Breed & Heredity
Clearly, the possibility of an inherited predisposition to cancer is of great concern to breeders and owners of affected breeds. Evidence of an inherited contribution to at least one common cancer comes from a recently published study showing that two primary subdivisions of lymphoma, B-cell lymphoma and T-cell lymphoma, segregate along breed-specific lines. (Modiano JF, Breen M, Burnett RC et al. Distinct B-cell and T-cell lymphoproliferative disease prevalence among dog breeds indicates heritable risk. Cancer Research 2005;65(13):5654-61).
In addition, some breeds have elevated rates of cancer wherever they are found around the world. This worldwide pattern suggests that these breeds were probably created from early founder dogs that carried genes that have been concentrated over time, and which convey increased cancer risk throughout the breed today. An example of such a breed is the Golden Retriever, which has a cancer rate of about 60 percent, with hemangiosarcoma and lymphoma representing approximately one-half of the breed cancers.
Breeds at Elevated Risk
Some breeds have less than the expected one-in-three incidence of cancer, while others are afflicted more frequently. Breeds at elevated risk for cancer, in general, or certain specific cancers include Boxers, Bernese Mountain Dogs, Flat-Coated Retrievers, German Shepherds, Golden Retrievers, Rottweilers, and Scottish Terriers, among others.