What medicine controls a dog’s mammary tumor?

A mammary tumor is best cured by early surgery — remove the mammary gland plus spay to control hormones. If the dog is too old for surgery, drugs like cyclophosphamide, vincristine and ifosfamide can help. Keep the environment stable and don't scold the dog often; less stress helps. Mammary tumors are common in unspayed females around 10, so spay early if you don't breed.