochemical phenotypes (including CK7, CK20, and p53) of the primary lesions and patient history were considered. Among the other 684 tumors, we were unable to distinguish a case of CK7-/CK20+/CDX2+/SATB2+ ovarian mucinous cystadenocarcinoma from metastatic CRC without the patient history and clinical information.

Targeting the PD1/PD-L1 immune checkpoint pathway has rapidly become a therapeutic strategy for melanoma patients. Indeed, the quantification of PD-L1 expression by immunohistochemistry (IHC) in melanoma samples is already required, in some contexts, to allow access to anti-PD-1/PD-L1 immunotherapy. Despite a rising demand for PD-L1 testing, paralleling increasing cumulative experience in its assessment and quantification, it is fair to recognize that PD-L1 evaluation in melanoma samples still presents some critical issues. The aim of this technical report is to develop and validate a multiplex double staining protocol for PD-L1/SOX10 in Ventana Benchmark Ultra for routine practice. Our results show that double labeling provides the necessary tools to identify PD-L1 + melanoma cells clearly. The simultaneous visualization of 2 different proteins targets allows the topographical relationship between the 2 labeling to be evaluated within the context of the tissue morphology. Future studies are needed to test this technique's real-world applicability and effectiveness in implementing interpathologist agreement.