Hi Susan, Weight gain was a problem for me too during chemo. I started at 68kg in Feb, and went up to nearly 78kg by the end of my 12 wks of TCH in July. Some cycles I weighed myself before chemo, and then the day after found I had shot up about 6kg. It would then slowly drop a couple of kilos through the cycle, but when I had my next treatment it would still be higher than the start of that cycle. I tried to be careful during chemo, and think I would have put on a lot more without my daily walks.But I also didn't want to suffer any more than I was already suffering, and depriving myself to lose weight did not seem possible. I tried to eat reasonably healthily. Also, a lot of people talk about putting on about 20kg or more, so 10kg is not to bad.
At the end of the chemo I discussed it with my Oncologist. She said that at that point part of my weightgain (about a kilo) was fluid retention and the rest was fat. I think it was caused by the food I ate when going through chemo. Sometimes, I really wanted comfort food, and when I had diarhoea I ate a lot of white bread and cheese to slow my digestive system down, and when I had constipation I snacked a lot on dried fruit.
So now I am trying to get down to 62kg which is my ideal BMI and my oncologist recommended this as healthy for me. I am now down to 65-66kg. I lost the weight by walking for about an hour each day and dropping to 600calories a day for 4 days in the middle of each Herceptin treatment cycle. Dropping to 68 kg was quick: a kilo each "fast" but then dropping down below my setpoint is harder, slower, and I tend to jump up a kilo if I eat a tiny slice of Christmas cake or eat one chocolate when I am not fasting.
I am determined to get there, and it is much easier once chemo is over.
good luck and best wishes