Thank you everyone for your response. We have a letter from doctor stating he has been maintaining his health with good diet exercise. On top of all this he does not drink or smoke. The doctor stated he would not have any issues for the next "couple of years". He did not state any specific timeline.
To answer nush781's question, it took him 6 months after CIC reviewed their application. We did not get any letter for follow up tests, I believe in your case there is some hope.
Submitting our application today, they basically stated the cost would be greater than $85K health and social combined. For social costs we are stating he would be living with us hence no special care or psychological cost incurred. For health, basically doctors letter and providing an action plan for the next 10 years.