Will I be able to keep my nipples during a mastectomy?

May or may not. Most commonly a mastectomy for breast cancer includes removal of the nipple and areola. There is a type of mastectomy called nipple sparing mastectomy. This procedure may not be appropriate for cancer treatment in many situations. You need to talk to your breast surgeon to see if your condition is suitable for this procedure. Not all surgeons do this procedure.
It depends. When a mast-x is recommended to treat a breast cancer, this usually includes removal of the nipple-areolar complex. In recent years, studies have shown that select cancers can be treated by sparing the nipple and areola. Furthermore, when performing a mast-x to prevent cancer ("prophylactic mast-x"), the nipple-areolar complex is often spared, especially when combined with a reconstruction.