Osteosarcoma of the hip in Greyhounds

Osteosarcoma (OSA) is the leading cause of death in retired racers.  The most common sites are the proximal humerus (shoulder bone), the distal femur (thigh bone), and the proximal tibia. OSA of the proximal femur (near the hip joint) is extremely rare in dogs, but common in Greyhounds. In addition, Greyhounds literally have no hip dysplasia.

When an adult dog has hip pain, it is usually attributed to hip dysplasia and osteoarthritis; when a Greyhound has hip pain, bone cancer should be suspected. Below is a radiograph of a femoral neck OSA in a Greyhound; the black area (yellow arrow) is due to bone destruction (lysis). 

An ultrasound-guided fine needle aspirate (FNA) frequently confirms the diagnosis (below).

Fine needle aspirate of an osteosarcoma