One possibility is neurofibroma, which is usually part of systemic fibromatosis and can be removed by surgery.

Another possibility is breast lipoma, which is the most common benign tumor on the body surface. Most of them occur in obese female patients, and surgical resection is the main treatment.

Another possibility is soft fibroma, also known as skin tumor or fibroepithelial papilloma on areola, which needs to be examined in a hospital.