Smart answer:

Your search for What is a mastectomy returned the following results:

surgical partial or complete removal of one or both breasts in individuals with breast cancer

Mastectomy is surgical partial or complete removal of one or both breasts in individuals with breast cancer.

surgery to remove the whole breast

Mastectomy is surgery to remove the whole breast and may be the best option depending on the type of cancer.

to remove one or both breasts

Mastectomy is surgery to remove one or both breasts.

Source:

surgery to remove a breast, usually to treat or help prevent breast cancer

Mastectomy is surgery to remove a breast, usually to treat or help prevent breast cancer.

surgical procedure in which malignant tissue in the breast and surrounding structures is removed

A mastectomy is a surgical procedure in which malignant tissue in the breast and surrounding structures is removed.

the partial or complete removal of the breast

A mastectomy is the partial or complete removal of the breast.

Source:

surgery

Mastectomy is surgery to remove the entire breast along with other nearby tissue.

a complete removal of the breast

On the other side, mastectomy is complete removal of the breast and can be of many types depending upon the stage and characteristic of cancer.

Source: