While keloids (large, painful scars that occur after surgical procedures, piercings, injury to skin etc) are generally of most concern to breastfeeding patients when they occur on the nipple, they also can be a pain and cosmetic concern elsewhere on the breast or chest wall.
This is an example of keloid formation in an Asian patient (patients with darker skin pigmentation tend to be more at risk for keloids) after an open heart surgery. We treated this with steroid injection into the keloid.