Skin flap necrosis and wound breakdown after mastectomy

During a mastectomy the breast tissue is lifted away from the skin, leaving thin layers of skin called flaps that are then closed over the chest or over a reconstruction. These flaps depend on a small blood supply that runs just under the surface. If part of a flap does not get enough blood, that skin can die, which is called skin flap necrosis. It usually shows up within the first few days to two weeks as skin near the scar edge turning dusky, purple or blue, then darker, and sometimes forming a black, dry crust. Wound breakdown means the scar edges come apart, which can happen on its own or after necrosis. Small areas along the edge are fairly common and often heal with dressings over a few weeks. Larger or full-thickness areas may need the dead skin trimmed away, sometimes in the operating theatre, and occasionally an implant or expander has to be removed if it becomes exposed or infected. Smoking, diabetes, higher body weight, large breasts, previous radiotherapy, very thin flaps and skin-sparing or nipple-sparing techniques with immediate reconstruction all raise the risk. Although it is distressing, the problem is usually manageable, it does not mean the cancer has returned, and most wounds do heal. The main practical concern is that it can delay chemotherapy or radiotherapy, so early reporting matters.

It is about blood supply

Skin that loses blood flow darkens and can die, usually near the scar edge.

Small areas often heal with dressings

Larger areas may need trimming or another operation.

Report changes early

Prompt care limits damage and helps keep further treatment on track.

Skin healing problems can be upsetting and slow, so it helps to know what to expect.

Healing can take weeks

An open wound healing from its base may need regular dressings for several weeks, sometimes longer.

Reconstruction can be affected

If an implant becomes exposed, it may need removing, with reconstruction tried again later.

The scar may look different

Areas that heal slowly often leave a wider or uneven scar, which can be revised later if needed.

What this page cannot tell you

It cannot judge how deep your skin change is. Only an examination by your team can do that.

Not every case can be prevented, but some steps clearly help.

Stop tobacco

Stopping smoking and chewing tobacco several weeks before and after surgery is one of the most helpful steps. Ask for support to quit.

Control blood sugar

Good diabetes control around the time of surgery supports healing.

Avoid pressure on the wound

Follow advice about bras and garments, and avoid tight straps pressing on flaps.

Report colour changes

Take a photo each day in good light if your team suggests it, so changes are easy to spot and share.