Sugar,
My thoughts are with you and your Dad. Any kind of cancer can be a very scary thing for everyone involved. You'll both be in my thoughts
and prayers.
I choose from a number of things to do massage on my clientele w/ cancers. Most of the time, it's one of the wonderful creams from Soothing Touch - balancing or calming or lavender lotion - BUT, if there is any reaction to the smell or the texture from them whatsoever, then, I go to my "plan b" - a blend of safflower and sunflower oils mixed 50/50. That one has, to this point in time, not had any adverse reaction from my wonderful clients. And, it is readily absorbable, doesn't leave them feeling like a Buick in the shop for a lube job, and has a fairly neutral smell.
When my clients come to the office, they try a bit of the massage cream on their hand or foot, whatever they want to do. If they feel okay with it, that's what we use. Smells, textures, etc. can be heightened during chemo and radiation treatments, so, I do my best to let the clients take the lead in choosing what they fell will work well for them that particular day. I have used Neutrogena body creams and lotions, some really nice smelling Simply Basic melon scented body butter from Walmart, and other things that clients have brought with them to their sessions as well.
The gal that I spent so much time with choosing a skin lotion for her to rehab her burnt breast found that a lotion rich in shea butter was her best bet at that time - the scent soothed her mind, the lotion felt "heavenly" on the charred tissue [after the initial "ouch" of the rehydration" process].
Hopefully those suggestions will give you some ideas as to where to go with the emolliency issue for massage. If there are any other questions I can help you with, please feel free to pm me.
J