has she got any other symptoms?
"The signs and symptoms of breast cancer include, a lump or thickening in the breast or armpit area, changes in the appearance and texture of the skin, for example, redness or dimpling, noticeable changes in the nipple, for example, changes in the position or direction, a rash or discharge, change in the shape or size of the breast that may indicate the presence of a lump, and also any pain or discomfort that is unusual or new. However, pain alone without any of the other symptoms isn’t likely to be due to breast cancer," (CancerHelp UK, 2002).
she should go to her doctor as soon as possible.
afaik, she may be refferred for a mammography. the breast unit where they do them at my local hospital is like a one-stop shop, so you get your mammography & results/diagnosis on the same day, so i should imagine that's the same everywhere.
hope that helps?