What is a desmoid tumor?

Desmoid tumors are powerful—but so is knowledge
desmoid tumor tendril

Understanding this rare disease

Woman thinking

Because desmoid tumors are rare and may not be top of mind for physicians, trying to learn about your condition can be confusing.

One website may tell you one thing or refer to a desmoid tumor in a certain way, while another, or even your doctor, may refer to it in a completely different way. Always speak with your doctor if you have questions.

There is potential for desmoid tumors to be misdiagnosed as another disease. Common misdiagnoses include:1-3,*

  • Overgrown scars (like hypertrophic scars or keloids)
  • Different cancer types (like low-grade sarcomas or gastrointestinal stromal tumor (GIST))
  • Noncancerous growths (like nodular fasciitis, lipoma, fibroma, schwannoma, or leiomyoma)

It’s completely normal for these words to be unfamiliar. Talking about a rare disease can feel like learning a new language. If you’re ever confused about a term, it’s a good idea to ask your doctor to explain it.

Get ready to talk to your doctor—download the discussion guide below to guide your conversation.

From market research conducted by SpringWorks Therapeutics.

A tumor is an abnormal mass of tissue. It forms when cells grow and divide more than they should or don’t die when they should.4

Desmoid tumors may develop in the soft tissues that connect, support, and surround other body parts (connective tissue). Connective tissue is found all throughout in the body. That’s why desmoid tumors can grow anywhere in the body.5 Desmoid tumors are also sometimes called desmoid fibromatosis.5, 7-10

Desmoid tumors are very rare



of soft tissue tumors are desmoid tumors10,11

Mine grows and it takes over. I have a whole bunch of empty spaces because they had to take out a bunch of muscle. I just wish that there was something that explained it easily.

Amy, patient with a desmoid tumor

Amy smiling

Who gets desmoid tumors?

There are approximately 1000 to 1650 annual cases in the United States12-14

Most patients are diagnosed between 20 and 44 years of age13

Women are approximately 2 to 3 times more likely than men to be diagnosed2,13,15

Recent pregnancy, injury, or surgery may increase risk of developing a desmoid tumor16,17

Patients with a family history of familial adenomatous polyposis (FAP) have an approximately 850-fold higher risk of developing desmoid tumors than the general population18.

What is familial adenomatous polyposis (FAP)?

FAP is a medical syndrome that can cause polyps (growths) in the colon to become cancerous.19,20

FAP is an inherited syndrome. This means that an abnormal gene has been passed to a person’s DNA from a parent.15 The abnormal gene behind FAP is known as APC (adenomatous polyposis coli).19,20

Having FAP can increase a person’s risk for developing desmoid tumors. Most often, desmoid tumors in people with FAP occur in abdominal locations.20 Doctors who diagnose desmoid tumors will want to know about any family history of FAP. A genetic test for FAP may be recommended for people who have a desmoid tumor.19,20

Sometimes, it’s recommended that people with FAP have a colectomy (surgery to remove the colon) as a way to prevent colon cancer. For some patients, this procedure can increase risk for desmoid tumors developing in the future.20

For more information about FAP or if you have additional questions, please ask your doctor.

Desmoid Tumors: Symptoms

While some people may not feel a thing, the tumor and its “tendril-like” growths may wrap around nearby structures, causing pain (often neuropathic, which is a nerve problem that causes pain), changes to body shape and physical function, limited range of motion, sleep changes, shortness of breath, and fatigue.10,21 While these are some of the physical effects you may experience when living with a desmoid tumor, remember that these effects can be different for each person, often depending on the location of your tumor.22

Desmoid Tumor Symptoms can include10,21:

  • Pain
  • Limited range of motion
  • Fatigue
  • Impaired mobility
  • And more

Desmoid tumors can grow quickly, slowly, or sometimes not at all, but will not metastasize or spread to other parts of the body. In rare cases, they may even go away on their own.10 However, you may have heard desmoid tumors described as locally aggressive or invasive. This means that their “tendril-like” growths can attach to and wrap around surrounding tissues and structures.22 As tumors grow, they can put pressure on blood vessels and nerves, or on important organs like your intestines or lungs.6,10

I try to educate people that I look fine, I do. But you don’t see what’s on the inside.

Brad, patient with a desmoid tumor

Brad smiling

In rare instances, desmoid tumors can be life-threatening depending on where they are located, how they grow, and your overall health.7,9 However, building a care team with the right specialists can help you get the best care for your specific needs. That’s why it’s so important to talk to your doctor about the location of your tumor and symptoms you may be experiencing.

It wasn’t until after I failed on several treatments that I realized this was serious. That’s when I started doing my own research.

Brad, patient with a desmoid tumor

Brad in front of bleachers

Living with a desmoid tumor

Living with a desmoid tumor can feel uncertain. It can lead to anxiety and depression.23 Sometimes, it may even feel like the tumor and its “tendril-like” growths are taking over your whole life—not just physically, but emotionally, socially, and even professionally.21,24 The first step you can take is to learn everything that you can. This way, you can feel more in control of your condition. Consider sharing resources you find helpful, so others can understand the disease, too.


View the video to help clear the way for a new understanding of desmoid tumors and what it’s like living with them every day.

Desmoid tumors can show up in different places

It’s difficult to predict where and how desmoid tumors can occur in your body. And each location can have different symptoms associated with it. For some people, the pain and symptom burden can lead to anxiety and depression.21,25 Other people frequently report concern around altered appearance, nerve pain, and decreased range of motion. Quality of life can be impacted by fear, difficulty sleeping, and apprehension about a lack of knowledge among healthcare professionals.21

Different tumor locations can lead to different symptoms

Because each tumor is unique, the symptoms and burdens that come with it can be just as unique.



Potential Symptoms and Complications

Intra-abdominal(including the mesentery, a layer of tissue surrounding and supporting the intestines) 10,26


Blockage of the intestines, ureters, or arteries in the digestive system, pain, muscle wasting and weight loss, malaise (general discomfort), or abdominal swelling10,26,27

NOTE: The mesentery is a continuous set of tissues located in your abdomen. It attaches your intestines to the wall of your abdomen and holds them in place28

Abdominal Wall


Large tumors may cause skin stretching and compress the bowel or bladder29

Legs and Feet


Limited movement, pain, muscle stiffness, or deformity10,30



Shortness of breath, difficulty swallowing, infiltration of the membranes surrounding the lungs, rib or spinal involvement, bone erosion, or pain10,26,31,32

Arms and Hands


Restricted movement, pain, muscle and ligament involvement, limb weakness, or deformity10,33

Head and Neck


Pain, neurologic deficit, wrapping and restriction of vital structures like the airway or blood vessels that can become life-threatening7,34



Symptoms and complications are dependent on the tumor location9,10,21

There can be a lot of uncertainty when it comes to having desmoid tumors. Having the right care team by your side can help you feel more confident about your journey and the treatment decisions you make together.

  1. Data on file. SpringWorks Therapeutics.
  2. Penel N, Coindre JM, Bonvalot S, et al. Management of desmoid tumours: a nationwide survey of labelled reference centre networks in France. Eur J Cancer. 2016;58:90-96.
  3. Huss S, Nehles J, Binot E, Wardelmann E, et al. b-Catenin (CTNNB1) mutations and clinicopathological features of mesenteric desmoid-type fibromatosis. Histopathology 2013, 62, 294–304. DOI: 10.1111/j.1365-2559.2012.04355.x
  4. NIH. National Cancer Institute. NCI dictionary of cancer terms: tumor. Accessed April 16, 2022. https://www.cancer.gov/publications/dictionaries/cancer-terms/def/tumor.
  5. NIH. National Cancer Institute Center for Cancer Research. Desmoid tumor. Accessed April 14, 2022. https://www.cancer.gov/pediatric-adult-rare-tumor/rare-tumors/rare-soft-tissue-tumors/desmoid-tumor.
  6. Cancer.Net. Desmoid tumor: symptoms and signs. Accessed April 16, 2022. https://www.cancer.net/cancer-types/desmoidtumor/symptoms-and-signs.
  7. Penel N, Chibon F, Salas S. Adult desmoid tumors: biology, management and ongoing trials. Curr Opin Oncol. 2017;29(4):268-274.
  8. Gronchi, A, et al. Desmoid Tumor Working Group. The management of desmoid tumours: a joint global consensus-based guideline approach for adult and paediatric patients. Eur J Cancer. 2020;127:96-107.
  9. Joglekar SB, Rose PS, Sim F, Okuno S, Petersen I. Current perspectives on desmoid tumors: the Mayo Clinic approach. Cancers (Basel). 2011;3(3):3143-3155.
  10. Constantinidou A, Scurr M, Judson I, Litchman C. Clinical presentation of desmoid tumors. In: Litchman C, ed. Desmoid Tumors. Springer; 2012:chap 2. Accessed May 1, 2022. https://www.researchgate.net/publication/226455135.
  11. Cancer.Net. Desmoid tumor: statistics. Accessed April 15, 2022. https://www.cancer.net/cancer-types/desmoidtumor/statistics.
  12. Orphanet Report Series: Rare Diseases Collection. Prevalence and incidence of rare diseases: bibliographic data. Number 1, January 2022. Accessed April 28, 2022. https://www.orpha.net/orphacom/cahiers/docs/GB/Prevalence_of_rare_diseases_by_alphabetical_list.pdf.
  13. van Broekhoven DLM, Grünhagen DJ, den Bakker MA, van Dalen T, Verhoef C. Time trends in the incidence and treatment of extra-abdominal and abdominal aggressive fibromatosis: a population-based study. Ann Surg Oncol. 2015;22(9):2817-2823.
  14. U.S. Department of Commerce. News Blog. U.S. population estimated at 332,403,650 on Jan. 1, 2022. Accessed April 28, 2022. https://www.commerce.gov/news/blog/2022/01/us-population-estimated-332403650-jan-1-2022.
  15. Skubitz KM. Biology and treatment of aggressive fibromatosis or desmoid tumor. Mayo Clin Proc. 2017;92(6):947-964.
  16. Lopez R, Kemalyan N, Moseley HS, Dennis D, Vetto RM. Problems in diagnosis and management of desmoid tumors. Am J Surg. 1990;159(5):450-453.
  17. Fiore M, Coppola S, Cannell AJ, et al. Desmoid-type fibromatosis and pregnancy: a multi-institutional analysis of recurrence and obstetric risk. Ann Surg. 2014;259(5):973-978.
  18. Gurbuz AK, Giardiello FM, Petersen GM, et al. Desmoid tumours in familial adenomatous polyposis. Gut. 1994;35(3):377-381.
  19. Referenced with permission from the NCCN Guidelines for Patients® for Soft Tissue Sarcoma, V.1.2020.© National Comprehensive Cancer Network, Inc. 2020. All rights reserved. Accessed August 4, 2022. To view the most recent and complete version of the guideline, go online to NCCN.org. NCCN makes no warranties of any kind whatsoever regarding their content, use, or application, and disclaims any responsibility for their application or use in any way.
  20. Referenced with permission from the NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines®) for Soft Tissue Sarcoma V.2.2022. © National Comprehensive Cancer Network, Inc. 2022. All rights reserved. Accessed May 23, 2022. To view the most recent and complete version of the guideline, go online to NCCN.org. NCCN makes no warranties of any kind whatsoever regarding their content, use or application and disclaims any responsibility for their application or use in any way.
  21. Gounder MM, Maddux L, Paty J, Atkinson TM. Prospective development of a patient-reported outcomes instrument for desmoid tumors or aggressive fibromatosis. Cancer. 2020;126(3):531-539.
  22. Kasper B, Baumgarten C, Garcia J, et al. Desmoid Working Group. An update on the management of sporadic desmoid-type fibromatosis: a European Consensus Initiative between Sarcoma Patients EuroNet (SPAEN) and European Organization for Research and Treatment of Cancer (EORTC)/Soft Tissue and Bone Sarcoma Group (STBSG). Ann Oncol. 2017;28(10):2399-2408.
  23. Ingley KM, Klein R, Theobalds N, et al. High prevalence of persistent emotional distress in desmoid tumor. Psycho-Oncology. 2020;29(2):311-320.
  24. Timbergen MJM, van de Poll-Franse LV, Grünhagen DJ, et al. Identification and assessment of health-related quality of life issues in patients with sporadic desmoid-type fibromatosis: a literature review and focus group study. Qual Life Res. 2018;27(12):3097-3111.
  25. Husson O, Younger E, Dunlop A, et al. Desmoid fibromatosis through the patients’ eyes: time to change the focus and organisation of care? Support Care Cancer. 2019;27(3):965-980.
  26. Shinagare AB, Ramaiya NH, Jagannathan JP, et al. A to Z of desmoid tumors. AJR Am J Roentgenol. 2011;197(6):W1008-W1014.
  27. Tchangai BK, Tchaou M, Alassani F, et al. Giant abdominopelvic desmoid tumour herniated trough perineum: a case report. J Surg Case Rep. 2021;2021(8):rjab295. doi:10.1093/jscr/rjab295.
  28. NCI (National Cancer Institute). Dictionary of cancer terms: mesenteric membrane. Accessed October 21, 2022. https://www.cancer.gov/publications/dictionaries/cancer-terms/def/mesenteric-membrane.
  29. Koshariya M, Shukla S, Khan Z, et al. Giant desmoid tumor of the anterior abdominal wall in a young female: a case report. Case Rep Surg. 2013;2013:780862.
  30. McDonald ES, Yi ES, Wenger DE. Best cases from the AFIP: extraabdominal desmoid-type fibromatosis. Radiographics. 2008;28(3):901-906.
  31. Abrão FC, Waisberg DR, Fernandez A, et al. Desmoid tumors of the chest wall: surgical challenges and possible risk factors. Clinics (Sao Paulo). 2011;66(4):705-708.
  32. Xie Y, Xie K, Gou Q, He J, Zhong L, Wang Y. Recurrent desmoid tumor of the mediastinum: a case report. Oncol Lett. 2014;8(5):2276-2278.
  33. Scaramussa FS, Castro UB. Desmoid tumor in hand: a case report. SM J Orthop. 2016;2(3):1036.
  34. Baranov E, Hornick JL. Soft tissue special issue: fibroblastic and myofibroblastic neoplasms of the head and neck. Head Neck Pathol. 2020;14(1):43-58.
  35. Braschi-Amirfarzan M, Keraliya AR, Krajewski KM, et al. Role of Imaging in Management of Desmoid-type Fibromatosis: A Primer for Radiologists. Radiographics. 2016;36(3):767-782.