Transanal endoscopic microsurgery (TEMS)

TEMS is an operation, using a specially designed microscope and instruments, to allow surgery to be performed through the anus (back passage) inside the rectum. It requires no cuts on the outside of the anus or abdomen (tummy).

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What conditions is TEMS used for?

Most often it is used to remove benign polyps (non-cancerous growths) from the rectum that cannot be taken away other than by a major operation. Before TEMS; difficult and large, often flattened or ‘carpet-like’, polyps in the rectum required a major operation with removal of the rectum altogether or were incompletely treated by burning or scraping away.

Sometimes, TEMS is used to remove small cancers from the rectum and so avoiding major surgery. This can be done in very early cancers or considered where the TEMS operation is safer than major surgery. Where necessary, your surgeon will explain these choices to you.


Will I need any special preparation before the operation?

You will have investigations and tests to prepare you for your operation. These are to confirm the diagnosis, to see how far the disease has spread, and to assess how fit and well you are for the proposed treatment.

To perform the operation, the rectum needs to be completely empty. You may need to take oral bowel preparation the day before surgery or the back passage may be cleared out using an enema on the day of surgery. A specialist nurse will explain and ensure you are prescribed the preparation you require.


Will I need to have a stoma (bowel bag)?

Very rarely, if you need a stoma or it is possible that you may need a stoma, you will be seen by a stoma care nurse. These specialist nurses are skilled in caring for patients who have a stoma and will be able to answer any questions you may have.


What happens during the operation?

The operation on the rectum is performed through your anus. Using specially designed instruments and viewing the procedure through a microscope your surgeon will precisely cut out the polyp or small cancer ensuring that a cuff of normal surrounding lining is included in the portion of rectum removed. After this, your surgeon will decide if the space left behind needs to be closed by stitching the healthy edges of the rectal lining together or simply left open to heal naturally.


What should I expect after surgery?

You are likely to stay in hospital 1 or 2 days after the operation.

Immediately after the operation (within the first 24 hours), you will need:

  • Oxygen through a face mask
  • A drip into a vein in one of your arms to give you fluid
  • A catheter (tube) in your bladder to drain away urine
  • Sometimes a tube is left in the back passage for the first day to drain away any excess fluid
  • You may feel some discomfort, though rarely pain, in the back passage

Later, the same or following day you will be able to:

  • Eat again, starting with liquids and gradually introducing
  • Solid foods, and
  • Move around as soon as possible.
  • A temperature is common after the operation and you may be given
  • Oral antibiotics

When you first start going to the toilet again, your faeces (bowel movements) will be liquid. Sometimes it takes several weeks to get back to normal, and occasionally you may have to adjust your diet.


Are there complications with this operation?

Risks of this operation are small and much less than doing nothing. Also much less than the alternative of a major operation where less than 5% or fewer than 1 in 20 patients may not survive the surgery.
There are sometimes complications. These may include:

  • Bleeding
  • Infection
  • Inflammation of the pelvis: this may occur because the exposed operation site irritates the tissue around the rectum; antibiotic treatment may be necessary
  • Incontinence: you might experience staining of underwear or seepage for a few days after the operation because of the slight stretching of the anus required to insert the operating system; this usually returns to normal without the need for further treatment
  • Deep vein thrombosis (blood clots in the veins in the legs), or
  • Pulmonary emboli (blood clots in the lungs)
  • Major surgery: sometimes it is not possible to complete the operation by the TEMS procedure and so major surgery will be required; if this is a possibility it will be explained by your surgeon before the operation

If you have any new concerns, feel unwell or problems (for example, severe abdominal or back pain, a raised temperature or bleeding) after you leave hospital, it is important to contact your own doctor (GP) or the hospital. You will be given contact numbers for such an event.