Liquid biopsy screening for early cancer detection in working dogs – Presented by Katherine M. Lytle, DVM, MPH, MS

Cancer is the leading cause of mortality in dogs, and working dogs are no exception. A novel technology called liquid biopsy may offer an effective, non-invasive screening test for safe and early detection of cancer in working dogs, maximizing the chances of a favorable clinical outcome with the goal of extending the working dog’s life and career. 

Blood samples from an all-comers cohort of 191 cancer-diagnosed dogs and 188 presumably cancer-free dogs were subjected to DNA extraction, proprietary library preparation, and next-generation sequencing. Sequencing data were analyzed using an internally developed bioinformatics pipeline to detect genomic alterations associated with the presence of cancer. 

The overall sensitivity in cancer-diagnosed subjects was 48% (92/191). Of 188 samples from presumably cancer-free dogs, 180 tested negative (putative ‘true negatives’) and 8 tested positive (‘putative false positives’, pFP). In at least 2 pFP cases, patients were diagnosed with cancer 6-7 months following blood collection and were excluded from final performance analyses, resulting in a minimum test specificity of 97%. 

A novel, multi-cancer early detection (MCED) liquid biopsy test has demonstrated performance comparable to commercially available MCED testing options in humans. This test has shown the potential for detecting genomic markers of cancer months prior to the development of clinical signs. Early detection and treatment of cancer are key determinants of optimal clinical outcomes. When employed as a screening tool in the annual workup, a liquid biopsy test has the potential to extend the working dog’s career.