Breast leakage is not visible for a short period of time and breast fistula is old for a long period of time. When an abscess forms in the breast area as a result of milk stagnation during breastfeeding, the abscess needs to be surgically incised and an incision called a milk fistula will be formed. The patient usually presents with swelling in the areola area, and the abscess breaks down into the skin on one side and erodes into the milk ducts on the other, creating two open channels to the nipple. The granulation on the surface may appear to be healing, but it can also lead to the formation of leaky ducts, which can be difficult to treat. Leaky ducts occur when milk flows out of the healed wound after an abscess or benign tumor is removed during breastfeeding and the breast is accidentally damaged. If this condition is left untreated for a long time during breastfeeding, the wound will not heal for a long time. Since breast leakage is mainly localized inflammation, localized hyperplasia is less obvious after treatment. However, the surface of the fistula is old and leaves localized scarring, and a fistula can form, making treatment more difficult.