Quantitative measurement of HER2 expression to subclassify ERBB2 unamplified breast cancer.

The efficacy of the antibody drug conjugate (ADC) Trastuzumab deruxtecan (T-DXd) in HER2 low breast cancer patients suggests that the historical/conventional assays for HER2 may need revision for optimal patient care. Specifically, the conventional assay is designed to distinguish amplified HER2 from unamplified cases but is not sensitive enough to stratify the lower ranges of HER2 expression. Here we determine the optimal dynamic range for unamplified HER2 detection in breast cancer and then redesign an assay to increase the resolution of the assay to stratify HER2 expression in unamplified cases.

Preanalytics and Precision Pathology: Pathology Practices to Ensure Molecular Integrity of Cancer Patient Biospecimens for Precision Medicine.

Biospecimens acquired during routine medical practice are the primary sources of molecular information about patients and their diseases that underlies precision medicine and translational research. In cancer care, molecular analysis of biospecimens is especially common because it often determines treatment choices and may be used to monitor therapy in real time. However, patient specimens are collected, handled, and processed according to routine clinical procedures during which they are subjected to factors that may alter their molecular quality and composition.

Programmed Death-Ligand 1 Immunohistochemistry Testing: A Review of Analytical Assays and Clinical Implementation in Non-Small-Cell Lung Cancer.

Purpose Three programmed death-1/programmed death-ligand 1 (PD-L1) inhibitors are currently approved for treatment of non-small-cell lung cancer (NSCLC). Treatment with pembrolizumab in NSCLC requires PD-L1 immunohistochemistry (IHC) testing. Nivolumab and atezolizumab are approved without PD-L1 testing, though US Food and Drug Administration-cleared complementary PD-L1 tests are available for both.

The blood DNA virome in 8,000 humans.

The characterization of the blood virome is important for the safety of blood-derived transfusion products, and for the identification of emerging pathogens. We explored non-human sequence data from whole-genome sequencing of blood from 8,240 individuals, none of whom were ascertained for any infectious disease. Viral sequences were extracted from the pool of sequence reads that did not map to the human reference genome.

Validation of an electronic program for pathologist training in the interpretation of a complex companion diagnostic immunohistochemical assay.

Companion diagnostics assay interpretation can select patients with the greatest targeted therapy benefits. We present the results from a prospective study demonstrating that pathologists can effectively learn immunohistochemical assay-interpretation skills from digital image-based electronic training (e-training). In this study, e-training was used to train board-certified pathologists to evaluate non-small cell lung carcinoma for eligibility for treatment with onartuzumab, a MET-inhibiting agent.

The Cancer Genomics Resource List 2014.

Context: Genomic sequencing for cancer is offered by commercial for-profit laboratories, independent laboratory networks, and laboratories in academic medical centers and integrated health networks. The variability among the tests has created a complex, confusing environment.

Objective: To address the complexity, the Personalized Health Care (PHC) Committee of the College of American Pathologists proposed the development of a cancer genomics resource list (CGRL).

Assessing the discordance rate between local and central HER2 testing in women with locally determined HER2-negative breast cancer.

Background: The importance of human epidermal growth factor receptor 2 (HER2) as a prognostic and predictive marker in invasive breast cancer is well established. Accurate assessment of HER2 status is essential to determine optimal treatment options.

Methods: Breast cancer tumor tissue samples from the VIRGO observational cohort tissue substudy that were locally HER2-negative were retested centrally with both US Food and Drug Administration (FDA)-approved immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) assays, using FDA-approved assay cutoffs; results were compared.

Analytic performance studies and clinical reproducibility of a real-time PCR assay for the detection of epidermal growth factor receptor gene mutations in formalin-fixed paraffin-embedded tissue specimens of non-small cell lung cancer.

Background: Epidermal growth factor receptor (EGFR) gene mutations identify patients with non-small cell lung cancer (NSCLC) who have a high likelihood of benefiting from treatment with anti-EGFR tyrosine kinase inhibitors. Sanger sequencing is widely used for mutation detection but can be technically challenging, resulting in longer turn-around-time, with limited sensitivity for low levels of mutations. This manuscript details the technical performance verification studies and external clinical reproducibility studies of the cobas EGFR Mutation Test, a rapid multiplex real-time PCR assay designed to detect 41 mutations in exons 18, 19, 20 and 21.

Mammostrat as an immunohistochemical multigene assay for prediction of early relapse risk in the tamoxifen versus exemestane adjuvant multicenter trial pathology study.

Purpose: Some postmenopausal patients with hormone-sensitive early breast cancer remain at high risk of relapse despite endocrine therapy and, in addition, might benefit from adjuvant chemotherapy. The challenge is to prospectively identify such patients. The Mammostrat test uses five immunohistochemical markers to stratify patients regarding recurrence risk and may inform treatment decisions.

Multisite analytic performance studies of a real-time polymerase chain reaction assay for the detection of BRAF V600E mutations in formalin-fixed, paraffin-embedded tissue specimens of malignant melanoma.

Context: A polymerase chain reaction-based companion diagnostic (cobas 4800 BRAF V600 Mutation Test) was recently approved by the US Food and Drug Administration to select patients with BRAF-mutant metastatic melanoma for treatment with the BRAF inhibitor vemurafenib.

Objectives: (1) To compare the analytic performance of the cobas test to Sanger sequencing by using screening specimens from phase II and phase III trials of vemurafenib, and (2) to assess the reproducibility of the cobas test at different testing sites.

Design: Specimens from 477 patients were used to determine positive and negative percent agreements between the cobas test and Sanger sequencing for detecting V600E (1799T>A) mutations.

Sensitive multiplex detection of KRAS codons 12 and 13 mutations in paraffin-embedded tissue specimens.

Background: Colorectal cancer patients harbouring KRAS mutations in codon 12 or 13 do not benefit from current anti-epidermal growth factor receptor (EGFR) monoclonal antibody therapies. Efficient and robust methods are therefore required for routine clinical testing of KRAS mutation status.

Aims: To evaluate a novel multiplex assay for the rapid detection of common KRAS mutations in formalin-fixed paraffin-embedded (FFPE) tissues.

Fixation time does not affect the expression of estrogen receptor.

The purpose of this pilot study was to determine the impact of the length of fixation in 10% buffered formalin on the expression of estrogen receptor by immunohistochemical analysis. We studied tissue samples from 10 invasive breast cancer cases after fixation for 1, 3, 6, and 9 to 10 hours. The tissue was processed immediately after fixation, resembling routine practice.

The role of KRAS mutation testing in the management of patients with metastatic colorectal cancer.

Context: KRAS mutations can be detected in approximately 30% to 40% of all patients with colorectal cancer. Several recent studies have shown that patients with KRAS mutations in codons 12 or 13 in metastatic tumors do not benefit from anti-epidermal growth factor receptor therapy with cetuximab or panitumumab.

Objective: To review the literature on the role of KRAS mutation testing for management of patients with metastatic colorectal cancer and to discuss testing strategies.

Genetic heterogeneity in HER2 testing in breast cancer: panel summary and guidelines.

Context: Intratumoral heterogeneity of HER2 gene amplification has been well documented and represents subclonal diversity within the tumor. The reported incidence of intratumor HER2 amplification genetic heterogeneity ranges in the literature from approximately 5% to 30%. The presence of HER2 genetic heterogeneity may increase subjectivity in HER2 interpretation by the pathologist.

HER-2/neu testing in breast cancer.

The testing of newly diagnosed breast cancer specimens for HER-2/neu status has achieved "standard of practice" status for the management of breast cancer in the United States. The discussion as to the best method to determine HER-2/neu status in these samples continues, with the fluorescence in situ hybridization method gaining popularity owing to the recent evidence that it, in comparison with immunohistochemical analysis, might more accurately predict clinical responses to trastuzumab-based therapies. With trastuzumab achieving excellent results in the treatment of HER-2/neu-positive advanced disease and under extensive evaluation in major clinical trials for its potential efficacy when used at earlier clinical stages, the potential role(s) for HER-2/neu testing as a predictor of response to other therapies being resolved by large prospective clinical outcome studies, and the more convenient gene-based chromogenic in situ hybridization technique "waiting in the wings," the saga of HER-2/neu testing in breast cancer will continue to unfold over the next several years.

Enhanced accuracy and reliability of HER-2/neu immunohistochemical scoring using digital microscopy.

We evaluated the HER-2/neu status of 129 invasive breast cancer specimens for gene amplification by fluorescence in situ hybridization (FISH) and protein overexpression by immunohistochemical analysis. Each immunohistochemically stained slide was interpreted on a standard microscope independently by 10 pathologists. Separately, each pathologist reviewed the same slide set with the assistance of digital microscopy.

Laser therapy of breast cancer with 3-year follow-up.

Breast cancer is the commonest female malignancy in the United States and is increasingly being detected at a non-palpable stage by annual mammography. Minimally invasive methods of its local treatment have been recently introduced as alternative to its surgical removal. The case reported in this article illustrates the advantages of in-situ ablation with minimal discomfort to the patient and deformity of the breast.

HER-2/neu protein overexpression and gene amplification in human transitional cell carcinoma of the bladder.

Objectives: To assess HER-2/neu gene status by fluorescence in situ hybridization and protein expression by immunohistochemistry in human bladder transitional cell carcinoma (TCC). In breast carcinoma, HER-2/neu gene amplification and receptor protein overexpression are tightly correlated and have prognostic and therapeutic implications.

Methods: We used 54 randomly selected TCC specimens obtained from 1998 to 2000.

Targeted therapy in breast cancer: the HER-2/neu gene and protein.

The HER-2/neu oncogene, a member of the epidermal growth factor receptor or erb gene family, encodes a transmembrane tyrosine kinase receptor that has been linked to prognosis and response to therapy with the anti-HER-2-humanized monoclonal antibody, trastuzumab (Herceptin, Genentech, South San Francisco, CA) in patients with advanced metastatic breast cancer. HER-2/neu status has also been tested for its ability to predict the response of breast cancer to other therapies including hormonal therapies, topoisomerase inhibitors, and anthracyclines. This review includes an analysis of 80 published studies encompassing more than 25,000 patients designed to consider the relative advantages and disadvantages of the various methods of measuring HER-2/neu in clinical breast cancer specimens.

Radiofrequency ablation of invasive breast carcinoma followed by delayed surgical excision.

Background: Radiofrequency ablation (RFA) is gaining acceptance as a treatment modality for several tumor types. However, its use in patients with breast carcinoma remains investigational. The current study was undertaken to determine the feasibility of treating small breast malignancies with RFA and to evaluate the postablation magnetic resonance imaging scans (MRI) and histologic findings.

The Her-2/neu gene and protein in breast cancer 2003: biomarker and target of therapy.

The HER-2/neu oncogene encodes a transmembrane tyrosine kinase receptor with extensive homology to the epidermal growth factor receptor. In this review, the association of HER-2/neu gene and protein abnormalities with prognosis and response to therapy with trastuzumab and to other therapies in breast cancer is presented. By considering a series of 80 published studies encompassing more than 25,000 patients, the relative advantages and disadvantages of Southern blotting, polymerase chain reaction amplification, and fluorescence in situ hybridization assays designed to detect HER-2/neu gene amplification are compared with HER-2/neu protein overexpression assays performed by immunohistochemical techniques applied to frozen and paraffin-embedded tissues and enzyme immunoassays performed on tumor cytosols.

Assessment of Her-2/Neu status by immunohistochemistry and fluorescence in situ hybridization in mammary Paget disease and underlying carcinoma.

HER-2/Neu overexpression is seen in 20% to 30% of invasive breast carcinomas and has been reported in as many as 80% of high-grade infiltrating carcinomas. Earlier studies have suggested that 100% of the tumor cells in mammary Paget disease show overexpression of HER-2 protein. We undertook this study to assess HER-2 status of mammary Paget disease and of the underlying breast carcinoma, when present, by immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH).

Glycoprotein A-80 in the human prostate: immunolocalization in prostatic intraepithelial neoplasia, carcinoma, radiation failure, and after neoadjuvant hormonal therapy.

Objectives: To review the expression of A-80 in prostate cancer and prostatic intraepithelial neoplasia and compare it with that of normal and hyperplastic prostatic tissue. The ability to recognize cancer after androgen deprivation therapy and residual and/or recurrent cancer after radiotherapy using A-80 staining was also examined. A-80 is a glycoprotein linked to exocrine differentiation that shows little or no expression in normal exocrine cells, but is selectively overexpressed in dysplasias and adenocarcinomas.