Transanal Endoscopic Microsurgery (TEM)

Transanal endoscopic microsurgery (TEM) removes noncancerous tumours and early-stage small cancers from the rectum using microsurgical instruments through the anus.

The rectum is a 6-inch long end part of the large intestine that ends in the anus. The rectum stores stools received from the large intestine until they are excreted through the anus. Before the introduction of TEM, noncancerous tumours in the rectum were treated (removed) by burning, scraping, or major abdominal surgery. Major abdominal surgery to remove large and difficult rectal tumours included making a large abdominal incision (cut), removal of the rectum, and prolonged hospital stay and recovery period. A TEM is an excellent alternative to the traditional major surgery due to the following advantages:

• No need for surgical incision
• Minimal postoperative pain
• Shorter hospital stay
• Minimal bleeding
• Minimal risk of postoperative complications, including infections and bowel obstructions

The surgery involves the use of a specially designed microscope inserted through the anus. This helps the surgeon to look for small cancers or noncancerous growths in the rectum. Subsequently, small surgical instruments are passed through the microscope to remove them.

The surgery is usually recommended to remove lesions such as the following from the rectum:

• Noncancerous polyps (abnormal growths) 
• Early-stage small cancer
• Rectal fistulas

Some common symptoms of both the abovementioned conditions include:

• Abdominal pain
• Blood in stool
• Changes in bowel habits
• Nausea or vomiting

The surgeon will perform a TEM if early cancers or polyps are not removed during colonoscopy (a procedure that involves the use of a long, flexible instrument to look at and remove abnormal growths in the rectum).

A surgeon may not perform this procedure in individuals with:

• Cancer that has spread to lymph nodes
• Ulcerated tumour
• Poorly differentiated tumour
• Distant metastasis (spread of cancer cells to distant tissues)
• Invasion of the tumour cells in the blood vessels and lymphatics
• Large tumours that extend into the thick muscular layer of the rectum

You will have to visit the surgeon two weeks before the surgery for a preoperative assessment. Your surgeon will order several medical and imaging tests to confirm the diagnosis and ensure that you are eligible for the surgery. These include:

• Blood tests
• Urine tests
• Pregnancy test
• X-ray
• An electrocardiogram or ECG
• Colonoscopy

You will have to share the following details with the surgeon during the assessment:

• Current or previous medical conditions
• Allergies
• History of reaction to anaesthesia
• Whether you are pregnant
• A list of medicines that you take, including herbs and over-the-counter medications

Additionally, you will be provided with the following instructions to prepare for the surgery:

• Discontinue blood-thinning medicines like aspirin, warfarin, or ibuprofen. The surgeon will inform you about the medicines that you can take on the day of the surgery.
• Inform the surgeon if you have flu, cold, or fever on the days leading to the surgery. In such a case, your surgery may be postponed.
• Fast from the midnight prior to the surgery to prevent vomiting (risk of general anaesthesia) during the surgery.
• Quit smoking, if you do. This will help reduce the risk of complications associated with the surgery.
• Take a shower before you arrive at the hospital on the scheduled day of the procedure to minimise the risk of infections during surgery. In addition, remove all nail polish, body piercings, and make-up.
• Arrange for a friend, family member, or responsible adult to drive you home after discharge from the hospital.
• You will have to sign an approval form if you agree to the surgery.

After your admission to the hospital, the hospital staff will ask you to:

• Wear a hospital gown.
• Remove dentures and hearing aids if you wear one.
• Wear a pair of stockings in your legs to prevent the formation of blood clots.
• Use one to two enemas to empty your bowel. Another alternative to empty the bowel is a special fluid preparation that you may be asked to take on the night before the surgery

When the time comes for the surgery, your body temperature will be measured and, subsequently, you will be taken to the operation theatre. Right before the procedure begins, you can expect the following:

• An oxygen mask will be used to help you breathe during the surgery.
• Your vital signs (heart rate, blood pressure, pulse, and blood oxygen level) will be measured.
• An anaesthetist will administer general anaesthesia to you to make you fall asleep.
• An intravenous (IV) line will be inserted in your arm or hand to supply essential fluids and medicines throughout the procedure.

The procedure involves the following steps:

• The surgeon will insert a special microscope and surgical instruments through your anus into your rectum.
• Subsequently, he/she will inflate your rectum with gas to allow more area to operate.
• The surgeon will then use surgical instruments to grab and cut out small cancerous or abnormal growth in your rectum.
• The operated area may or may not be closed. If closed, absorbable stitches or metal clips will be used. They need not be removed.

During the surgery, the surgeon will also take out a cuff of healthy tissue surrounding the rectal polyp to ensure that there is no residual abnormal tissue. A tube will be inserted in the operated area (rectum) to drain excess fluids.

You will wake up in the recovery ward post-surgery where the medical team will monitor your vitals for a while and then move you to the regular ward. You may require a hospital stay of about one to two days, during which, you will be given fluids through an IV line till the time you can drink and eat again and you will have an oxygen mask to supply oxygen.

Although you may feel a little discomfort due to inflammation in the rectum, you will be able to walk soon after surgery.

On the next day of the surgery, the hospital staff will remove the drain tube and perform a blood test to check for signs of infection.

Once you reach home, you will need to take the following care:

• Use warm water to gently clean the back passage after each bowel movement during the initial few days after surgery.
• Take a sitz bath (sitting in warm water) for 10 to 20 minutes up to four times every day for a minimum of two days. This will help minimise any pain and discomfort you may experience.
• Avoid being constipated during the recovery period as excessive straining while passing stools can increase the risk of postoperative complications. The condition can be prevented by including fibre in your diet and drinking plenty of fluids. You can also include lactulose in your medicines to soften your stools.
• Avoid strenuous activities and lifting heavy objects for at least two weeks after the operation.
• Avoid sexual intercourse and inserting objects (including tampon) in the vagina or rectum for two weeks after TEM to prevent any injury to the operated area.
• There may be some faecal leakage due to stretching of anal muscles during the procedure. You can wear a pad for protection until the leakage stops.
• You will need to rest for one to two weeks before returning to work. 

When to see the doctor?

Contact the surgeon if you experience any of the following after the surgery:

• High body temperature
• Difficulty passing stools
• Foul-smelling discharge from the rectum
• Persistent nausea, vomiting or bleeding from the rectum
• Severe pain in the lower back, abdomen, or around the operated area
• Difficulty passing urine
• Pain that persists even after taking medicines

The potential complications/risks associated with the surgery include:

• Infection
• Bleeding
• Blood clots in the legs or lungs
• Slight leakage from the anus
• Hole in the rectum
• Inflammation of the pelvis
• Requirement of a major surgery

You will be required to revisit the surgeon six weeks after the operation to monitor the results of the surgery.

Disclaimer: The above information is provided purely from an educational point of view and is in no way a substitute for medical advice by a qualified doctor.