Desmoid tumor overview
|
Desmoid tumor Microchapters |
|
Diagnosis |
|---|
|
Treatment |
|
Case Studies |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] Associate Editor(s)-in-Chief: Sara Mohsin, M.D.[2]Faizan Sheraz, M.D. [3]
Overview
Desmoid tumors are the benign tumors that arise from monoclonal proliferation of well-differentiated fibroblasts (which are found throughout the body). Main function of fibroblasts is in wound healing and to provide structural support and protection to the vital organs such as lung, liver, blood vessels, heart, kidneys, skin, intestines. Depending upon the underlying etiology, desmoid tumors can be classified as abdominal, intra-abdominal, extra-abdominal, multiple familial, associated with Gardner syndrome and associated with Turcot syndrome. Desmoids can arise in virtually any part of the body. Desmoids appear as well-differentiated, firm overgrowths of fibrous tissue with marked cellularity and aggressive local infiltration. Histologically, desmoid tumors consist of elongated fibroblasts and myofibroblasts which are linearly arranged and are surrounded and separated from each other by collagen. Most common frequent causes of desmoid tumors at molecular level include mutations in the β-catenin gene, CTNNB1, or the adenomatous polyposis coli gene, APC, all involved in Wnt/beta-catenin signaling pathway. Pediatric desmoid tumors have AKT1 E17K, BRAF V600E and TP53 R273H mutations also in addition to CTNNB1 mutations. Desmoid tumors account for approximately 0.03 percent of all neoplasm and less than 3% of all the soft tissue tumors.They are more common in women (of fertile age) than men, and mostly occur in age of 30's to 40's. These tumors can be slow growing or extremely aggressive, musculoaponeurotic tumors without any metastatic potential. When they are aggressive they can cause life threatening problems or even death due to compression of vital organs such as the intestines, kidneys, lungs, blood vessels, and nerves. Common risk factors for desmoid tumors include personal or family history of FAP, Gardner syndrome, Turcot syndrome, female gender, pregnancy, estrogen therapy, history of antecedent surgical or accidental trauma or irradiation at the tumor site, history of breast cancer and androgens.
Desmoids may be diagnosed on an imaging test done for another reason in asymptomatic patients. In symptomatic patients, it can present as a painless or painful mass/lump, insomnia, difficulty moving, nausea, vomiting, anxiety depending upon size and location of tumor. Gold standard for diagnosis is histological examination of a biopsy specimen followed by immunohistochemistry for nuclear beta-catenin. Various imaging studies like CT, MRI, ultrasonography, color doppler, plain radiograph and angiography may aid in further diagnosis and deciding treatment strategy especially for highly recurrent tumors. Wait and watch therapy is applied for treatment of asymptomatic patients. For symptomatic patients various therapeutic options are available such as surgery, radiation therapy, tumor ablation and medical therapy with chemotherapeutic agents, anti-hormonal agents, NSAIDs and tyrosine kinase inhibitors.
Historical Perspective
Muller first coined the term desmoid in 1858 to describe tumors with tendon-like consistency. It origniates from a Greek word "desmos" meaning band or tendon-like. Gradner first described the development of desmoid tumors in FAP patients in 1951.
Classification
Desmoid tumor may be classified according to etiology into 5 subtypes.[1]
Pathophysiology
Desmoid tumor may occur as part of Gardner syndrome. A minority of desmoid tumors are associated with Turcot syndrome, Familial adenomatous polyposis, and estrogen therapy.[2]
Causes
There are no established direct causes for desmoid tumor.
Differentiating Desmoid tumor from other Diseases
Desmoid tumor must be differentiated from acute hematoma, lymphoma, and fibrosarcoma.[1]
Epidemiology and Demographics
Desmoid tumor occurs in less than 0.03% of all tumors. The incidence of desmoid tumor is approximately 30 per 100,000 individuals worldwide. Females are more commonly affected with desmoid tumor than males. Desmoid tumor commonly affects individuals between 20 to 40 years of age.[3][1]
Risk Factors
Risk factors for desmoid disease amongst FAP patients include female sex, a 3' APC mutation, a positive family history and a history of previous abdominal surgery.[4]
Natural History, Complications and Prognosis
If left untreated, desmoid tumor produces few symptoms early in the course. Common complications of desmoid tumor include progression to agressive fibromatosis, involvement of intra abdominal viscera, and metastasis. The prognosis varies with the associated disease of desmoid tumor. Desmoid tumor associated with FAP has the least favorable prognosis.
Diagnosis
History and Symptoms
Symptoms of desmoid tumor include uncharacteristic pain, abdominal mass, nausea, and vomiting.
Physical Examination
Common physical examination findings of desmoid tumor include abdominal tenderness, pallor, and elevated temperature.[1]
CT
CT scan may be diagnostic for desmoid tumor. On CT scan, desmoid tumor is characterized by a well circumscribed mass that is homogeneously or focally hyperattenuating. Desmoid tumor may demonstrate enhancement following administration of intravenous contrast.[2][1]
MRI
Abdominal MRI may be diagnostic of desmoid tumor. On MRI, desmoid tumor is characterized by dense cellularity and loss of signal following fat saturation.[2]
Other Imaging Findings
Other imaging findings of desmoid tumor include ultrasonography, which demonstrates tumor size and location. On ultrasonography, desmoid tumors appear as well-defined lesions with variable echogenicity. The lateral borders may appear ill defined or irregular.[1]
Treatment
Medical Therapy
Medical therapy for desmoid tumor includes antiestrogens (ex. tamoxifen), NSAIDs, chemotherapy or microwave ablation.
Surgery
Surgical resection is not recommended among patients with advanced or metastatic malignancy.[1]
Reference
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 1.6 Economou, Athanasios; Pitta, Xanthi; Andreadis, Efstathios; Papapavlou, Leonidas; Chrissidis, Thomas (2011). "Desmoid tumor of the abdominal wall: a case report". Journal of Medical Case Reports. 5 (1): 326. doi:10.1186/1752-1947-5-326. ISSN 1752-1947.
- ↑ 2.0 2.1 2.2 Desmoid tumor. Dr Tim Luijkx and Radswiki et al. Radiopedia 2015 http://radiopaedia.org/articles/aggressive-fibromatosis. Accessed on January 20, 2015
- ↑ Desmoid tumor. Dr Tim Luijkx and Radswiki et al.Radiopaedia 2015.http://radiopaedia.org/articles/desmoid-tumour. Accessed on January 21, 2016
- ↑ Sinha A, Clark SK (2010). "Risk factors predicting desmoid occurrence in patients with familial adenomatous polyposis: a meta-analysis". Colorectal Dis. 13 (11): no. doi:10.1111/j.1463-1318.2010.02345.x. PMID 20528895.