Yes, breast cancer can look like a pimple or even a boil. These are unusual and late presentations of breast cancer, but certainly can happen. Usually, if a boil turns out to be breast cancer, there is a long standing history of a growing lump in the breast before the boil breaks open. If a boil turns out to be breast cancer, it will not get better with things like antibiotic ointment or other topical/ skin preparations.