By analyzing data from thousands of dogs diagnosed with cancer, scientists from pet molecular diagnostics firm PetDx have come up with recommendations on when cancer screenings for these companion animals should begin. Cancer is the leading cause of death in adult dogs, and liquid biopsy has emerged as an effective tool to screen for cancer in the animals. But as it remains unclear when the best time to begin such screening is, PetDx researchers examined data on 3,452 dogs diagnosed with cancer, representing more than 120 breeds and a variety of cancer types. They report in PLOS One that the median age when dogs develop cancer is 8.8 years, with male animals receiving a diagnosis earlier than females and dogs that have been neutered being diagnosed at significantly later ages than their intact counterparts. Large- and giant-breed dogs were also diagnosed at younger ages than small dogs. When combining their findings with previously published research, the study's authors say that it is reasonable that annual cancer screening for dogs should start two years prior to the median age at cancer diagnosis for dogs of similar breed or weight, with a general recommendation for all animals to begin such screenings at age 7. The data generated in the study, they write, "may guide the incorporation of blood-based cancer screening into routine wellness evaluations for individual dogs, with the potential to improve the ability of veterinarians to detect cancer in the preclinical phase when the disease is more manageable.