prophylactic mastectomy
Meaning of prophylactic mastectomy: Breast removal chosen before any cancer exists, lowering risk sharply while never quite reducing it to zero.
Definition of prophylactic mastectomy
A prophylactic mastectomy is surgical removal of a breast in someone who has no cancer in it, carried out to reduce the chance of one developing. It may involve both breasts in a person at high inherited risk, or the unaffected breast in someone already treated for cancer on the other side. A small amount of breast tissue always remains behind.
Who is it considered for?
| Situation | Why risk is raised |
|---|---|
| Inherited change in a breast cancer gene | Lifetime risk many times the average |
| Strong family pattern with no gene identified | Shared inheritance not yet traceable to a test |
| Radiation to the chest at a young age | Breast tissue exposed while still developing |
| Certain high-risk changes found on biopsy | A marker of raised risk across both breasts |
| Cancer already treated in the other breast | Concern about the breast that remains |
How much risk does it remove?
A great deal of it, though not all. Breast tissue reaches up toward the collarbone, outward into the armpit and down across the ribs, and no mastectomy can lift out every last cell of it without taking skin that has to be left in place. Cancer arising in what remains is uncommon, but it does occur, which is why risk-reducing mastectomy has largely replaced the older word in careful writing: prophylactic implies a guarantee the surgery cannot give. When both sides are removed the operation is recorded as a bilateral prophylactic mastectomy, and the reduction in risk for someone carrying a high-risk gene change is substantial.
What does it not do?
Removing the opposite breast after a diagnosis on one side lowers the chance of a new cancer forming there, and that much is well established. Whether it lengthens life is a separate question, and outside the group carrying a high-risk gene change it has not been shown to. The reason is that the outlook is governed mainly by the breast cancer already diagnosed rather than by a second one that might never appear. The surgery brings its own consequences as well, among them healing problems, permanent loss of sensation in the skin, and the effects on body image and on reconstruction, which is usually planned alongside it. Intensive screening and risk-reducing medication are the alternatives weighed against it.
Also known as
Used in a sentence
A prophylactic mastectomy was discussed once the gene test result was returned.
Good to know
Some breast tissue always remains after the operation, so risk is reduced rather than abolished, and outside the group carrying a high-risk gene change, removing the unaffected breast has not been shown to lengthen survival.
Word origin
Where “prophylactic mastectomy” comes from
Prophylactic comes from the Greek prophylaktikos, meaning guarding beforehand; mastectomy joins mastos, a breast, with ektome, a cutting out.