Applied Immunohistochemistry & Molecular Morphology最新文献

Background: The WHO classification of central nervous system neoplasms (2016) recognized 4 histologic variants and genetically defined molecular subgroups within medulloblastoma (MB). Further, in the 2021 classification, new subtypes have been provisionally added within the existing subgroups reflecting the biological diversity. YAP1, GAB1, and β-catenin were conventionally accepted as surrogate markers to identify these genetic subgroups.

Objectives: We aimed to stratify MB into molecular subgroups using 3 immunohistochemical markers. TP53 mutation was also assessed in Wingless (WNT), and Sonic Hedgehog (SHH) subgroups. Demographic profiles, imaging details, and survival outcomes were compared within these molecular subgroups.

Patients and methods: Our cohort included 164 MB cases diagnosed over the last 10 years. The histologic variants were identified on histology, and tumors were molecularly stratified using YAP1, GAB1, and β-catenin. Further, TP53 mutation was assessed using immunohistochemical in WNT and SHH subgroups. The clinical details and survival outcomes were retrieved from the records, and the mentioned correlates were evaluated statistically.

Results: The age ranged from 1 to 52 years with M:F ratio of 2:1. Group 3/group 4 constituted the majority (48.4%), followed by SHH (45.9%) and WNT subgroups (5.7%). Desmoplastic/nodular and MB with extensive nodularity had the best survival, whereas large cell/anaplastic had the worst. The follow-up period ranged from 1 to 129 months. The best outcome was observed for the WNT subgroup, followed by the SHH subgroup; group 3/group 4 had the worst. Among the SHH subgroup, TP53 mutant tumors had a significantly poorer outcome compared with SHH-TP53 wildtype.

Conclusions: Molecular stratification significantly contributes to prognostication, and a panel of 3 antibodies is helpful in stratifying MB into its subgroups in centers where access to advanced molecular testing is limited. Our study reinforces the efficacy of incorporating this cost-effective, minimal panel into routine practice for stratification. Further, we propose a 3-risk stratification grouping, incorporating morphology and molecular markers.

The aim of this study was to investigate the expression and clinical significance of MTA2 and CPNE1 proteins in cervical squamous cell carcinoma. In this study, high-risk human papillomavirus (HPV) typing was performed on cervical cancer tissues. Reverse transcription polymerase chain reaction and immunochemical EliVision method were used to examine the expressions of MTA2 and CPNE1 in the cervix, and their relationship with clinicopathologic features. We found that it is mainly distributed in these types, namely HPV-16 (23.8%), HPV-18 (20.9%), HPV-53 (17.1%), HPV-52 (15.5%), HPV-82 (11.7%), HPV-56 (10.8%). The expressions of MTA2 and CPNE1 in cervical squamous cell carcinoma tissues were significantly higher than those in normal tissues ( P <0.01). The expressions of MTA2 and CPNE1 were correlated with FIGO stage, degree of differentiation, and lymph node metastasis of cervical cancer ( P <0.05), but not with the patient's age ( P >0.05). The rank correlation coefficient of MTA2 and CPNE1 protein expression in cervical squamous cell carcinoma was 0.668 ( P <0.01), and the 2 expressions were positively correlated. MTA2 and CPNE1 are closely related to the occurrence and development of cervical squamous cell carcinoma and may play a synergistic role in the evolution of cervical squamous cell carcinoma.

The American Society of Clinical Oncology and the College of American Pathologists (ASCO/CAP) guidelines are used for human epidermal growth factor receptor 2 (HER2) reporting in breast carcinoma. Cases that demonstrate weak to moderate complete membrane immunohistochemical staining in >10% of the tumor are scored as 2+ (equivocal). This study aimed to determine what proportion of HER2 immunohistochemistry (IHC) score = 2+ breast carcinomas were confirmed to be positive by HER2 fluorescent in situ hybridization (FISH). There were 241 HER2 IHC score = 2+ breast carcinomas included. Most (74.3%) carcinomas were estrogen and progesterone receptor-positive. Invasive breast carcinoma of no special type (89.2%) was the commonest histologic subtype. Most tumors were grade 2 (64.3%). As per the FISH report, at the time of diagnosis, 27 cases (11.2%) were HER2 FISH positive. All HER2 FISH equivocal cases and one FISH positive case assessed using the 2013 ASCO/CAP HER2 criteria were reclassified to HER2 FISH negative when the 2018 criteria were applied. There was a high level of agreement (κ = 0.979) between HER2 FISH results obtained using the 2013 and the 2018 criteria. This study provides insight into the frequency of HER2 FISH positivity (11.2%) among HER2 IHC score = 2+ breast carcinomas and the impact of modifications to the ASCO/CAP HER2 guidelines. Elimination of the HER2 FISH equivocal category by the 2018 guidelines has reduced the need for repeat testing and simplified clinical management. Reclassification of previous HER2 FISH positive to negative has resulted in some patients being ineligible for costly anti-HER therapy.

Immunohistochemistry (IHC), also referred to as immunocytochemistry in cytology literature, has revolutionized the practice of cytopathology. Because of the complexity of cytology preparation and limited diagnostic material, performing IHC remains a challenge. Formalin-fixed paraffin-embedded (FFPE) cell block (CB) is the optimal choice for IHC. In this review, the approaches for improving CB preparation will be discussed. When CB material is not available, various cytology specimens can also be used for IHC. With the utilization of Antigen Retrieval (AR) technique, these nonformalin-fixed cytology specimens can achieve successful IHC staining, comparable with the results from FFPE tissue sections. In the last part of this review, we will discuss the use of positive controls and the important role of AR in standardization of IHC in cytology.

Starting in the mid-1970s, we formed a group of pathologists with a major interest in uropathology. Originally, it included 2 (R.M. and M.S.). In the years the followed, the group was enlarged to include 4 more people, 2 in the mid- and late-1980s (A.L.B. and L.C.) and another in the mid-1990s (R.Ma.); a sixth (A.C.) joined the group ∼5 years ago. Two have reached the retirement age (R.M. and M.S.), while others are in the process of joining the group to replace them. A fruitful collaboration spanned for ∼45 years. This contribution is based on a series of personal recollections of the successive changes in the interpretation of prostate cancer and its precursors, starting in the mid-1970s. Here we have retraced our involvement steps, sharing issues related to them with a junior uropathologist (A.C.).

This review is based on a webinar I presented for the International Society for Immunohistochemistry and Molecular Morphology (ISIMM) in February 2022. It is intended that all ISIMM webinars will ultimately be published in AIMM as review articles. This work is also dedicated to Clive Taylor, who has deeply impacted my career. It presents a molecularly informed, pattern-based approach to p53 immunohistochemistry interpretation, methodological considerations (ie, antibody selection, optimization, validation, controls, and external quality assessment), and pan-cancer diagnostic applications, including those drawn from gastrointestinal, genitourinary, gynecological, neuroendocrine, hematologic, and neuropathology. It intends to prove the thesis statement that p53 is an exemplar next-generation immunohistochemical marker "born" ahead of its time.

Magee equations (MEs) are a set of multivariable models that were developed to estimate the actual Onco type DX (ODX) recurrence score in invasive breast cancer. The equations were derived from standard histopathologic factors and semiquantitative immunohistochemical scores of routinely used biomarkers. The 3 equations use slightly different parameters but provide similar results. ME1 uses Nottingham score, tumor size, and semiquantitative results for estrogen receptor (ER), progesterone receptor, HER2, and Ki-67. ME2 is similar to ME1 but does not require Ki-67. ME3 includes only semiquantitative immunohistochemical expression levels for ER, progesterone receptor, HER2, and Ki-67. Several studies have validated the clinical usefulness of MEs in routine clinical practice. The new cut-off for ODX recurrence score, as reported in the Trial Assigning IndividuaLized Options for Treatment trial, necessitated the development of Magee Decision Algorithm (MDA). MEs, along with mitotic activity score can now be used algorithmically to safely forgo ODX testing. MDA can be used to triage cases for molecular testing and has the potential to save an estimated $300,000 per 100 clinical requests. Another potential use of MEs is in the neoadjuvant setting to appropriately select patients for chemotherapy. Both single and multi-institutional studies have shown that the rate of pathologic complete response (pCR) to neoadjuvant chemotherapy in ER+/HER2-negative patients can be predicted by ME3 scores. The estimated pCR rates are 0%, <5%, 14%, and 35 to 40% for ME3 score <18, 18 to 25, >25 to <31, and 31 or higher, respectively. This information is similar to or better than currently available molecular tests. MEs and MDA provide valuable information in a time-efficient manner and are available free of cost for anyone to use. The latter is certainly important for institutions in resource-poor settings but is also valuable for large institutions and integrated health systems.

Immunohistochemistry (IHC) is a testing methodology that is widely used for large number of diagnostic, prognostic, and predictive biomarkers. Although IHC is a qualitative methodology, in addition to threshold-based stratification (positive vs. negative), the increasing levels of expression of some of these biomarkers often lead to more intense staining, which published evidence linked to specific diagnosis, prognosis, and responses to therapy. It is essential that the descriptive thresholds between positive and negative staining, as well as between frequently used graded categories of staining intensity (eg, 1+, 2+, 3+) are standardized and reproducible. Histo-score (H-score) is a frequently used scoring system that utilizes these categories. Our study introduces categorization of the cutoff points between positive and negative results and graded categories of staining intensity for nuclear IHC biomarker assays based on color interaction between hematoxylin and diaminobenzidine (DAB); the Blue-brown Color H-score (BBC-HS). Six cases of diffuse large B-cell lymphoma were stained for a nuclear marker MUM1. The staining was assessed by H-score by 12 readers. Short tutorial and illustrated instructions were provided to readers. The novel scoring system in this study uses the interaction between DAB (DAB, brown stain) and hematoxylin (blue counterstain) to set thresholds between "0" (negative nuclei), "1+" (weakly positive nuclei), "2+" (moderately positive nuclei), and "3+" (strongly positive nuclei). The readers recorded scores for 300 cells. Krippendorff alpha (K-alpha) and intraclass correlation coefficient (ICC) were calculated. We have also assessed if reliability improved when counting the first 100 cells, first 200 cells, and for the total 300 cells using K-alpha and ICC. To assess the performance of each individual reader, the mean H-score and percent positive score (PPS) for each case was calculated, and the bias was calculated between each reader's score and the mean. K-alpha was 0.86 for H-score and 0.76 for PPS. ICC was 0.96 for H-score and 0.92 for PPS. The biases for H-score ranged from -58 to 41, whereas for PPS it ranged from -27% to 33%. Overall, most readers showed very low bias. Two readers were consistently underscoring and 2 were consistently overscoring compared with the mean. For nuclear IHC biomarker assays, our newly proposed cutoffs provide highly reliable/reproducible results between readers for positive and negative results and graded categories of staining intensity using existing morphologic parameters. BBC-HS is easy to teach and is applicable to both human eye and image analysis. BBC-HS application should facilitate the development of new reliable/reproducible scoring schemes for IHC biomarkers.