Desmoid-type fibromatosis (DF) is sometimes called Desmoid Tumour or aggressive fibromatosis. It is a rare type of benign (non-cancerous) tumour but patients are treated by sarcoma specialist oncologists who have the skills and experience to treat them. People with DF may have more than one tumour located in the same area of the body.

DF develops from fibroblasts. These are a type of cell that provide cell support to the body’s tissues. DF can occur anywhere in the body but it is mostly found in the arms, legs and abdomen (tummy). DF can affect anyone but it mostly affects young adults, especially women, between 30 and 40 years old.

In every million people, 5-6 could be expected to develop DF.

It is difficult to predict how DF will develop. Sometimes they can be slow growing and they have also been known to get smaller without any treatment.

There is a small number of people (5-10%) with DF who have a condition called familial adenomatous polyposis (FAP) and Gardner Syndrome. This is a rare condition that can run in families. People affected by FAP may be diagnosed with DF following routine tests and scans to investigate the progression of their condition, such as a colonoscopy. Usually their DF will be in the abdomen and treatment will be different to those who do not have FAP. You can find out more about this in the global consensus paper linked here.

Signs and symptoms

People with DF that is not related to having FAP may discover a lump and visit their GP who will refer them to a specialist doctor. A specialist will do:

• A clinical examination – looking at and feeling the lump
• A scan – taking pictures of the inside of the body using ultrasound, CT or MRI
• A core needle biopsy – taking or testing a tissue sample. Core needle biopsies use a core (meaning hollow) needle to remove the tissue. This is usually done under local anaesthetic

A biopsy of DF should be done by a specialist sarcoma team who has expertise in diagnosing and treating DF. A diagnosis of DF should be confirmed by a specialist soft tissue pathologist.

Types of diagnostic scans


Uses x-radiation to take images of dense tissues inside the body such as bones or tumours.


A scan that uses soundwaves to create images from within the body.


The Computer Tomography (CT) scan takes a number of x-rays to make a 3D images of an affected area.


This test uses a thin, flexible tube called a colonoscope to look inside the colon.


Magnetic Resonance Imaging (MRI) uses magnets to create an image of the tissues inside the body. This is the most common scan used to diagnose DF.


Examination of a tissue sample by a pathologist under a microscope to identify disease. The tissue sample can be taken during a biopsy or from a tumour removed during surgery. A diagnosis of DF should be confirmed by a specialist soft tissue pathologist. 85–90% of DF tumours have mutations that are only found in DF. An investigation called mutational analysis looks for these mutations in DF tumours. This can help to accurately identify a DF tumour.


Who will treat me?

DF patients are treated under an oncology team. Oncology is the branch of medicine that treats cancer. DF is not a cancer but oncologists (doctors who specialise in the treatment of cancer) have the experience and skills to look after DF patients. Your treatment plan will need to be managed by a team of experts from a wide range of health care professions called a multidisciplinary team (MDT). The Sarcoma Service Specification states that at diagnosis or suspected diagnosis, all people with DF must be referred to a Sarcoma Specialist Centre for diagnosis and management. Your MDT will include your clinical nurse specialist, surgeon and oncologists with experience of treating DF.


Treatment for DF depends on the area of the body that is affected, the size of the tumour and how fast it is growing. The treatment you receive will be based on your individual circumstances. Your MDT will discuss your case and decide on what treatment is best for you. You may receive any of the following treatments depending on your specific circumstances.

It also depends on how close your tumour is to important structures in your body such as a major blood vessel or an organ. Your doctor should explain your treatment options to you and why your MDT has made their decisions. DF tumours can be unpredictable, they can stabilise (stop growing) and even regress (shrink). No one knows why this happens. If a DF tumour stabilises or shrinks then you may not need treatment.

In the past, treatment for DF has relied on surgery. Now you are more likely be under an Active Surveillance programme.

In 2018, a meeting was held with over 50 adult and paediatric sarcoma experts from different disciplines, patients and patient advocates from Europe, North America and Japan. They met to agree the most appropriate clinical management of desmoid tumours. Following this, in 2020, a global consensus paper was published with their recommendations. A version for patients has also been published which you can read. 

Types of treatment

Active surveillance

Active surveillance is usually the first approach to treat people who are newly diagnosed with DF. This is sometimes known as a ‘watch and wait’ policy, ‘active monitoring’ or ‘active observation’.

Active Surveillance ensures effective treatment can be held in reserve for if you need it. You will be regularly monitored to ensure treatment is given at the earliest appropriate time.

People diagnosed with DF are usually on active surveillance for 1-2 years. You may be on active surveillance for a shorter or longer time depending on your individual circumstances. If your condition stabilises or regresses, active surveillance will continue. If your condition progresses, then other treatment options will be considered for you.

If you are on active surveillance, you may be worried that your DF is not being treated immediately. However, there are advantages to active surveillance:

  • Treatment options for DF come with side effects. Although these treatments can be very helpful, it is important to use them only if you are having symptoms that affect your quality of life or your tumour has grown greatly
  • Some treatments cannot be given more than once, for example, radiotherapy. Radiotherapy can be helpful to improve your symptoms but it may not shrink the tumour
  • It is possible that having repeated surgery may cause the tumour to be more aggressive in its recurrence and growth


If you are on an Active Surveillance programme you will be monitored regularly by your specialist team. You may be seen in person or remotely by telephone or video call. At each appointment you will be checked for signs that you may need further treatment. This will be done by:

  • Giving you a chance to discuss your symptoms
  • A clinical examination - looking at and feeling the tumour
  • You may also have a scan, such as an ultrasound or MRI

The reasons you may need further treatment could include:

  • You are experiencing symptoms that are affecting your quality of life. For example, increasing pain
  • Your tumour is growing quickly
  • Your tumour has grown and is getting close to important structures in the body like nerves, a major blood vessel or an organ

Symptom management

If you are having symptoms that are affecting your quality of life you should be offered symptom management. You can also speak to your clinical nurse specialist if you are worried about any symptoms you are experiencing. You and your team will need to consider quality of life when considering treatment options and their side effects.

Physiotherapists can provide advice on posture, walking, joint range of movement, strength, performing everyday activities and physical activity, all of which can greatly improve symptom management also. Ask your team for a referral to a physiotherapist if you feel you could benefit from this. You can also ask your GP for help. 

DF and pregnancy

During pregnancy, the rate of growth of the DF may change, sometimes the tumour can grow and then may settle down after pregnancy. Any changes with your tumour can be safely managed and less than half of pregnant women with DF need treatment to manage these changes. DF does not increase the risk of anything going wrong during pregnancy but if you are concerned speak to your doctor or clinical nurse specialist who should be able to reassure you. If you are considering getting pregnant please speak to your specialist doctor or clinical nurse specialist first.

Drugs containing eostrogen

If you're thinking of taking drugs which contain oestrogen, such as oral contraception and those to treat menopausal symptoms, it's worth letting your sarcoma team know as this could affect your DF.


It is sometimes possible for your surgeon to remove the tumour. Many patients are keen to have their tumour removed. In the past, surgery used to include taking the tumour out along with a wide area of normal tissue too. This is known as taking a wide margin. Now it is thought that removing a large amount of tissue around the tumour does not always make a difference to whether it will regrow, so surgeons now aim to just remove the tumour.

Sometimes after surgery for DF, the part of the body where the tumour was removed does not work properly or you are left with cosmetic changes to your physical appearance. Surgery also does not guarantee the tumour will not return. This is why, for most DF patients, surgery is not routinely offered or will only be offered after a period of active surveillance and after their case has been reviewed by an MDT.


Chemotherapy is a treatment that uses drugs to destroy tumour cells. Chemotherapy can help switch off the tumour and make it dormant. This may help with symptoms such as pain. The tumour may get smaller with chemotherapy treatment or stop growing. Chemotherapy can cause side effects so the decision to use it needs to be balanced with how your symptoms are affecting you and how the tumour is growing.

The decision to use chemotherapy is on a case by case basis. It is more likely to be used if your DF is progressing quickly and if your symptoms cannot be managed another way.

Tyrosine Kinase Inhibitors

Tyrosine Kinase Inhibitors (TKIs) are a newer type of treatment called a targeted therapy. They work by blocking growth signals inside the tumour cells. The main drugs used to treat DF this way are called sorafenib, pazopanib and imatinib. Special funding is needed to make imatinib available for DF patients . You can ask your clinical nurse specialist for more information on this type of treatment.

Anti-inflammatory drugs

Nonsteroidal anti-inflammatory drugs (NSAIDs) can be used to treat DF. They have an impact on the nature of the tumour and can reduce any pain or swelling you may be experiencing.

Hormone treatment

Hormones are substances produced naturally in the body that control the activity of cells and organs. Hormonal therapies use drugs to interfere with the way hormones are made or how they work in the body. Tamoxifen is an
antioestrogen drug used to treat breast cancer. It has been found to work in treated DF either using this drug alone or alongside nonsteroidal anti-inflammatory drugs. It is commonly used as the first medical treatment for DF, particularly if the DF is in the abdominal wall.


Radiotherapy uses high-energy radiation beams to destroy tumour cells. It can be used after surgery or as a treatment on its own. It is used to improve symptoms and to try and get the tumour to switch itself off and get smaller. DF patients are usually fit and healthy and radiotherapy can have significant long term side effects, so the decision to use radiotherapy needs to be balanced with how significant the symptoms are. It is rarely used to treat children and younger adults.

Isolated Limb Perfusion

Isolated Limb Perfusion (ILP) is a treatment where chemotherapy drugs are given directly into an arm or leg to treat a tumour. It is used as an alternative to surgery to treat DF in the arm or leg where surgery will cause damage to the arm or leg or make it not work properly. Not all specialist centres offer this treatment. If ILP is considered appropriate for your case, you might need to be referred to a specialist centre with expertise in this procedure.


Cryoablation is increasingly being used to treat DF. It uses extreme cold to freeze the tumour. A needle called a cyroprobe is put through your skin directly into the tumour. A gas is then pumped through the cyroprobe to freeze the tumour.

It can be used to treat tumours that are small and easy to get to through the skin. This technique is not available in every specialist centre. If you are eligible for this treatment your clinician may refer you to a specialist centre with expertise in delivering cryoablation treatment. 

After treatment

After any treatment you receive, you will have regular follow up appointments. These appointments are to check your health and to check the site of your DF. They are also a good opportunity to talk to your doctor or nurse about any concerns you may have. At a follow up appointment you will usually have:

  • A chance to discuss symptoms
  • A physical examination to look for any signs of your DF returning
  • You may have a scan such an ultrasound or MRI


Sometimes DF can come back after it is first treated. This is called a recurrence. Sometimes your DF can be stable for a long time and then start growing again. If you do have a recurrence or your DF starts growing again your doctors will discuss your care in an MDT meeting and consider the best treatment options for you.