Which skeletal region is primarily affected by osteosarcoma in small animals?

Osteosarcoma is a type of bone cancer that is most frequently found in the metaphysis of long bones in small animals. This area is located between the diaphysis (the shaft of the bone) and the epiphysis (the end part of a long bone). The metaphysis is particularly susceptible to the rapid growth of osteosarcoma due to the presence of active bone growth and remodeling that occurs in young, rapidly growing animals, which is where this tumor commonly arises.

In the metaphysis, the increased vascularity and bone turnover provide an environment conducive to the formation of malignant tumors like osteosarcoma. The tumor typically originates from the osteoblasts, which are the cells responsible for bone formation, leading to the aggressive bone destruction characteristic of the disease. When diagnosing and treating osteosarcoma, understanding its common location can significantly impact clinical decisions and outcomes.