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About chemoradiotherapy for rectal cancer

Treatment with chemotherapy and radiotherapy together is called chemoradiotherapy. You might have this treatment for cancer of the back passage (rectal cancer). 

Chemotherapy uses anti cancer (cytotoxic) drugs to destroy cancer cells. The drugs circulate throughout the body in the bloodstream.

Radiotherapy uses high energy x-rays to destroy cancer cells.

Giving these treatments together before surgery can lower the chance of your cancer coming back nearby.

When do you have chemoradiotherapy?

You usually have chemoradiotherapy before surgery. Doctors also call this long course chemoradiotherapy.

You might have chemoradiotherapy before surgery if:

  • your rectal cancer has spread to nearby structures and tissues
  • it might be difficult for your surgeon to remove the rectal cancer with a clear border of tissue (margin)

What chemotherapy will I have?

The most common chemotherapy is fluorouracil (5FU), which you have through a drip. You usually have it in a chemotherapy day unit.

Or you might have a drug called capecitabine (Xeloda) as tablets. Capecitabine is similar to fluorouracil. You take it as tablets twice a day throughout your treatment.

You might have the chemotherapy before the radiotherapy starts. You continue to have it during the radiotherapy treatment.

Having fluorouracil

You might have fluorouracil in one or more of the following ways:

  • through a drip (an infusion)
  • as an infusion through a pump you wear 24 hours a day
  • as a series of injections into a vein before radiotherapy treatment

A nurse puts a small tube into one of your veins and connects it to the drip or you might need a central line. This is a long plastic tube that gives the drug into a large vein, either in your chest or in your arm. It stays in while you’re having treatment.

Taking capecitabine tablets

You must take tablets according to the instructions your doctor or pharmacist gives you.

Whether you have a full or empty stomach can affect how much of a drug gets into your bloodstream.

You should take the right dose, not more or less.

Never stop taking a cancer drug without talking to your specialist first.

Radiotherapy treatment

You have treatment in the hospital radiotherapy department.

Before you begin treatment, the radiotherapy team work out how much radiation you need. They divide it into a number of smaller treatments. They call each treatment a fraction. At your planning appointment the radiographers might make pen marks or small tattoos on your skin in the treatment area.

Your treatment starts a few days or up to 3 weeks after the planning session. You have radiotherapy from an external machine as a daily treatment, five days a week for around 5 weeks.

Side effects

Last reviewed: 
15 Oct 2018
  • Rectal Cancer: ESMO Clinical Practice Guidelines
    B. Glimelius and others
    Annals of Oncology 2013; 24 (Suppl 6): vi81-vi88