Canine Bone Sarcoma: Estimation of Rela- tive Risk as a Function of Body Size 1

SUMMARY-Larger canine breeds are subject to excess relative risk of primary bone sarcoma. Based on comparison of normal population samples and the 404 cases studied, the risk of bone sarcoma among giant dogs (over 80 Ibs.) is estimated to be no less than 61 times the risk among small dogs «20 Ibs.), and possibly as high as 185 times the risk for small dogs. A preliminary indication of increased risk of cancer other than bone sarcoma among larger breeds complicates interpretation of bone sarcoma risk values; if the larger breeds are subject to a greater probability of clinical attention for all types of cancer, the actual riskof bone sarcoma among giant dogsmay be as low as 29 times the risk among small dogs. Among giant dogs the risk of bone sarcoma is estimated to be no less than 5, and possibly as high as 30, times the risk of cancer other than bone sarcoma. Study results indicate the excess risk of bone sarcoma is characteristic of the larger breeds as a grouprather than of one or several particular breeds.-JNat Cancer Inst 36:1137-1150,1966