Next-generation sequencing-based liquid biopsy can be used for detection of residual disease and cancer recurrence monitoring in dogs

Abstract

ObjectiveThe purpose of this study was to evaluate the performance of a next-generation sequencing-based liquid biopsy test for cancer monitoring in dogs. SamplesPre- and post-operative blood samples were collected prospectively from dogs with confirmed cancer diagnoses originally enrolled in the CANcer Detection in Dogs (CANDiD) study. A subset of these dogs also had longitudinal blood samples collected for recurrence monitoring. MethodsAll patients had a pre-operative blood sample collected (after diagnosis but prior to surgical intervention) in which a cancer signal was detected, and had at least one post-operative sample collected. Clinical data were collected for all patients and used to assign a clinical disease status for each follow-up visit. ResultsFollowing excisional surgery, in the absence of clinical residual disease at the post-operative visit, patients with Cancer Signal Detected results at that visit were 1.95-times as likely to have clinical recurrence within 6 months compared to patients with Cancer Signal Not Detected results. In the subset of patients with longitudinal liquid biopsy samples that had clinical recurrence documented during the study period, 73% (8/11; 95% CI: 39 - 93%) of patients had Cancer Signal Detected in blood prior to or concomitant with clinical recurrence; in the 6 patients where molecular recurrence was detected prior to clinical recurrence, the median lead time was 168 days (range: 47 - 238). Clinical RelevanceNext-generation sequencing-based liquid biopsy is a non-invasive tool for cancer monitoring in dogs that can be used as an adjunct to current standard-of-care clinical assessment methods.