Clinical validation of a next-generation sequencing-based multi-cancer early detection “liquid biopsy” blood test in over 1,000 dogs using an independent testing set: The CANcer Detection in Dogs (CANDiD) study

Andi Flory, Kristina M. Kruglyak, John A. Tynan, Lisa M. McLennan, Jill M. Rafalko, Patrick Christian Fiaux, Gilberto E. Hernandez, Francesco Marass, Prachi Nakashe, Carlos A. Ruiz-Perez, Donna M. Fath, Thuy Jennings, Rita Motalli-Pepio, Kate Wotrang, Angela L. McCleary-Wheeler, Susan Lana, Brenda Phillips, Brian K. Flesner, Nicole F. Leibman, Tracy LaDueChelsea D. Tripp, Brenda L. Coomber, J. Paul Woods, Mairin Miller, Sean W. Aiken, Amber Wolf-Ringwall, Antonella Borgatti, Kathleen Kraska, Christopher B. Thomson, Alane Kosanovich Cahalane, Rebecca L. Murray, William C. Kisseberth, Maria A. Camps-Palau, Franck Floch, Claire Beaudu-Lange, Aurélia Klajer-Peres, Olivier Keravel, Luc André Fribourg-Blanc, Pascale Chicha Mazetier, Angelo Marco, Molly B. McLeod, Erin Portillo, Terry S. Clark, Scott Judd, C. Kirk Feinberg, Marie Benitez, Candace Runyan, Lindsey Hackett, Scott Lafey, Danielle Richardson, Sarah Vineyard, Mary Tefend Campbell, Nilesh Dharajiya, Taylor J. Jensen, Dirk van den Boom, Luis A. Diaz, Daniel S. Grosu, Arthur Polk, Kalle Marsal, Susan Cho Hicks, Katherine M. Lytle, Lauren Holtvoigt, Jason Chibuk, Ilya Chorny, Dana W.Y. Tsui

Research output: Contribution to journalArticlepeer-review

22 Scopus citations


Cancer is the leading cause of death in dogs, yet there are no established screening paradigms for early detection. Liquid biopsy methods that interrogate cancer-derived genomic alterations in cell-free DNA in blood are being adopted for multi-cancer early detection in human medicine and are now available for veterinary use. The CANcer Detection in Dogs (CANDiD) study is an international, multi-center clinical study designed to validate the performance of a novel multi-cancer early detection “liquid biopsy” test developed for noninvasive detection and characterization of cancer in dogs using next-generation sequencing (NGS) of blood-derived DNA; study results are reported here. In total, 1,358 cancer-diagnosed and presumably cancer-free dogs were enrolled in the study, representing the range of breeds, weights, ages, and cancer types seen in routine clinical practice; 1,100 subjects met inclusion criteria for analysis and were used in the validation of the test. Overall, the liquid biopsy test demonstrated a 54.7% (95% CI: 49.3–60.0%) sensitivity and a 98.5% (95% CI: 97.0–99.3%) specificity. For three of the most aggressive canine cancers (lymphoma, hemangiosarcoma, osteosarcoma), the detection rate was 85.4% (95% CI: 78.4–90.9%); and for eight of the most common canine cancers (lymphoma, hemangiosarcoma, osteosarcoma, soft tissue sarcoma, mast cell tumor, mammary gland carcinoma, anal sac adenocarcinoma, malignant melanoma), the detection rate was 61.9% (95% CI: 55.3–68.1%). The test detected cancer signal in patients representing 30 distinct cancer types and provided a Cancer Signal Origin prediction for a subset of patients with hematological malignancies. Furthermore, the test accurately detected cancer signal in four presumably cancer-free subjects before the onset of clinical signs, further supporting the utility of liquid biopsy as an early detection test. Taken together, these findings demonstrate that NGS-based liquid biopsy can offer a novel option for noninvasive multi-cancer detection in dogs.

Original languageEnglish (US)
Article numbere0266623
JournalPloS one
Issue number4 April
StatePublished - Apr 2022

Bibliographical note

Funding Information:
This study received funding from PetDx. The funder had the following involvement with the study: study design, data collection and analysis, decision to publish, and preparation of the manuscript. Study sites were compensated for submission of samples and for collection and QC of clinical data. The authors thank all the dogs in the CANDiD study and the humans who love and care for them. Without their support and contributions, this study would not have been possible. The authors would also like to thank Jason Loftis and Dominique Lau for assistance with developing the tables, figures, and graphics in this manuscript, as well as Vu Q. Nguyen, Amanda Nguyen, the entire PetDx laboratory team for assistance with data generation. Additionally, the authors would like to thank Oncovet Clinical Research, VCA Clinical Studies, the doctors and staff at Flint Animal Cancer Center Colorado State University, the College of Veterinary Medicine at the University of Missouri, Veterinary Specialty Hospital of San Diego, Veterinary Specialty Hospital of North County, Southeast Veterinary Oncology and Internal Medicine, Bridge Animal Referral Center, The Animal Medical Center, the team at the University of Guelph Institute for Comparative Cancer Investigation at the Mona Campbell Centre for Animal Cancer OVC HSC U of Guelph, Governor Animal Clinic Inc., University of Minnesota College of Veterinary Medicine, Veterinary Specialty Hospital of Hong Kong, Oncovet, Clinique V?t?rinaire de la Pierre Bleue, Eiffelvet, Clinique V?t?rinaire SeineVet, Clinique V?t?rinaire Mazetier, Evidensia Animal Hospital Barendrecht, VCA Metroplex Animal Hospital, VCA Valley Oak Veterinary Center, City Paws Home Health, Prices Creek Veterinary Services, Carlsbad Animal Hospital, Oceanside Veterinary Hospital, Amici Pet Hospital of Little Italy, Colony Veterinary Hospital, Carriage Hills Animal Hospital, and the Integrated Oncology Service at The Ohio State University Veterinary Medical Center and the Blue Buffalo Veterinary Clinical Trials Office (BBVCTO). Additionally, the authors would like to give special thanks to Deirdre Stuart, Victoria Sabine, Aspen Schreiner, Kayla Hufstetler, Olivia Uzan, Kate Wotrang, Betsy Peet, Sarah Kenney, Sofya Gefter, Daisy Granados Peji, Alma D. Galicia Ortiz, Natasha Shoemaker, Allison Ball, Dr. Kristina Bowles Miller, Marissa Kroll, Dr. Sarah Roberts, Dr. Andrea Monta?o Hernandez, Dr. Agata Rybicka, Juliette Blondiau, Emmanuel Bouchaert, Kathleen Stuebner, April Jackson, Sara Pracht, Kelly Bergsrud, Anastasia Glahn, Dana Jennings, Justin Paul, Angela Wilson, Beth Anderson, and Dana Nielsen.

Publisher Copyright:
© 2022 Flory et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.


  • Animals
  • Biomarkers, Tumor/genetics
  • Dogs
  • Early Detection of Cancer
  • Hemangiosarcoma
  • Hematologic Tests
  • High-Throughput Nucleotide Sequencing/methods
  • Humans
  • Liquid Biopsy
  • Osteosarcoma

PubMed: MeSH publication types

  • Research Support, Non-U.S. Gov't
  • Journal Article


Dive into the research topics of 'Clinical validation of a next-generation sequencing-based multi-cancer early detection “liquid biopsy” blood test in over 1,000 dogs using an independent testing set: The CANcer Detection in Dogs (CANDiD) study'. Together they form a unique fingerprint.

Cite this