TEST:

TruSight Oncology 500 ctDNA v2

This study successfully optimized the Illumina TruSight Oncology 500 ctDNA v2 library preparation using an automated liquid handling system. The experience may be beneficial for other laboratories in implementing the ctDNA NGS assay.

The TSO500 ctDNA v2 assay with automated library prep on the NGS STAR MOA liquid handler has demonstrated performance comparable to manual library prep and offers a high-throughput solution to enable comprehensive genomic profiling with a faster chemistry, more flexible workflow, and easier-to-use reagent kit.

In this pilot study, the TSO500 ctDNA v2 provided workflow enhancements with decreased overall turnaround time compared to TSO500 ctDNA v1, as well as low DNA input requirement, excellent sensitivity, and high accuracy.

This study suggests that gDNA contamination has minimal impact on the performance of TSO500 ctDNA v2, even with gDNA input 20 times higher than ctDNA. The high tolerance of TSO500 ctDNA v2 to gDNA contamination is likely due to its chemistry, which includes no initial fragmentation, size selection during bead cleanup, and a capture and hybridization process favoring shorter DNA fragments (cfDNA) over longer ones (gDNA).

Together, these results demonstrate that the NovaSeq X series of instruments generates equivalent analytical results with overall reduced sequencing time, enabling a <3.5-day turnaround time.

CONCLUSION The findings suggest that ctDNA testing can identify additional actionable genomic alterations not detected by tissue-based NGS, highlighting its potential to complement traditional tissue profiling in the management of lung cancer especially in metastatic cases. This integration could significantly enhance the precision of mutation detection and treatment planning.

"Illumina Inc...today announced it has expanded its oncology menu for NovaSeq™ X Series customers. The company began offering the newly verified high-throughput version of TruSight™ Oncology 500 (TSO 500 HT), and the latest version of its distributed liquid biopsy research assay, TruSight Oncology 500 ctDNA v2 (TSO 500 ctDNA v2), in recent months."

Detection rate by ctDNA profiling is higher compared with RNA-based approaches and it is of prognostic significance.

Precision evaluation showed >99% precision for targeted small DNA variant calls.Conclusion Together these results demonstrate > 99.999% analytical specificity with high analytical sensitivity to AFs ranging from 0.2% to 0.4% depending on variant class. This performance was achieved using a lower recommend input of 20ng of cfDNA and utilizes a workflow that reduces total turn-around time and hands-on time while still delivering all key biomarker data available from the TSO 500 gene panel.

"Illumina Inc...announced a new generation of its distributed liquid biopsy assay for genomic profiling. The new TruSight Oncology 500 ctDNA v2 (TSO 500 ctDNA v2) is a research assay that enables noninvasive comprehensive genomic profiling (CGP) of circulating tumor DNA (ctDNA) from blood when tissue testing is not available, or to complement tissue-based testing....Expected in the first half of 2024, automation-enabled kits and method for TSO 500 ctDNA v2 will allow laboratories to scale with the growing demand for this technology."

Conclusions Fusions detected from ctDNA CGP showed promising clinical utility based on the observed response to the targeted agents. Adjustments in the cutoff and correction of the effect from tumor fraction is required for ctDNA-derived TMB/MSI.