Unfortunately, once you are burned from radiation, particularly in the pelvic region, it is difficult to do much for it. It makes me so mad that the rad oncs don't tell people ahead of time because there are many many options out there to avoid getting burned. In my opinion, Aquaphor is useless. Try aloe vera-pure and clear, no dyes no alcohol. You need to know that alcohol is a big no no on radiated skin. Radiation not only burns, but dries and thins the skin out. Moisturizers are good, IF your mom can tolerate them at this point because she is burned. Try finding out without alcohol or with a very little amount in it. I also highly recommend pure cocoa butter to help with the burning and other issues. One moistureizer you can try is Johnson & Johnson's 24Hour Softlotion. Can usually be found in the baby aisle. To help protect certain areas, use either bag balm or desenex. However, WASH EVERYTHING off completely before the next treatment. Make sure your mom is staying very well hydrated to help with other issues. Also, try and find this Radiagel or Radiacream by Carrington Labs. It also comes in a Rx strength, but you can order the radiacream directly from Carrington on their website. Tremendous product. Another thing is to make sure your mom is NOT using regular soap. Use only gylcerin based soaps. All of these, however, might just be too painful since she is already burned.
Also, since anal/rectal squamous cell is treated differently than adenocarcinoma, I might suggest you check into this yahoo group designed specifically for them. When I was first diagnosed, I didn't realize the difference and only saw the word rectal and joined. I am still a member and am so impressed with their compassionate, knowledable and informed members.
http://health.groups.yahoo.com/group/anal-cancer/You will have to join, but just ask questions, go through their databases, etc. Wonderful group of people and very helpful.
Jaynee