Ethical Considerations in Multiple Pregnancy: Preterm Delivery in the Setting of Discordant Fetal Anomaly.

Planning for the preterm birth of a fetus with known anomalies can raise complex ethical issues. This is particularly true of multiple pregnancies, where the interests of each fetus and of the expectant parent(s) can conflict. In these complex situations, parental wishes and values can also conflict with the recommendations of treating clinicians. In this article, we consider the case of a dichorionic twin pregnancy complicated by the diagnosis of vein of Galen aneurysmal malformation (VGAM) in one of the twins at 28 weeks' gestation. Subsequent deterioration of the affected twin prompted the parents to request preterm delivery to prevent the imminent in-utero demise of the affected twin. However, given the associated risks of prematurity, complying with the parents' request may have disadvantaged the health and wellbeing of the unaffected twin. This article canvases the complex ethical issues raised when parents request preterm delivery of a multiple pregnancy complicated by a fetal anomaly in one twin, and the various ethical tools and frameworks that clinicians can draw on to guide their decision-making in such cases.

Development of a Diagnostic Programmed Cell Death 1-Ligand 1 Immunohistochemistry Assay for Nivolumab Therapy in Melanoma.

Nivolumab is a monoclonal antibody that blocks the interaction between programmed cell death 1 (PD1) and programmed cell death 1-ligand 1 (PD-L1), resulting in enhanced antitumor activity by the immune system. Nivolumab is currently approved by the US Food and Drug Administration (FDA) for melanoma, non-small cell lung cancer (NSCLC), renal cell carcinoma, classical Hodgkin lymphoma, squamous cell carcinoma of the head and neck, and urothelial carcinoma. PD-L1 IHC 28-8 pharmDx is FDA-approved as a complementary diagnostic for immunohistochemical (IHC) detection of PD-L1 in non-squamous NSCLC and melanoma. We report validation of PD-L1 IHC 28-8 pharmDx for PD-L1 detection on formalin-fixed, paraffin-embedded human melanoma specimens using Autostainer Link 48. A prevalence assessment of 104 melanoma specimens indicated that PD-L1 was detected across the full expression level range (0% to 100% of tumor cells). Assay robustness and precision studies were conducted at Agilent Technologies, with additional reproducibility studies performed at 3 external laboratories. Precision studies evaluated at ≥1% and ≥5% expression levels revealed a range of average negative agreement from 89.5%, 95% CI (83.2, 93.6) to 100%, 95% CI (97.3, 100), and average positive agreement from 85.5%, 95% CI (77.6, 90.9) to 100%, 95% CI (97.9, 100). For external reproducibility, precise results were obtained. These results demonstrate PD-L1 IHC 28-8 pharmDx is a precise, robust, and reproducible assay for determining PD-L1 expression in melanoma. This is the first PD-L1 IHC test to receive FDA approval as a complementary diagnostic in melanoma patients whereby positive PD-L1 expression is correlated with the magnitude of nivolumab treatment effect.

Development of standard estrogen and progesterone receptor immunohistochemical assays for selection of patients for antihormonal therapy.

Estrogen receptor (ER) and progesterone receptor (PR) status in breast carcinomas are considered validated predictive factors for selecting patients for antihormonal therapy. Published surveys have shown a significant rate of disagreement and lack of reproducibility of immunohistochemistry (IHC) results from laboratories around the world. To address these limitations IHC assays for ER and PR were developed using characterized reagents, after careful calibration of the sensitivity and specificity to match established assays previously validated in large clinical studies. The ER assay uses a cocktail of 2 mouse monoclonal antibodies (1D5 and ER-2-123) and the PR assay uses 1 mouse monoclonal antibody (PgR 1294); both are followed by a polymer-peroxidase-based detection system. All antibodies were tested for specificity by epitope mapping. The sensitivity of the new assays was calibrated to be equivalent to previously validated IHC assays followed by a comparison with the validated assays in a concordance study involving over 200 specimens. All slides were scored with the "Allred Score," also used for scoring of the original validated assays. The overall concordance between the new and the established IHC assays was nearly perfect (99%). The concordance study demonstrated greater than 98% positive agreement and 100% negative agreement of the new IHC assays with the previously validated IHC assays. This equivalence establishes the clinical validation of the assays and, as they are based on newer generation reagents and are produced and tested under stringent quality control conditions to ensure their consistency, they add additional advantages to the user and patients.

Development of an automated PD-L1 immunohistochemistry (IHC) assay for non-small cell lung cancer.

Nivolumab, a fully human IgG4 programmed death 1 (PD-1) immune checkpoint inhibitor antibody, developed by Bristol-Myers Squibb Inc., has activity across non-small cell lung cancer (NSCLC) histologies and is Food and Drug Administration approved for treatment of metastatic squamous NSCLC with progression on or after platinum-based chemotherapy. PD-L1 has been investigated as a potential biomarker to predict clinical response to nivolumab in clinical settings. We report an automated PD-L1 immunohistochemistry (IHC) assay, which was developed to detect cell surface PD-L1 in formalin-fixed paraffin-embedded human tumor tissue specimens using Dako's Autostainer Link 48. The primary antibody for this assay is a rabbit monoclonal anti-human PD-L1 antibody, clone 28-8. The specificity of 28-8 for PD-L1 was demonstrated by antigen competition and genetic deletion of PD-L1 in tumor cell lines. The specificity of the PD-L1 IHC assay was further evaluated in a collection of 30 normal human tissues. The PD-L1 IHC assay was optimized for high sensitivity and precision in routine application. A pathology scoring and interpretation method specific to nivolumab clinical studies was adopted for the assay. The analytical performance of the assay was validated for application in the determination of PD-L1 status in human NSCLC specimens. The clinical application of the assay and scoring method was further validated in 3 Clinical Laboratory Improvement Amendments certified labs. The assay is currently being investigated in a variety of clinical studies for use as an in vitro diagnostic to select and stratify patients for treatment with the anti-PD-1 therapeutic antibody, nivolumab.

EP1: a novel rabbit monoclonal antibody for detection of oestrogen receptor α.

AIMS: Assessment of hormone receptor expression is part of routine examination of every breast cancer. In this study, we report the characterisation of a novel rabbit monoclonal antibody, clone EP1, directed against oestrogen receptor (ER) α. Additionally, its immunohistochemical performance characteristics in archival tissues are evaluated in normal tissues and two distinct cohorts of breast cancer patients. METHODS: Comparative analyses between EP1 and the anti-ERα component of the ER/PR pharmDx kit (cocktail of mouse monoclonal antibody clones 1D5 and ER-2-123) and between EP1 and another commercially available rabbit monoclonal antibody, clone SP1, are described. RESULTS: Clone EP1 specifically detects nuclear ER in all tissues examined; cytoplasmic staining was not observed. The analysis shows a high degree of concordance (~95%) between EP1 and both the ERα component of the Dako ER/PR pharmDx kit and Ventana clone SP1. However, the use of EP1 antibody together with Dako EnVision FLEX detection system resulted in a stronger staining intensity as compared with SP1 antibody using the Ventana ultraView DAB detection system resulting in better 'ease of use.' CONCLUSIONS: The use of EPI can result in better interpretation of the results of the ER analysis.