Osteosarcoma is an aggressive, painful bone cancer primarily affecting large breed dogs. Welfare-centered decision making guides owners through difficult treatment and end-of-life choices.
Osteosarcoma causes severe, escalating bone pain from tumor invasion of the cortex. The pain is often described as among the most severe in veterinary medicine and progresses rapidly. Without treatment, most dogs reach a welfare threshold requiring euthanasia within 1-4 months. Treatment decisions involve weighing the significant demands of amputation surgery and chemotherapy against the quality and quantity of additional life achieved. Dogs tolerate amputation well and most are mobile within days on three legs. Palliative care with pain management provides good quality time without surgery for owners who choose not to pursue curative treatment. The welfare focus throughout is maintaining comfort and dignity.