Transanal endoscopic microsurgery (TEM) is a procedure to treat rectal tumors and other problems without making any incisions. Instead, your surgeon inserts microsurgical tools through your anus. TEM has a lower risk of complications and is less painful than open surgery.
Transanal endoscopic microsurgery (TEM) is a procedure to treat rectal problems like tumors. Your surgeon inserts small tools through your anus (butthole) to reach your rectum (the lower part of your large intestine). There are no surgical incisions, so you recover quicker and with less pain than in open surgeries.
TEM allows your surgeon to reach rectal tumors high in your rectum. In the past, surgeons could only reach these tumors with open abdominal surgery. Open abdominal surgeries use a large belly incision and can cause long, painful recoveries.
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In TEM surgery, your provider inserts a rigid instrument called a rectoscope into your anus. Then they pass small instruments and a camera through the rectoscope.
In transanal minimally invasive surgery (TAMIS), your surgeon inserts a small, gel-like, round port into your anus. They place a small camera and surgical tools through the port. In TAMIS, the camera and tools are the same ones they use during laparoscopic surgeries.
Transanal endoscopic microsurgery may be a good option if you have multiple health conditions or can’t tolerate open surgery. TEM offers a way to remove colorectal cancer without performing open abdominal surgery. TEM is also a useful tool for younger people with early stage or benign (noncancerous) rectal tumors.
Not everyone is a candidate for TEM. Because the rectoscope is so rigid, your backbone could block your surgeon’s path to the tumor. In these cases, you may need TAMIS, which uses more flexible tools. People who have a narrowing or stenosis of the anal canal may not be a candidate for TEM or TAMIS.
Most often, your surgeon uses TEM to remove growths or tumors in your rectum. You may have transanal endoscopic microsurgery to treat:
Preparing for TEM is similar to preparing for a colonoscopy. You need to poop and empty your bowels completely so that your surgeon has a clear view of your rectum. You typically take a laxative to clear your colon and electrolytes to prevent dehydration.
Your healthcare provider will likely instruct you to:
Plan to stay home during your bowel prep. Your provider may also instruct you to stop taking certain medications, such as blood thinners, for several days before the procedure.
You receive general anesthesia so that you stay in a sleeplike state during TEM. In transanal endoscopic microsurgery, your surgeon:
You may feel some discomfort immediately after the procedure. In the first 24 hours after surgery, you may have a:
You can begin eating and drinking within a day after surgery. You may stay in the hospital for one to two days after transanal endoscopic microsurgery.
Transanal endoscopic microsurgery allows colorectal surgeons to reach higher parts of your rectum without making an abdominal incision. In the past, these tumors required extensive abdominal surgery. These invasive procedures can have long-term side effects, including bladder problems, erectile dysfunction and permanent colostomy.
In contrast, TEM is typically painless and offers multiple benefits, like:
Transanal endoscopic microsurgery has lower complication rates than open abdominal surgery. However, there’s a small risk of:
You can get up and move around on the same day as your procedure. After you return home, you can resume your usual activities as you feel able, usually within a day or two.
You may have liquid bowel movements for several weeks after TEM. If needed, you may work with a nutritionist or dietitian to adjust your diet until your bowel function returns to normal.
Your healthcare provider may recommend TEM for early-stage rectal cancer. For many people, the procedure successfully removes the tumor, and you don’t need any other treatments. However, some people also need other cancer treatments, such as chemotherapy or radiation therapy, in addition to TEM.
A note from Cleveland Clinic
Finding out you have a tumor can be scary. You may start thinking about the pain and long recovery associated with surgery. With transanal endoscopic microsurgery, your surgeon can remove rectal tumors without making any incisions, so you recover quicker and with less pain. Instead of making a long abdominal incision, your surgeon inserts special instruments through your anus. TEM is a safe, minimally invasive procedure with low complication rates.
Last reviewed by a Cleveland Clinic medical professional on 05/03/2023.
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