All types of surgery have the following potential complications:
Adverse reaction to general anesthesia. Serious consequences of this complication are very rare (e.g., 1 death in 200,000 surgeries).
The potential main complications that are specifically associated with a mastectomy surgery include:
Tenderness of the area next to the incision, because several nerves were cut during the surgery. Usually, the tenderness subsides as the nerves grow back.
Skin numbness along the incision site, because several nerves were cut during the surgery.
Collection of fluid under the scar. The collection of fluid may be one of two types: hematoma or seroma. A hematoma is an accumulation of blood in the wound. A seroma is an accumulation of clear fluid in the wound. If collection of fluid under the scar has occurred, your surgeon may need to remove the fluid with a needle and syringe.
Delayed healing of the wound. During mastectomy, the blood vessels that supply your breast tissue are cut, which can make it harder for your body to heal at the incision site. Rarely, there may not be enough blood flow to the flaps of an incision, which can cause small areas of skin to wither and scab. In certain instances, your surgeon may need to trim these scabs on the skin.