Surgery for Rectal Cancer:
Surgery is usually the main treatment for rectal cancer. Radiation and chemotherapy are often given before or after surgery. The type of surgery used depends on the stage (extent) of the cancer, where it is, and the goal of the surgery.
A key piece of information needed before surgery is how close the tumor is to the anus. This can impact the type of surgery done. It can also impact outcomes if the cancer has spread to the ring-like sphincter muscles around the anus that keep stool from coming out until they relax during a bowel movement.
Polypectomy and local excision
Some early rectal cancers and most polyps can be removed during a colonoscopy. This is a procedure that uses a long flexible tube with a small video camera on the end that’s put into the person’s anus and threaded into the rectum. These surgeries can be done during a colonoscopy:
- For a polypectomy, the cancer is removed as part of the polyp, which is cut at its stalk (the part that looks like the stem of a mushroom). This is usually done by passing a wire loop through the colonoscope to cut the polyp from the wall of the rectum with an electric current.
- A local excision is a slightly more involved procedure. Tools are used through the colonoscope to remove small cancers on the inside lining of the rectum along with a small amount of surrounding healthy tissue on the wall of rectum.
When cancer or polyps are taken out this way, the doctor doesn’t have to cut into the abdomen (belly).
Local transanal resection (full thickness resection)
This procedure can be used to remove some early stage I rectal cancers that are relatively small and not too far from the anus. As with polypectomy and local excision, local transanal resection (also known as transanal excision) is done with instruments that are put into the rectum through the anus. The skin over the abdomen (belly) isn’t cut. This procedure can be used to remove some early stage I rectal cancers that are relatively small and not too far from the anus. It’s usually done with local anesthesia (numbing medicine) – the patient is not asleep during the operation.
In this operation, the surgeon cuts through all layers of the rectal wall to take out the cancer as well as some surrounding normal rectal tissue. The hole in the rectal wall is then closed.
Lymph nodes are not removed during this procedure, so if the tumor has grown deep into the rectum, radiation with or without chemotherapy may be recommended after surgery.
Transanal endoscopic microsurgery (TEM)
This operation can sometimes be used for early stage I cancers that are higher in the rectum and can’t be reached using the standard transanal resection (see above). A specially designed magnifying scope is put through the anus and into the rectum. This allows the surgeon to do a transanal resection with great precision and accuracy. This operation requires special equipment and surgeons with special training and experience, so it’s only done at certain cancer centers.
Low anterior resection (LAR)
Some stage I rectal cancers and most stage II or III cancers in the upper part of the rectum (close to where it connects with the colon) can be removed by low anterior resection (LAR). In this operation, the part of the rectum containing the tumor is removed. The colon is then attached to the remaining part of the rectum (either right away or sometime later) so that the patient moves their bowels in the usual way.
A low anterior resection is done with general anesthesia, the patient is put into a deep sleep and doesn’t feel pain. The surgeon makes several small incisions (cuts) in the abdomen. The cancer and a margin (edge or rim) of normal tissue around the cancer is removed, along with nearby lymph nodes and other tissues around the rectum.
The colon is then reattached to the remaining rectum so that a permanent colostomy is not needed. (A colostomy is needed when, instead of reconnecting the colon and rectum, the top end of the colon is attached to an opening made in the skin of the abdomen. Stool then comes out this opening.)
If radiation and chemotherapy have been given before surgery, it’s common for a short-term ileostomy to be made. (This is where the end of the ileum, the last part of the small intestine, is connected to a hole in the skin of the abdomen.) This gives the rectum time to heal before body waste moves through it again. In most cases, the ileostomy can be reversed (the intestines are reconnected) about 8 weeks later.
Most patients spend several days in the hospital after a low anterior resection, depending on how the surgery was done and their overall health. It could take 3 to 6 weeks to recover at home. Watch video
Proctectomy with colo-anal anastomosis
Some stage I and most stage II and III rectal cancers in the middle and lower third of the rectum require removing the entire rectum (called a proctectomy). The rectum has to be removed so that a total mesorectal excision (TME) can be done to remove all of the lymph nodes near the rectum. The colon is then connected to the anus (called a colo-anal anastomosis) so that the patient will move their bowels in the usual way.
Sometimes when a colo-anal anastomosis is done, a small pouch is made by doubling back a short piece of colon (called colonic J-pouch) or by enlarging a segment of the colon (called coloplasty). This small reservoir or pouch of colon becomes a storage space for stool, like the rectum did before surgery. When special techniques are needed to avoid a permanent colostomy, the patient may need a short-term ileostomy (where the end of the ileum, the last part of the small intestine, is connected to a hole in the abdominal skin) for about 8 weeks while the bowel heals. A second operation is then done to reconnect the intestines and close the ileostomy opening.
General anesthesia is used (drugs are used to put the patient into a deep sleep) for this operation. Most patients spend several days in the hospital after surgery, depending on how it was done and their overall health. It could take 3 to 6 weeks to recover at home.
Abdominoperineal resection (APR)
This operation is more involved than a low anterior resection. It can be used to treat some stage I cancers and many stage II or III cancers in the lower part of the rectum (the part close to the anus). It’s often needed if the cancer is growing into the sphincter muscle (the muscle that keeps the anus closed and prevents stool leakage) or the nearby muscles that help control urine flow (called levator muscles).
Here, the surgeon makes a cut or incision (or several small incisions) in the skin of the abdomen, and another in the skin around the anus. This allows the surgeon to remove the rectum, the anus, and the tissues around it, including the sphincter muscle. Because the anus is removed, a permanent colostomy is created (the end of the colon is connected to a hole in the skin over the abdomen) to allow stool to leave the body.
General anesthesia (where the patient is put into a deep sleep) is used for this operation. Most people spend several days in the hospital after an APR, depending on how the surgery is done and their overall health. Recovery time at home may be 3 to 6 weeks.
If the rectal cancer is growing into nearby organs, a pelvic exenteration may be recommended. This is major operation. The surgeon will remove the rectum as well as any nearby organs that the cancer has reached, such as the bladder, prostate (in men), or uterus (in women).
A colostomy is needed after pelvic exenteration. If the bladder is removed, a urostomy is needed, too. (This is an opening in skin of the abdomen where urine leaves the body and is held in a pouch that sticks to the skin.) It can take many months to fully recover from this complicated surgery.
Some patients have rectal cancers that have spread and also have tumors blocking the rectum. In this case, surgery may be done to relieve the blockage without removing the part of the rectum containing the cancer. Instead, the colon is cut above the tumor and attached to a stoma (an opening in the skin of the abdomen) to allow stool to come out. This is called a diverting colostomy. It can often help the patient recover enough to start other treatments (such as chemotherapy).
Surgery for rectal cancer spread
If the cancer has spread to just one or a few spots in the lungs or liver (and nowhere else), surgery may be used to remove it. In most cases, this is only done if the main cancer in the rectum is also being removed (or was already removed). Depending on the extent of the disease, this might help the patient live longer, or it could even cure the cancer. Deciding if surgery is an option to remove areas of cancer spread depends on their size, number, and location.