Metastatic Bone Cancer Treatment?

Hi all! I am here for my grandfather. He is 65 years old and he is suffering from metastatic bone cancer. He was also a high blood pressure patient and diabetic since he was 50 years old. All these days he was managing all his diseases pretty well through diet, exercise and medication. But this cancer problem is way too much for him. Its in his pelvic region which gives him constant unbearable pain. I want to know the metastatic bone cancer treatment?