Driving with advanced PC

I really can't think of the reason for this.  My brother-in-law lived with advanced cancer which had spread to his bones and spine for many years and didn't stop driving though obviously he and his wife shared the driving on a long run but he still did a lot of driving as his wife doesn't like driving.  I would contact the specialist nurse and ask for the reason for this.  There are potential side effects side effects of fatigue and  from the Hormone Treatment so saying that he shouldn't drive more than he has to is fine so when he feels OK to drive and is not over tired I would imagine he is as able to drive as any of us on a day to day basis.  The nurse didn't say not to drive just not to drive more than he needs to so if he wants to go somewhere you are not going I don't see the need for you to go out of your way to drive him if he feels well enough to drive.  Definitely check this out by contacting the specialist nurse as I too would like to know the reason for this.  I would also like to know if anyone else has been told this.