Anita,
For the longest time I could not seem to gain any weight, and I still have swallowing difficulties, but now, about 14 months after radiation treatments ended, I have reached my ideal weight(about 5 pounds less than I weighed when I started). I have done it on a fairly limited diet...I eat matzo ball soup from a local deli a couple of meals a day, cereal and banana in the morning, occasional pasta, fish, or Chinese food with chicken, and 2 to three chocolate milkshakes that I make at home each day with whole (lactose free) milk and real ice cream. I also drink one or two cans of Boost plus a day and some yogurt.
Good luck,
Danny G.