HER-2 amplification

© 2026 The Author(s). The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland

Stratified analysis revealed that unequivocal cases (Groups 1 + 5, approximately 84% of the cohort) maintained excellent concordance (coefficient of variation <5%) at all tiers, while equivocal cases (Groups 2-4) exhibited persistently higher variability regardless of cell count. These findings validate the 20-cell minimum for routine FISH-based HER2 assessment and demonstrate that enhanced concordance in borderline cases requires adjudicatory workflows beyond additional cell counting.

P1/2, N=129, Not yet recruiting, Medica Scientia Innovation Research S.L.

We present a case of a 66-year-old female with de novo metastatic NSCLC harboring an EGFR mutation, RET rearrangement, and ERBB2 amplification, who experienced transformation to SCLC while on osimertinib. Subsequently, she exhibited primary refractory disease to both first-line platinum doublet with immunotherapy and second-line lurbinectedin...The patient had minimal side effects and obtained a partial response with a progression-free survival (PFS) of 13.1 months, better than historically poor prognosis seen in transformed SCLC. This case underscores the potential role of human epidermal growth factor receptor 2 (HER-2) directed therapies, such as T-DXd, in transformed SCLC.

In summary, our study establishes the comprehensive molecular atlas and a targeted therapeutic subtyping framework, revealing therapeutic vulnerabilities and providing novel insights for advancing precision oncology in OCCC management.

Integrated genomic and transcriptomic profiling refines prognostic stratification in cholangiocarcinoma independent of therapeutic actionability. KRAS-TP53 co-mutation and the Mesenchymal transcriptomic subtype represent independent high-risk markers detectable on routine FFPE tissue. These features complement actionable alterations and may inform patient selection and clinical trial design.

P2, N=50, Completed, University College, London | Active, not recruiting --> Completed | Trial completion date: May 2026 --> Nov 2025 | Trial primary completion date: May 2026 --> Nov 2025

The second case involves a patient with metastatic micropapillary urothelial carcinoma with HER2 expression, refractory to platinum chemotherapy, avelumab maintenance, and enfortumab vedotin. These two observations illustrate the capacity of T-DXd to induce deep and complete metabolic remissions in distinct HER2-altered solid tumors. They support further development of HER2-targeted ADCs beyond traditional indications and highlight the value of FDG-PET/CT for assessing the depth of response to these agents.

By integrating tumor-restricted targeting and efficient intracellular drug delivery within a modular single-domain scaffold, vNAR R426 represents a next-generation theranostic platform capable of addressing intratumoral heterogeneity. This approach combines potent cytotoxic activity with immunofluorescence-based detection, thereby advancing the rational design of precision therapeutics for HER2-positive breast cancer.

The recent introduction of antibody-drug conjugates (ADCs), such as trastuzumab deruxtecan (T-DXd), has improved therapeutic outcomes for HER2-low breast cancer by demonstrating high efficacy in HER2-low tumors through efficient payload delivery...TME creates a barrier to the delivery of ADCs to tumor cells that show resistance to ADCs. This review article aims to highlight the current understanding of the biology of HER2-low breast cancer and its response to ADCs with reference to the tumor microenvironment.

Advances in genomic technologies, particularly circulating tumor DNA (ctDNA) analysis, have allowed longitudinal monitoring of tumor evolution, providing important insights into the mechanisms underlying resistance to targeted therapies. The aim of this review is to summarize the genomic landscape of mCRC and discuss current targeted therapeutic strategies in molecularly defined subgroups, with a particular focus on the mechanisms driving primary and acquired resistance.

Precision diagnostics now encompass next-generation sequencing (NGS)-based comprehensive genomic profiling, enabling identification of actionable alterations such as PIK3CA mutations, HER2 amplification, BRCA1/2 pathogenic variants, and NTRK fusions, each linked to approved therapeutic agents. The purpose of this review is to provide a comprehensive synthesis of current and emerging diagnostic modalities in breast cancer-from population-level screening to individualized molecular profiling-and to examine how integrative, multimodal diagnostic platforms are reshaping clinical decision-making in the era of precision medicine.