I Had a Mastectomy in January and I Getting 500cc High Profile Implants Soon. I Want my Cup Size to Full 34C?

It is hard to predict exact cup size.  Cup size varies a lot depending on different brand and style of bras you buy. With 500cc implant, you may become C or D. I usually tell patients not to worry too much about cc volume.  If you have expanders right now, you want to like the size that you have.  Ask your plastic surgeon how much of fluid volume you have in the expander and go slightly larger than that. Best wishes.

Whenever I perform a tissue expander to implant reconstruction, I always ask my patients to tell me as I am filling the expander up at what point they like the volume. It is usually that volume I choose for the final implant volume and match the shape for the patients chest.

It sounds like you have a tissue expander in place.  A 500 cc implant would most likely translate to about 2 cups sizes for you, possibly a small C cup for a reconstruction.