Hi there being in Vancouver you are likely being treated at a cancer hospital. Chances are way will insist one be put in. She can resist this but being that she s 60 It may be better for her to have one to help when things get painful. It really depends on her pain tolerance, and how difficult you think it will be to get her to eat. She will have to have nutrition. I had one placed as my hospital insisted, but I couldn't use it so I muddled though without and was okay but I forced myself to take my nutrition even when things were bad. If she can't do that then a peg may be a good idea particularly if she's small to average sized.
Regardless of a peg or not she need to remember to swallow all the time. best of luck.