A: An inverted nipple can be corrected
The short answer to your question is yes. Nipple inversion can occur for several reasons after your lumpectomy. This includes the "inner" scarring that occurs that likely brough part of the nipple with it, causing an inversion. To fix this, it is important to figure out which parts of the breast caused this: loss of skin, skin contracture, fat necrosis, infection, radiation, etc. Once this has been evaluated, then the principle of treating any nipple inversion are used: release the scar, add more tissue, etc. Recurrence can be common, so it is best to see a plastic surgeon with significant experience in this area.