Cancer “young” and “old”
US veterinarians studied risk factors for cancer in younger dogs through a large survey published in PLOS ONE.
Researchers found that non neutered dogs and purebreds weighing more than 75 kilograms tend to develop cancer earlier than other dogs. Additional risks included male sex and breed. The study highlighted that Bichon Frise dogs live the longest without cancer, while Mastiffs and St Bernards are among breeds with the earliest onset of cancer.
It is important to note that the article does not report a higher overall cancer rate in any breed. The emphasis was on the age at which cancer first appears. The authors suggest some animals should be examined earlier in life, according to a veterinary oncologist who commented on the study.
Because of this, regular veterinary visits are essential even for young and seemingly healthy dogs. Experts point out that many clinics offer examinations similar to human health checks.
For practical guidance, up to age ten owners should consider annual veterinary visits that include vaccinations, blood work, routine exams, and abdominal ultrasounds. A chest x ray may be considered, though it is not particularly informative for detecting cancer or metastasis. After ten years, examinations are advised twice a year, as noted by a veterinary oncologist.
racial influence
Earlier canine cancer studies show that breeds differ not only in when cancer appears but also in their likelihood of developing tumors. A contributing factor is defects in the TP53 gene, which controls the production of the p53 protein. This protein helps regulate the cell cycle and prevents malignant transformation in many mammals with well-studied genomes.
Some breeds carry dangerous TP53 mutations. These include several retriever lines and Bernese Mountain Dogs, with a genetic risk for malignant tumors reaching up to half of affected dogs.
Scottish Terriers face a higher risk of bladder cancer. German Boxers, Dobermans, and Rottweilers are more prone to lymphomas. Pugs show a higher risk for mast cell tumors, and German Shepherds for hemangiosarcoma, a cancer of blood vessel tissue. Giant breeds often face a higher risk of osteosarcoma affecting the bones.
Thus, if a Great Dane shows lameness, it should be considered a potential sign of osteosarcoma until proven otherwise. A veterinary expert explained that cancer might be suspected when body weight declines and fatigue appear, but the most important sign is a loss of muscle mass. Weight loss alone often appears in later stages when treatment becomes tough, so any reduction in body weight should be evaluated by a veterinarian.
vaccine induced sarcoma, virus induced skin cancer
Beyond the listed risks, exposure to tobacco smoke and obesity can raise cancer risk in dogs. Research indicates that cancer in dogs is not tied to a single type of food, whether natural or industrial. Vaccinations themselves do not show a clear effect on cancer risk. While cats have rare instances of sarcoma at vaccination sites, it is extremely uncommon in dogs. Some vaccines are given away from the shoulder to the inner knee crease or base of the tail to ease treatment if a sarcoma develops. Owners should not avoid vaccines due to cancer fears, since some viruses can cause cancer or weaken immune defenses, allowing cancers to grow if left unchecked.
Dogs harbor specific papillomaviruses that raise the risk of certain cancers such as squamous cell skin cancer. The virus can be passed from mother to puppy or through saliva during shared meals or toys. Humans also carry papillomaviruses, including some oncogenic forms, but infections are species specific, so cross species transmission is not possible, according to a veterinary expert.
drug phobia
Some owners delay treatment because they hear phrases like this may be just a bump that will go away. But what is true for humans is not the same for dogs. If a lump is felt under the skin, it deserves closer evaluation.
Subcutaneous lesions in dogs often appear later in life. Surgery to remove them is not necessarily dangerous. Age alone is not a reason to avoid anesthesia. Most patients tolerate anesthesia well, with clinicians weighing risks carefully. If a tumor is suspected, a biopsy is performed to determine its nature.
While there is no reliable animal cancer screening program today, advances may come in the future. Tumors release substances into blood or urine, sometimes as DNA or RNA traces or as distinctive proteins. The diagnostic method for these substances is called liquid biopsy. It is minimally invasive, using a blood or urine sample, and can identify the tumor type. Veterinarians note that liquid biopsy is not yet routine in veterinary practice.
Experts in the study indicate liquid biopsy could become a primary diagnostic tool for some canine cancers, though it is not universal. Each tumor secretes a specific protein, so a test may identify a cancer type, but each tumor requires its own laboratory kit, which are not universally available. In North America and Europe, a form of liquid biopsy is already used for bladder cancer: a urine test for a tumor protein that signals disease, a point highlighted by a veterinary expert.