Desmoid tumours, also known as aggressive fibromatosis or musculoaponeurotic fibromatosis, are rare tumours that develop from connective (or fibrous) tissue in the body. These tumours are generally benignnot cancerous, can grow but will not spread to other body parts, however they can be aggressive and behave like a cancer.
The body is primarily composed of four main tissue types: muscular, nervous, epithelial, and connective. Muscular tissue is made up of thin and elongated cells (known as muscle fibres), and is responsible for the voluntary and involuntary movement of an organism. Nerve tissue consists of two cell types (neurons and glial cells), and is responsible for the coordination and regulation of many bodily functions. Epithelial tissue forms a covering of all bodily surfaces, line body cavities and hollow organs, and make up majority of gland tissue. It has a variety of functions, including protection, secretion, and absorption of substances. Connective tissue, such as fat (adipose tissue), cartilage, bone, and blood, are responsible for connecting, separating, and supporting all other types of tissues in the body.
As connective tissue is found everywhere in the body, desmoid tumours can develop just about anywhere. However, it is most commonly found in the arms, legs, and abdomen.
Desmoid tumours are more common in females, and are generally diagnosed in people between the ages of 15-40. However, anyone can develop this disease.
Types of Desmoid Tumours
There are three primary types of desmoid tumours, which are categorised by the area of the body they originate from.
Extra-abdominal Desmoid Tumours
Extra-abdominal desmoid tumours are found outside of the abdomen, most commonly in the arms, legs, chest wall or the head and neck region. In rare cases, they can also be found in the bladder or scrotum.
Abdominal Desmoid Tumours
Abdominal desmoid tumours, also known as abdominal wall desmoid tumours, are found within the abdominal wall. The abdominal wall surrounds the abdominal cavity, providing coverage and protection of the organs within this region from damage.
Intra-abdominal Desmoid Tumours
Intra-abdominal desmoid tumours are tumours that develop from the tissue connecting abdominal organs. This can include the mesentery, which is the tissue that provides blood vessels and padding to the intestines.
Treatment
When cancers are detected, they are staged and graded based on size, metastasis, and how the cancer cells look under the microscope. Staging and grading helps your doctors determine the best treatment for you. However, because of how rare desmoid tumours are, there is currently no standard staging and grading system for this disease. Instead of staging and grading, your doctor will recommend a treatment plan based on the following factors:
- Tumour location.
- Your age.
- General health.
- Your treatment preferences.
Your doctor may also recommend genetic testinga procedure that analyses DNA to identify changes in genes, chromosomes and proteins, which can be used to analyse tumour DNA to help determine which treatment has the greatest chance of success, which analyses your tumour DNA and can help determine which treatment has the greatest chance of success. They will then discuss the most appropriate treatment option for you.
Treatment options for desmoid tumours may include:
- Watch and waitthe close monitoring of a cancer without giving treatment until symptoms appear or worsen.
- Surgery to remove as much of the tumour as possible.
- Radiation therapya treatment that uses controlled doses of radiation to damage or kill cancer cells.
- Chemotherapya cancer treatment that uses drugs to kill or slow the growth of cancer cells, while minimising damage to healthy cells.
- Anti-inflammatory medication, potentially including non-steroidal anti-inflammatory drugs (NSAIDs) and Imatinib.
- Hormone therapymedication that alters the levels of certain hormones in the body, such as oestrogen and progesterone.
- Targeted therapymedication that targets specific molecular features of cancer cells.
- Clinical trialsresearch studies performed to test new treatments, tests or procedures and evaluate their effectiveness on various diseases.
- Palliative carea variety of practices and exercises used to provide pain relief and improve quality of life without curing the disease.
Risk Factors
While the cause of desmoid tumours remain unknown, the following factors may increase the likelihood of developing the disease:
- Having familial adenomatous polyposis (FAP).
- Pregnancy (rare).
- Genetic mutation of the adenomatous polyposis coli (APC) gene.
- Severe and/or repeated trauma to the body.
- High levels of the hormone oestrogen.
Not everyone with these risk factors will develop the disease, and some people who have the disease may have none of these risk factors. See your general practitioner (GP) if you are concerned.
Symptoms
The symptoms of a desmoid tumour will often vary based on location. In general, the symptoms of a desmoid tumour may include:
- A mass in the affected area.
- Swelling of affected area.
- Pain or soreness, potentially caused by compressed nerves, blood vessels, and/or muscles.
- Loss of function of affected area.
- Nausea and/or vomiting.
- Abdominal cramping (when tumour is in the abdomen).
- Bowel obstruction (commonly for intra-abdominal tumours), which may cause:
- Bloating.
- Constipation.
- Abdominal pain.
- Ruptured intestines.
- Limping or other difficulties using the legs and feet (if tumour is located on the legs).
- Tingling in affected area, often caused by the tumour compressing nearby nerves and/or blood vessels.
Not everyone with the symptoms above will have cancer, but see your general practitioner (GP) if you are concerned.
Diagnosis
If your doctor suspects you have a desmoid tumour, they may order the following tests to confirm the diagnosis and refer you to a specialist for treatment:
- Physical examinationan examination of your current symptoms, affected area(s) and overall medical history.
- Imaging tests, potentially including:
- MRI (magnetic resonance imaging)a type of medical imaging that uses radiowaves, a strong magnet and computer technology to create detailed images of the body.
- CT (computed tomography) scana type of medical imaging that uses x-rays and computer technology to create detailed images of the body.
- Biopsyremoval of a section of tissue to analyse for cancer cells.