When Kasey bounded on the bed, her owner Dave Sabey knew something was wrong. The precocious, playful two-year-old pup, who performed this routine every night with great joy, jumped around nervously, heart racing. Assuming a torn ligament, Sabey brought her to their veterinarian, who took a radiograph of the Labrador’s rear left leg. It revealed a lesion on Kasey’s left distal tibia consistent with a diagnosis of osteosarcoma, the most common bone tumor found in dogs. This vet visit began a journey that ended at Penn Vet