Hi there ..  Maybe you can go with her for support .. on my appointment I was told what it was and what they could do and a plan of the way forward .. my Dr gave me a couple of weeks so I could make my mind up on what I wanted for me ... every one is different and may be other then my experience  ... go with questions you would like to know .. then you can talk it over with your nan as it's sometimes depends what she wants as her age may mean she needs to do what she feels comfortable  for her .. 

Sorry I can't be more helpfully but one thing you can do is phone macmillan help line where they are trained nurses and can advise and listen to how you feel too .. I called them a couple of times and they really  helped .. all the best to you .. big hug xx