If the dog is smart or has been specially trained, it will bark at the patient after sniffing out the cancer, but not all dogs can sniff out the cancer and express it accurately. Although research shows that dogs can sniff out cancer with an accuracy rate of up to 71%, the results vary depending on the breed of dog. It is generally difficult for ordinary dogs raised at home to sniff out cancer and express it, so do not rely entirely on dogs. , it is best to go to the hospital for examination.