Childhood breast cancer typically appears in the form of fibroadenomas tumors, which are benign (not cancerous). These tumors rarely become cancerous. Symptoms may include: a lump or thickening in or near the breast or under the arm; a change in the size or shape of the breast; dimples on the breast; an inverted nipple; and scaly, red, or swollen skin on the breast or nipple. Physical exams and imaging tests such as MRIs, ultrasounds, and X-rays, can all be used to diagnose childhood breast cancer. Malignant (cancerous) tumors in children and young adults are often more difficult to treat than in adults. Treatment may not be required if the tumors are benign, but to remove the tumor, surgery or radiation therapy is typically used.