Weight lose after cancer

I am hoping to find someone with a success story on losing weight post cancer treatment. I am back at trying to lose weight again since chemotherapy for the third time. I am about 6 weeks in and so far no results. (Yes, I eat healthy. I have a 95% plant based diet and calorie count.)

My oncologist says most women can't lose weight after treatment but I don't want to believe that! Any motivational stories would be greatly appreciated!

Thank you and have a blessed day.