Canine Osteosarcoma: Anatomical Distribution and Breed Predisposition in a Five-Year Retrospective Study

Osteosarcoma is the most common primary malignant bone tumor in dogs and predominantly affects large and giant breeds. A five-year retrospective study was conducted to evaluate the anatomical distribution and breed predisposition of osteosarcoma cases presented to a Referral Veterinary polyclinic cum TVCC of the Indian Veterinary Research Institute (IVRI). A total of 48 cases were recorded during the study period (2020-25). The distal femur was the most frequently affected site (16 cases; 33.3%), followed by the distal radius/ulna (13 cases; 27.1%), proximal humerus (11 cases; 22.9%), and distal tibia (6 cases; 12.5%), while other skeletal locations accounted for 2 cases (4.2%). Breed-wise distribution revealed a predominance in Rottweilers (13 cases; 27.1%), followed by Golden Retrievers (10 cases; 20.8%) and Labrador Retrievers (9 cases; 18.8%). Other affected breeds included Saint Bernard (3 cases), German Shepherd Dog (3 cases), American Bully (2 cases), and Great Dane (2 cases), while other breeds accounted for 6 cases. The findings indicate that osteosarcoma occurs predominantly in the metaphyseal regions of long bones and shows a higher prevalence in large and giant breed dogs.