Abstract 102P
Background
Neurotrophic tropomyosin receptor kinase (NTRK) gene fusions are actionable biomarkers for cancer therapy. They have been identified in over 25 cancers and their prevalence varies across tumors. This study aims to assess the adoption of NTRK testing in common cancers, diagnostic tests used, & test results, in Europe & Asia, in 2020.
Methods
This study was conducted using Oncology Dynamics™, an IQVIA cross-sectional survey collecting drug-treated, anonymized, real-world patient data. 94,027 patients (pts) in France, Germany, Italy, Spain, & UK and 33,891 pts in China, Japan, & S. Korea were analyzed. These included all solid tumor pts collected in 2020, excluding clinical trials.
Results
The NTRK test rate was low in all countries. In all regions, Next-Generation Sequencing (NGS) was the predominantly used detection tool. A two-step diagnostic test, using Immunohistochemistry (IHC) or Fluorescence in situ hybridization (FISH) as a screening tool, followed by NGS, was also employed. Asia reported a higher use (72%) of direct NGS than Europe (46%). Refer to the table for NTRK test rate and diagnostic test usage by country. 3% of investigated pts had been tested for NTRK. Possibly due to a preselection strategy, our study identified higher frequency of NTRK fusions in esophageal, liver, prostate, melanoma, & breast cancer, compared to the reported prevalence in these indications. Our study confirmed higher prevalence of NRTK+ in Microsatellite Instability-High (MSI-H) colorectal cancer compared to MSI-Stable (MSI-S) colorectal cancer. We were able to demonstrate the same trend of higher NTRK mutation frequency in MSI-H compared to MSI-S in liver and esophageal cancers. In liver cancer, NTRK fusions were even 8x more prevalent in MSI-H than in MSI-S pts. Table: 102P
| Country | NTRK test rate | Diagnostic tests used |
| Germany | 5.6% | NGS only (48%) IHC-NGS (24%) FISH-NGS (7%) Others (21%) |
| Spain | 4.1% | NGS only (53%) IHC-NGS (20%) FISH only (6%) Others (21%) |
| France | 3.7% | NGS only (52%) IHC-NGS (29%) FISH-NGS (6%) Others (13%) |
| Japan | 3.4% | NGS only (60%) IHC-NGS (17%) FISH-NGS (12%) Others (11%) |
| S. Korea | 2.3% | NGS only (95%) IHC-NGS (5%) |
| Italy | 1.6% | NGS only (41%) IHC-NGS (18%) FISH-NGS (8%) Others (33%) |
| UK | 1.5% | NGS only (50%) IHC-NGS (17%) FISH-NGS (13%) Others (20%) |
| China | 1.3% | NGS only (83%) IHC-NGS (6%) FISH-NGS (1%) Others (10%) |
Conclusions
NTRK testing should become part of standard diagnostic process, to support successful selection of pts for targeted therapies. Asia has seen higher adoption of direct NGS testing than Europe. MSI-H pts presented with more NTRK fusions than MSI-S pts.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
IQVIA.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.