Abstract 108P
Background
The human epidermal growth factor receptor 2 (HER2/neu) play a predictive and prognostic role in colorectal cancer (CRC). Accurate evaluating of HER2 overexpression is required for selection and determination of eligible patients for HER2-directed therapy or primary resistance and poor response to anti-EGFR therapy. However, there is no currently established best practice for HER2 testing and interpretation in CRC. The purpose of this study was to validate and evaluate the performance of AmoyDx® HANDLE Classic NGS Panel (CP40) in assessing HER2 status by comparing it with HER2 IHC (4B5)/FISH analysis.
Methods
The CP40 is based on Halo-shape ANnealing and Defer-Ligation Enrichment (HANDLE) system technology, which allows high sensitivity in 40 key solid tumour genes qualitative detection and microsatellite instability (MSI) status assessment utilizing DNA and RNA. Performance of the CP40 was compared against the HER2 IHC/FISH assay according to the HERACLES scoring criteria using 805 CRC samples. Only samples with a ratio ERBB2:CEN17 ≥ 2 or staining equivocal (2+) or positive (3+) in at least 50% of cells were determined as HER2 IHC/FISH positive.
Results
CP40 and IHC/FISH assays were highly concordant in their assessment of HER2 status in CRCs (99.50%, 801/805, kappa = 0.892). Three conflicting results were negative in CP40 but were scored 2+ in 50-70% of the cells and identified as positive by IHC/FISH. One CRC scored as 3+ in 40% cells was determined to be negative by both CP40 and IHC/FISH. And all MSI CRCs were evaluated as HER2 negative by both CP40 and IHC. Table: 108P
Comparison of HER2 status determined from CP40 and IHC/FISH assays
| ERBB2 NGS-based CNV testing | ||||
| True | False | Total | ||
| HER2 IHC/FISH assay | Positive | 17 | 3 | 20 |
| Negative | 1 | 784 | 785 | |
| Total | 18 | 787 | 805 | |
| Kappa= | 0.892 | |||
| Overall coincidence rate = | 99.50% |
Conclusions
CRC-specific HER2 testing protocols and HER2 scoring criteria still needs to be optimised in a more refined and defined manner. HANDLE-based CP40, which combines DNA and RNA in NGS testing, is a potent tool for sensitive and reliable detection of HER2 status in clinical diagnostics.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
154P - Adverse events (AEs) as potential predictive factors of activity in patients with advanced hepatocellular carcinoma (HCC) treated with atezolizumab plus bevacizumab (AB)
Presenter: Mara Persano
Session: Poster Display
Resources:
Abstract
155P - Penpulimab combined with anlotinib and nab-paclitaxel plus gemcitabine (PAAG) as first-line treatment for advanced metastatic pancreatic cancer: A prospective, multicenter, single-arm, phase II study
Presenter: Juan Du
Session: Poster Display
Resources:
Abstract
156P - Phase II trial of second-line regorafenib in patients with unresectable hepatocellular carcinoma after progression on first-line atezolizumab plus bevacizumab: REGONEXT trial
Presenter: Jaekyung Cheon
Session: Poster Display
Resources:
Abstract
157P - T/N ratio and radiation dose delivered do not correlate with the development of Radioembolization-Induced Liver Disease (REILD) in Hepatocellular Carcinoma (HCC) following Y90 selective internal radiation therapy (Y90-SIRT): A retrospective, single tertiary centre cohort study
Presenter: Daniel Yang Yao Peh
Session: Poster Display
Resources:
Abstract
158P - Single-cell RNA sequencing via Endoscopic Ultrasoundguided Fine-Needle Biopsy (EUS-FNB) Pancreatic Biopsies uncovered an aggressive subclone with a poor prognosis
Presenter: Yung-yeh Su
Session: Poster Display
Resources:
Abstract
159P - Classical computer vision and modern deep-learning of pancreatic stroma histology features to diagnose cancer
Presenter: Abdelhakim Khellaf
Session: Poster Display
Resources:
Abstract
160P - Interim analysis of the NAPOLEON-2 study: Safety evaluation of nano-liposomal irinotecan with fluorouracil and folinic acid for advanced pancreatic cancer
Presenter: Wataru Kusano
Session: Poster Display
Resources:
Abstract
161P - Screening and COnsensus based on Practices and Evidence (SCOPE): Real-world survey on Japanese and rest-of-world practice patterns in resectable pancreatic cancer
Presenter: Elizabeth Smyth
Session: Poster Display
Resources:
Abstract
162P - Recurrence pattern of hepatocellular carcinoma patients receiving curative surgery of RFA: An update
Presenter: Long Chan
Session: Poster Display
Resources:
Abstract
163P - Chemotherapy versus palliative radiotherapy in advanced inoperable gall bladder cancer
Presenter: Vimal Sekar
Session: Poster Display
Resources:
Abstract