Dogs are very painful when they are in the late stage of cancer. In addition to physical pain and mental torture, death can occur at any time. When the owner discovers that the dog is feeling unwell, he should take him to the hospital for examination as soon as possible. Treatment can help relieve the dog's pain. Generally, it cannot be cured in the advanced stage. The owner can feed the dog some food he likes and spend more time with the dog so that he can leave peacefully.