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Disease Profile

Desmoid tumor

Prevalence estimates on Rare Medical Network websites are calculated based on data available from numerous sources, including US and European government statistics, the NIH, Orphanet, and published epidemiologic studies. Rare disease population data is recognized to be highly variable, and based on a wide variety of source data and methodologies, so the prevalence data on this site should be assumed to be estimated and cannot be considered to be absolutely correct.


US Estimated

Europe Estimated

Age of onset





Autosomal dominant A pathogenic variant in only one gene copy in each cell is sufficient to cause an autosomal dominant disease.


Autosomal recessive Pathogenic variants in both copies of each gene of the chromosome are needed to cause an autosomal recessive disease and observe the mutant phenotype.


dominant X-linked dominant inheritance, sometimes referred to as X-linked dominance, is a mode of genetic inheritance by which a dominant gene is carried on the X chromosome.


recessive Pathogenic variants in both copies of a gene on the X chromosome cause an X-linked recessive disorder.


Mitochondrial or multigenic Mitochondrial genetic disorders can be caused by changes (mutations) in either the mitochondrial DNA or nuclear DNA that lead to dysfunction of the mitochondria and inadequate production of energy.


Multigenic or multifactor Inheritance involving many factors, of which at least one is genetic but none is of overwhelming importance, as in the causation of a disease by multiple genetic and environmental factors.


Not applicable


Other names (AKA)

Fibromatosis, familial infiltrative; FIF; Familial infiltrative fibromatosis;


Congenital and Genetic Diseases; Rare Cancers


The following summary is from Orphanet, a European reference portal for information on rare diseases and orphan drugs.

Orpha Number: 873

A desmoid tumor (DT) is a benign, locally invasive soft tissue tumor associated with a high recurrence rate but with no metastatic potential.

DTs account for < 3% of soft tissue tumors. Their annual incidence is estimated to range between 1/250,000-1/500,000. They predominantly affect women and can occur between the ages of 15-60 years, but frequently during early adolescence and with a peak age of about 30 years.

Clinical description
In principle, DTs can occur in any part of the body: extra-abdominally (neck, shoulders, upper limbs, gluteal region), abdominally (originating from muscle fascia or the abdominal/chest wall), and more rarely intra-abdominally in the mesentery or retroperitoneum. Usually, they are firm and smooth palpable masses upon discovery. Depending on the location of the tumor, symptoms may include pain, fever, and functional impairment or loss of function of the organ involved. DTs may appear after surgical resections, typically after caesarian section. Intra-abdominal DTs are often observed in patients with an association of familial adenomatous polyposis (FAP) or Gardner syndrome (see these terms).

DTs result from the proliferation of well-differentiated myofibroblasts. The exact etiopathogenetic mechanism is still unknown, but they seem to have a multi-factorial origin with hormonal and genetic factors being involved. Somatic mutations in the CTNNB1 gene (3q21) encoding beta-catenin have been found in about 85 % of sporadic cases. In cases with FAP, DTs have been associated with mutations in the tumor suppressor gene APC (5q21-q22) encoding the adenomatous polyposis coli protein.

Diagnostic methods
Initial diagnosis is based on imaging techniques (computed tomography and magnetic resonance imaging) revealing the presence of an infiltrative growing mass. Diagnosis is confirmed by tumor biopsy showing abundant collagen surrounding elongated spindle-shaped cells containing small and regular nuclei and pale cytoplasm. Immunohistological examination shows expression of muscle cell markers (e.g. actin, desmin, vimentine) and absence of CD34. Moreover, diagnosis can be confirmed by screening for mutations of CTNNB1.

Differential diagnosis
The differential diagnosis is broad with fibrosarcomas on the one extreme and myofibroblastic processes such as nodular fasciitis and even hypertrophic scars and keloids on the other. The differential diagnosis of intra-abdominal DTs includes gastrointestinal stromal tumors, solitary fibrous tumors, inflammatory myofibroblastic tumors, sclerosing mesenteritis and retroperitoneal fibrosis (see these terms).

Genetic counseling
Most cases are sporadic. Familial cases (5-10 %) are associated with FAP.

Management and treatment
Complete surgical resection remains the therapeutic mainstay of DTs. For unresectable tumors or those not amenable to surgical resection with R0 (microscopic tumor clearance) intent or accompanied by an unacceptable function loss, non-surgical treatments comprise radiotherapy, antiestrogen therapy, non-steroidal anti-inflammatory agents, chemotherapy (e.g. methotrexate, vinblastine/vinorelbine, pegylated liposomal doxorubicin) and/or tyrosine kinase inhibitors (e.g. imatinib, sorafenib). As DTs have a variable and often unpredictable clinical course, a period of watchful waiting is advisable for asymptomatic patients. As DTs often recur, a surveillance strategy every 3-6 months is essential.

Local recurrence occurs in around 70 % of cases. Prognosis depends on the type of tumor. Life expectancy is normal for abdominal and extra-abdominal tumors. However, it is lower in cases of intra-abdominal DTs due to complications such as intestinal obstruction, hydronephrosis or sepsis. Repeated surgical resections are associated with a greater risk of morbidity.

Visit the Orphanet disease page for more resources.


This table lists symptoms that people with this disease may have. For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. This information comes from a database called the Human Phenotype Ontology (HPO) . The HPO collects information on symptoms that have been described in medical resources. The HPO is updated regularly. Use the HPO ID to access more in-depth information about a symptom.

Medical Terms Other Names
Learn More:
80%-99% of people have these symptoms
Abnormality of the abdominal wall
Abnormality of the musculature
Muscular abnormality
Desmoid tumors
Subcutaneous nodule
Firm lump under the skin
Growth of abnormal tissue under the skin

[ more ]

30%-79% of people have these symptoms
Abdominal pain
Pain in stomach
Stomach pain

[ more ]

Abnormality of retinal pigmentation
Epidermoid cyst
Skin cyst
Intestinal polyposis
Intestinal malabsorption
Muscle ache
Muscle pain

[ more ]

5%-29% of people have these symptoms
Joint pain
Chest pain
Colon cancer
Gastrointestinal hemorrhage
Gastrointestinal bleeding
Intestinal obstruction
Bowel obstruction
Intestinal blockage

[ more ]

Limitation of joint mobility
Decreased joint mobility
Decreased mobility of joints
Limited joint mobility
Limited joint motion

[ more ]

Neoplasm of the skin
Skin tumors
Tumor of the skin

[ more ]

Breakdown of bone
Infection in blood stream
Percent of people who have these symptoms is not available through HPO
Autosomal dominant inheritance


Making a diagnosis for a genetic or rare disease can often be challenging. Healthcare professionals typically look at a person’s medical history, symptoms, physical exam, and laboratory test results in order to make a diagnosis. The following resources provide information relating to diagnosis and testing for this condition. If you have questions about getting a diagnosis, you should contact a healthcare professional.

Testing Resources

  • The Genetic Testing Registry (GTR) provides information about the genetic tests for this condition. The intended audience for the GTR is health care providers and researchers. Patients and consumers with specific questions about a genetic test should contact a health care provider or a genetics professional.


    Support and advocacy groups can help you connect with other patients and families, and they can provide valuable services. Many develop patient-centered information and are the driving force behind research for better treatments and possible cures. They can direct you to research, resources, and services. Many organizations also have experts who serve as medical advisors or provide lists of doctors/clinics. Visit the group’s website or contact them to learn about the services they offer. Inclusion on this list is not an endorsement by GARD.

    Organizations Supporting this Disease

      Organizations Providing General Support

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        These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

        Where to Start

          In-Depth Information

          • Medscape Reference provides information on this topic. You may need to register to view the medical textbook, but registration is free.
          • The Monarch Initiative brings together data about this condition from humans and other species to help physicians and biomedical researchers. Monarch’s tools are designed to make it easier to compare the signs and symptoms (phenotypes) of different diseases and discover common features. This initiative is a collaboration between several academic institutions across the world and is funded by the National Institutes of Health. Visit the website to explore the biology of this condition.
          • Online Mendelian Inheritance in Man (OMIM) is a catalog of human genes and genetic disorders. Each entry has a summary of related medical articles. It is meant for health care professionals and researchers. OMIM is maintained by Johns Hopkins University School of Medicine. 
          • Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge.
          • PubMed is a searchable database of medical literature and lists journal articles that discuss Desmoid tumor. Click on the link to view a sample search on this topic.