Throughout my years of breeding dogs and just living I've witnessed folks that believe there is some kind of 'cancer' gene in DNA which simply is not true. Now I'm not saying after feeding DEAD DOG FOOD out of a plastic bag generation after generation doesn't have an effect on longevity and over all health on the next generation. it does! but here is no 'cancer' gene or 'cancer' lines of dogs. I am convinced cancer is what you ingest (eat and drink, breath) and your environment
So lets talk about Environment: things that are poison:
fleas collars
flea medication Any KIND some more than others even 'flea' shampoo
Internal Flea Medication is HORRIBLE!! Causes seizures among other things including death!
treating yard for fleas/ticks where dog Sniffs ground, Lays on ground, walks bare foot of ground
drinking out of plastic water hose
Glad plugs-in (or ANY kind of smelly stuff in your house)
Carpet cleaner
Air fresheners
Pine Sol!!! horrible!!
Carpet (your dog is breathing all these fiber plus the stuff the flame retardant chemicals the carpet was treated with )
even over doing essential oils. your dog can smell at least 10,000 times better than YOU!