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
519P - Final results and subgroup analysis of ORIENTAL: A phase IIIB study of durvalumab plus platinum-etoposide in first-line treatment of Chinese patients with extensive-stage small-cell lung cancer (ES-SCLC)
Presenter: Ying Cheng
Session: Poster Display
Resources:
Abstract
520P - Role of atezolizumab in controlling CNS progression in ES-SCLC
Presenter: Yoon Namgung
Session: Poster Display
Resources:
Abstract
521P - Camrelizumab combined with chemotherapy and apatinib as first-line therapy for extensive-stage small cell lung cancer: A phase II, single-arm, exploratory research
Presenter: Yanbin Zhao
Session: Poster Display
Resources:
Abstract
522P - Durvalumab plus etoposide and carboplatin for extensive-stage small cell lung cancer with mild idiopathic interstitial pneumonia
Presenter: Ichiro Nakachi
Session: Poster Display
Resources:
Abstract
523P - Camrelizumab plus apatinib as maintenance treatment in patients with extensive-stage small cell lung cancer who were responding or stable after standard first-line chemotherapy (CAMERA): Results from a single-arm, phase II trial
Presenter: Qi Wang
Session: Poster Display
Resources:
Abstract
524P - Treatment pattern and overall survival by lines of therapy among patients with advanced small cell lung cancer in Taiwan
Presenter: Kelly Huang
Session: Poster Display
Resources:
Abstract
525P - Development of diagnostic prediction score for malignant pleural effusion in lung cancer: MPE-Lung score
Presenter: Chaichana Chantharakhit
Session: Poster Display
Resources:
Abstract
526P - Burden and trends of tracheal, bronchus, and lung (TBL) cancer in Southeast Asia, East Asia, and Oceania from 1990-2019, and its projection of deaths to 2040: A benchmarking analysis
Presenter: Monika Chhayani
Session: Poster Display
Resources:
Abstract
527P - Efficacy of intraventricular chemotherapy with pemetrexed for leptomeningeal metastasis from lung adenocarcinoma: A retrospective study
Presenter: Fang Cun
Session: Poster Display
Resources:
Abstract
528P - Socioeconomic determinants of access to standard-of-care treatments in advanced and metastatic NSCLC in Hong Kong: A territory-wide study
Presenter: Ka Man Cheung
Session: Poster Display
Resources:
Abstract