A fistula is an abnormal opening between two parts of the body or a part of the body and the skin. It is a rare side effect of cancer treatment. Sometimes, they develop because of the cancer growing.

What is a fistula?

A fistula is an opening between areas of the body that are not usually connected. Sometimes this can be caused by cancer treatment. Less commonly, a fistula can be caused by cancer growing into an area of the body.

Fistulas caused by cancer are rare and can take many months or years to develop. They can develop in the pelvic area (lower tummy between your hips). For example, an opening may develop between:

  • the bladder or bowel and the vagina
  • the bowel and the bladder
  • the rectum and the bladder or urethra.

Less often, cancer or cancer treatment can cause a fistula in other parts of the body such as inside the chest. Or it can develop from inside the body going out through the skin.

A fistula can be difficult to cope with physically and emotionally. Your specialist nurse and doctor can support you. They can explain the best ways to treat or manage fistula symptoms.

Fistula in the male body
Image: Fistula in the male body


Fistula in the female body
Image: Fistula in the female body


Causes of a fistula

Certain risk factors may increase the chance of developing a fistula. But having some or all of these risk factors does not mean it will happen. Most people with cancer never develop a fistula.

The following factors may increase your risk of getting a fistula:

  • The cancer started in the pelvic area – for example, if you were diagnosed with cervical cancer or bowel cancer.
  • The cancer is large and grows quickly (high-grade cancer).
  • You have had surgery or radiotherapy, or both. Radiotherapy and chemotherapy together (chemoradiation) may also increase the risk.
  • You have long-term side effects after pelvic radiotherapy (sometimes called pelvic radiation disease).
  • You have had a biopsy (sample of tissue taken for testing) from an area where you previously had radiotherapy.
  • You have had previous treatment with some targeted therapy drugs, for example bevacizumab (Avastin®) and pazopanib (Votrient®).
  • You have other medical conditions such as colitis, Crohn’s disease or diverticulitis.

Fistula symptoms

The symptoms of a fistula depend on the parts of the body that are affected. In this information, we have listed the most common symptoms of some types of fistula.

Some of these symptoms can be caused by other conditions. But it is important to get them checked by your doctor.

Bladder fistula symptoms

Symptoms of a fistula between the bowel and bladder include:

  • pain when passing urine (peeing)
  • passing urine more often
  • bubbles in the urine
  • urine that is smelly and looks cloudy or muddy in colour
  • passing stools (poo) in urine.

Bowel fistula symptoms

If a fistula is between the bowel and ureter or between the bowel and bladder, you may have urine leaking from the back passage.

If it affects any part of the bowel, you may have diarrhoea. But this is a common symptom of many other conditions.

Vaginal fistula symptoms

If a fistula is between the ureter and vagina or between the bladder and vagina, you may have urine leaking through the vagina.

If a fistula joins the vagina and bowel, you may have the following symptoms:

  • vaginal discharge that smells unpleasant
  • passing wind and stools (poo) through the vagina
  • redness and soreness of the vagina (vaginitis)
  • redness and soreness of the skin around the area.

Chest fistula symptoms

If a fistula joins the gullet (oesophagus) and the windpipe (trachea) or airways, you may have the following symptoms:

  • coughing after eating or drinking
  • feeling short of breath
  • having chest infections.

Diagnosing a fistula

A fistula can be caused by cancer treatment or the cancer itself. The doctor needs to know the cause to decide on the treatment.

Your doctor will ask about any cancer treatment you have had and about your symptoms. Depending on your symptoms, you may have some tests. If you have questions or worries about having an internal examination, tell the nurse or doctor. They can answer any questions you have and explain ways they can make it easier for you.

You may have some of the following tests:

Methylene blue test

This is used to help diagnose a fistula between the vagina and bowel. A tampon is placed into the vagina and then some blue dye (methylene) is placed into the back passage. The tampon is removed after about 10 to 15 minutes. Blue staining on the tampon means there is a fistula.

CT scan

CT scan takes a series of x-rays that create a 3D picture of the inside of your body. It can be used to find a fistula.

Before the scan, you may be given a special dye (contrast) which can help show a fistula more clearly on the images.

MRI scan

An MRI scan  is similar to a CT scan, but uses magnetism instead of x-rays to create a detailed picture of an area of your body. Before the scan, you may be given an injection of dye (contrast) into your vein. This can help things show up more clearly on the images.

Contrast x-rays

These are x-rays that use special liquid dye called contrast. Contrast can help the doctor to see things more clearly on an x-ray image. This can be helpful in finding a fistula because the contrast will move into the opening. Contrast x-rays have different names depending on the part of the body. They include:

  • Cystogram

    For this x-ray, contrast is given into the bladder through a catheter (a long, thin, flexible tube).

  • Vaginogram

    For this x-ray, contrast is given into the vagina through a catheter.

  • Fistulogram

    For this x-ray, contrast is given through a small catheter or blunt needle into an opening in the skin to see where it goes.

  • Intravenous urogram (IVU/IVP)

    For this x-ray, contrast is injected into a vein, usually in your arm, and flows through your bloodstream to your kidneys. The doctor can watch the flow of the dye on an x-ray screen and see any abnormalities in the kidneys, the bladder and the rest of your urinary system. The contrast may make you feel hot and flushed for a few minutes, but this feeling gradually disappears. You may feel some discomfort in your tummy (abdomen), but this will only be for a short time. You should be able to go home as soon as the test is over. 

Examination under anaesthetic

This allows your doctor to carefully examine the areas affected by the fistula while you are under a general anaesthetic. The doctor can do a thorough examination without causing you any discomfort.

Treating a cancer fistula

The treatment you have for the fistula often depends on what caused it and how well you are. If the tissues around the fistula are healthy, it may be possible to have surgery to close the fistula.

If the fistula is caused by the cancer coming back, it may not be possible to have surgery. You may have other treatments, such as chemotherapy to shrink the cancer. Your doctor and nurse specialist will talk to you about treatments to help manage the symptoms.

Sometimes a fistula will close without surgery or other cancer treatments. While it is healing, it can be managed with treatment to control symptoms.

You may see different doctors. For example:

  • If the fistula affects your bowel, bladder or vagina

    You may see:

    • a gastroenterologist – a doctor who treats problems with the digestive system
    • a colorectal surgeon – a doctor who does operations (surgery) on the large bowel
    • a urologist – a doctor who treats problems with the kidneys, bladder and male reproductive system
    • a gynaecologist – a doctor who treats problems with the female reproductive system.
  • If the fistula affects your skin

    You may see a plastic surgeon – a doctor who does operations (surgery) to repair or reconstruct tissue and skin.

  • If the fistula affects your chest

    You may see a thoracic surgeon – a doctor who does operations on the chest.

Fistulas can take weeks or months to heal. Unfortunately, some fistulas may never heal. But it is often possible to control the symptoms successfully. Your doctor or specialist nurse can discuss treatment options with you. If you are worried about your symptoms at any time, contact your doctor or specialist nurse for advice.

Fistula surgery

Surgery may only be possible if the tissue in the area around the fistula is healthy. Previous radiotherapy treatment to the area or scarring from previous surgery can affect the healing. In these situations, it may take longer to heal and sometimes it may not heal.

The type of operation depends on the areas of your body affected. You can discuss what the surgery will involve with your team of specialists. They can explain how the operation will affect you and the possible risks.

Often the surgeon will use your own body tissue to repair the fistula.

Surgery to create a stoma

If the fistula involves part of the bowel, you may need an operation to bring an opening of the bowel onto the skin of the tummy (abdomen). This is called a stoma. The stoma is called:

  • a colostomy if it uses part of the colon
  • an ileostomy if it uses the small bowel.

A bag is worn over the stoma to collect bowel movements.

The stoma will be either temporary or permanent. You may have a temporary stoma to rest the bowel. This allows symptoms, such as infection and inflammation, to improve before an operation to repair the fistula. It can also allow the area to heal after surgery. Or, you may have a stoma to help control your symptoms.

Your surgeon and specialist nurse will talk to you about having a stoma if they think it would help.

If the fistula involves the urinary system, you may need a stoma to pass urine. This is called a urostomy. The urostomy may be temporary or permanent.


A small tube called a stent can be used to seal a fistula between the windpipe (trachea) and the gullet (oesophagus). You usually have a stent put in under a general anaesthetic. It can be placed in the gullet or in the windpipe, or sometimes in both.

The doctor places the stent using a scope, which is a thin, flexible tube with a light and camera at the end. They place the stent inside the gullet using an endoscope, or inside the windpipe using a bronchoscope.

The stent is folded flat when it is first inserted. As it comes out of the scope, it opens up like an umbrella. It pushes against the wall of the gullet or windpipe, sealing the hole from the fistula. The stent can stay in permanently.

Cancer treatments

If the fistula has developed because the cancer is growing, you may have treatment to shrink the cancer. This may help the fistula to close. Treatment depends on the type of cancer and where the fistula is. You may have chemotherapy or radiotherapy.

Coping with the symptoms of a cancer fistula

You may have different treatments to help control the symptoms. It is important to tell your nurse or doctor how the fistula is affecting you. They can give you advice on the best way to manage your symptoms.

Sore skin

Your skin may become sore and red, and can sometimes become infected and ulcerated. Tell your doctor or nurse if your skin is broken or sore. They can prescribe painkillers and anaesthetic creams that can help. Using barrier films or creams that cover the area can help reduce symptoms. If your skin becomes infected, your doctor will prescribe antibiotics, either as tablets or as a cream.

After washing, pat the area dry with a clean, soft towel. Do not rub the area. If this is too painful, try using a cool hairdryer or an electric fan to dry the area.

We have more information about skin and nail changes from cancer treatment.

Unpleasant smell

Sometimes a fistula can smell unpleasant. Many people find this symptom the most distressing. Your nurse may use different dressings to help control an unpleasant smell. Some contain silver, which can reduce bacteria in the wound and control the smell. Charcoal dressings can also help filter any smell.

If the fistula is infected, antibiotics can help. Antibiotic gels can also be applied directly onto the area. Your doctor or nurse can tell you more about this.

You may feel self-conscious about an unpleasant smell, particularly when you are with other people. Air fresheners, environmental air filters and aromatherapy oils may disguise unpleasant smells and can help you feel more comfortable.

Leakage from the fistula

If the fistula opens on to your skin, fluid may leak out. Your nurse will give you advice about dressings you can use to cover the fistula. There are dressings that can absorb the leakage and help you feel more comfortable.

If there is a large amount of leakage, they may suggest using a drainage bag. The bag is stuck over the area where the fistula opens onto the skin.

Your doctor, specialist nurse or community nurse can advise you on the best way to manage any leakage. You or your carers can be taught how to change the dressings or manage the drainage bag. If you are at home and need help with this, a district nurse can visit you and provide support.

Leakage from the bladder or bowel

Having problems with leakage of urine or stool can be distressing and embarrassing. Your nurse can give you advice about pads and aids. These can help you feel more confident and protect your clothes.

You can ask to be referred to a continence adviser or a stoma nurse. The Bladder and Bowel Community may also be able to help.

If you need to go to the toilet more often, you can get a card to show to staff in shops, restaurants and pubs. This will usually allow you to use their toilets, without awkward questions. Macmillan has a free toilet card. You can also get a similar free Just Can’t Wait toilet card from the Bladder and Bowel Community.

Losing fluid

If a fistula is affecting the bowel, especially the small bowel, you may lose a lot of fluid. This can cause dehydration and affect the balance of nutrients in your body.

Try to drink plenty of liquids. Your cancer doctor or nurse can tell you how much you should drink each day. Sometimes you may be given fluids by a drip (infusion) into a vein (intravenously).

Drugs such as octreotide slow down the amount of fluid that is lost. Octreotide is given by injection under the skin (subcutaneously) or into a vein (intravenously).

Other medicines such as loperamide and codeine phosphate can slow down the bowel and reduce the amount of fluid lost.


If you are losing a lot of fluid from the bowel, especially the small bowel, you may not be getting enough nutrients to keep your body healthy. A dietitian can give you advice about the best way to stay well-nourished, while slowing down the amount of leakage.

Your dietitian can advise you if a low-fibre diet would be helpful.

If you are not getting enough nutrients and are losing weight, you may have fluids containing nutrients through a drip into a vein. This is called parenteral nutrition.

Your feelings about having a fistula

You may feel anxious, embarrassed or depressed because of your fistula. Or you may feel isolated and worry about going out. The fistula may affect how you see, feel and think about your body (body image). You will probably be much more aware of the fistula than other people. Talking to family or friends often helps.

You may also find it helpful to talk to your doctor or nurse about how you are feeling. They can refer you to local counselling services. Support groups and complementary therapies, such as relaxation and aromatherapy, can also be helpful. We have more information about talking, counselling and support groups.

If the fistula is affecting your relationships, organisations such as the College of Sexual and Relationship Therapists may be also able to help.

Our cancer support specialists can give you details of support organisations and counselling services in your area. You can call the Macmillan Support Line on 0808 808 00 00 7 days a week, 8am-8pm. It may also help to share your experience with other people through Macmillan’s Online Community.

About our information

  • References

    Below is a sample of the sources used in our fistula information. If you would like more information about the sources we use, please contact us at

    Golabek T, Szymanska A, Szopinski T, et al. Enterovesical fistulae: aetiology, imaging, and management. Gastroenterol Res Pract, 2013, 617967. doi:10.1155/2013/617967

    UpToDate. Colovesical fistulas. [Internet], 2021. Available from [accessed January 2021].

    UpToDate. Tracheo- and broncho-esophageal fistulas in adults. [Internet], 2020. Available from [accessed January 2021].

    UpToDate. Urogenital tract fistulas in women, 2021. Available from [accessed January 2021].

  • Reviewers

    This information has been written, revised and edited by Macmillan Cancer Support’s Cancer Information Development team. It has been reviewed by expert medical and health professionals and people living with cancer. It has been approved by Chief Medical Editor, Professor Tim Iveson, Consultant Medical Oncologist.

    Our cancer information has been awarded the PIF TICK. Created by the Patient Information Forum, this quality mark shows we meet PIF’s 10 criteria for trustworthy health information.

Date reviewed

Reviewed: 01 July 2021
Next review: 01 July 2024
Trusted Information Creator - Patient Information Forum
Trusted Information Creator - Patient Information Forum

Our cancer information meets the PIF TICK quality mark.

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