# Lessons from a National Liquid Biopsy Program to Provide Cancer Testing and Treatment for Patients with Advanced Solid Tumors

## TL;DR

A national liquid biopsy program in Canada successfully provided fast, less invasive cancer testing for thousands of patients, improving treatment options and healthcare efficiency.

## Contribution

Demonstrates the feasibility and benefits of a large-scale, cost-effective liquid biopsy program for advanced cancer patients in Canada.

## Key findings

- 97% of 4229 patients received high-quality liquid biopsy results within 8 days on average.
- Over 50% of patients had detectable cancer mutations in their blood, enabling targeted treatment options.
- Combining liquid biopsy with tissue biopsy was found to be cost-saving and improved health outcomes.

## Abstract

Detection of the patient-specific mutations present in an individual tumor is critical for the selection of the best treatment option for cancer patients. Liquid biopsy (LBx) allows the detection of such mutations in a less invasive manner and is often faster than traditional tissue biopsy. Here we report a successful experience of running an LBx program for Canadian patients with advanced solid tumors. The testing was done over the course of three years for >4000 patients referred from >150 institutions. A total of 97% of patients received high-quality testing results within an average 8 days, which provided oncologists with actionable information for treatment selection. This study has demonstrated the feasibility and growing demand for LBx testing in Canada with the potential to improve patient outcomes, while allowing the healthcare system to operate more efficiently.

Personalized cancer treatment depends on the accurate and timely detection of the patient tumor variants. LBx enables minimally invasive tumor mutation profiling. We report results of a pan-Canadian LBx program for patients with advanced solid tumors. Plasma samples were tested at Imagia Canexia Health accredited laboratory using the clinically validated Follow It 38-gene panel. A proprietary platform was used to identify clinically relevant variants in the circulating tumor DNA and report results following accepted international guidelines on clinical significance. A total of 4229 eligible patients submitted samples for LBx testing, and reports for 97% of them were delivered within ~8 days. More than 80% of Canadian oncologists from >150 institutions across 12 provinces (11% from rural centers) participated in the project. The patient cohort consisted mostly of advanced or metastatic lung, breast, and colon cancers. ctDNA mutations were detected in >50% of cases, and clinical trials were recommended for 76% of all participants. Health economics modeling analysis found that Follow It® in combination with tissue biopsy was cost-saving and resulted in an additional 0.1138 QALYs gained relative to tissue biopsy alone. The successful pan-Canadian implementation of a cost-effective, robust LBx testing program demonstrated its sustained demand and feasibility, and its potential economic and health benefits.