NAVLE（北美执业兽医考题）Day 342

A 12-year-old Newfoundland is presented with left thoracic limb lameness. Pain localizes to the left shoulder and proximal humerus. Based on the radiographic findings, history, and signalment, osteosarcoma is high on the differential list. There are no metastatic lesions visible in three thoracic radiographic views. (not shown) What percentage of dogs with osteosarcoma will have visible pulmonary metastatic lesions at initial diagnosis?