If it were me, I would try castor oil packs with good quality castor oil, and eat lots of raw garlic to kill infection. My dog had fatty tumors on his body, they were the size of butterscotch discs. I gave him garlic for parasites and they are gone now. It took a couple of weeks. Please don't be offended by the reference to my dog, I would think it would have the same effect on any mammal.
I tend to believe the theory that many cysts and tumors are caused by parasites, so a parasite cleanse may also help.
Losing weight will have many benefits to you, but I don't think it will make that growth go away by itself.