Hi, Thanks for writing in. Cancer is the uncontrolled proliferation of abnormal cells involving a particular organ system. In colon cancer there is abnormal growth of the large bowel. Initial stages of colon cancer is treated with surgery followed by chemotherapy or radiation therapy. In about half of colon cancer patients, there might be spread to liver within 2 years of cancer detection. It might also involve the lungs and brain like in your grandfather. This happens because the cancer cells persist and travel through blood and multiply in target organs. Your grandfather has stage 4 cancer and with the best care and treatment his survival might be extended up to 2 years. Please discuss with his doctor and provide pain relief and keep him comfortable. He also requires healthy nutrition and adequate fluids to maintain his general condition. If seizures happen then anti epileptics are to be given. Please do not worry.