Prognostic factors in dogs with osteosarcomas of the flat or irregular bones.

The medical records of 45 dogs with histopathologically confirmed osteosarcomas arising from flat or irregular bones were reviewed. Thirty-five percent of the dogs eventually developed metastases. Telangectatic tumors and tumors arising from the rib and scapula had the highest prevalence of metastases. Survival times were short, with an overall median survival time of 120 days. Anatomic site, body weight, and completeness of surgical excision were found to be prognostic factors. Dogs with mandibular osteosarcomas in this study had shorter survival times than those times recently reported. 21 Local recurrence was the most common cause of death or euthanasia in this population of dogs.