There are many options for breast reconstruction after mastectomy (removal of breast for breast cancer). The simplest reconstruction involves a prosthesis implant. Most commonly this means a silicone, or saline filled breast implant that is identical to the implants that are done for breast enlargement for cosmetic reasons. Another option is a flap. There are several types of flaps. First it helps to provide a definition of "flap." A flap generally refers to a piece of tissue that is taken from one part of your body and relocated to another part of your body.
The key to flap survival is to have adequate blood supply to keep the flap viable (living). So blood vessel re-connection is critical to success of a flap. The most common flap is the "TRAM" flap which stands for "Transverse Rectus Abdominis Myocutaneous" flap. What this involves is taking out the skin, fat and one column of your rectus abdominis muscle (also known as the midline abdominal muscle that make up the "six pack") and moving it to the right or left breast. The flap survives, because it keeps the same blood supply from the superior epigastric blood vessels. The downside to this flap is that it creates a weakness in the area where the muscle is removed, making the patient slightly more prone to developing an abdominal wall hernia
A newer flap is the "DIEP" flap, which stands for "Deep Inferior Epigastric Perforator" flap. The advantage of this flap is that it leaves the muscles and only takes the skin and fat layers of the lower belly, leaving the muscles in place which reduces the likelihood of developing a hernia. This piece of skin and fat tissue is then used to sculpt a new breast - which in theory should replicate the most natural feel of the new breast because it is essentially the same consistency (i.e. skin and fat tissue). The name of the flap is derived from the blood vessels that supply this piece of tissue. The deep inferior epigastric vessels are dissected out and are left attached to the translocated skin/fat. They are then reconnected to blood vessels in your chest using a microscope to aid in the connection (that is why its considered "Microsurgery
In simple terms, an oval piece of skin and fat is taken out from your lower belly (most of it from under the belly button). Part of this island of skin and fat that is taken out are the blood vessels (Deep Inferior Epigastric Perforators) that naturally feed blood to this part of the skin and fat. They are then connected to blood vessels in the chest to make sure this tissue remains viable (living) and the skin and fat are sculpted to form the new breast. The fat makes up the breast mound and the skin over it is connected to the leftover skin on the breast.
In terms of looks, either implants or flaps would work well. The main advantage of flaps is that they tend to feel more natural as the breast tissue (which is mostly fat) is replaced with the similar tissue (fat from your belly). On the other hand, implants give you more options if you want to increase your cup size. (you would obviously need one implant in each breast to match them).
A few things to note:
-In most breast reconstruction, if the nipple has to be excised (cut out) as part of the mastectomy (breast removal), the nipple is usually reconstructed at a later time.
-Patients sometimes prefer the flap reconstruction (TRAM or DIEP) because it feels the most natural, and because there is an added advantage of a "tummy tuck" which is part of the operation.
I hope this description answers your question. As always, the best thing to do is to speak to your breast and/or plastic surgeon
for a better explanation of all of your reconstructive options.