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Frequently Asked Questions (FAQs)

desmoid tumor tendril

Here are some quick answers to common questions about desmoid tumors. Remember to always consult with your healthcare provider if you have questions.

A tumor is an abnormal mass of tissue. It forms when cells grow and divide more than they should or do not die when they are supposed to.1

Desmoid tumors may develop in the soft tissues that connect, support, and surround other body parts (connective tissue). Connective tissue is found all throughout the body. That’s why desmoid tumors can grow anywhere in the body.2 Desmoid tumors are also sometimes called desmoid fibromatosis.2-6

Because desmoid tumors are so rare, a desmoid tumor diagnosis can raise more questions for patients than answers. To learn more about desmoid tumors, click here.

If your care team thinks you may have a desmoid tumor, they should consider imaging and a biopsy.4,7,8 These tests will help them determine if you have a desmoid tumor and what your course of treatment might look like. Don’t be afraid to ask your doctor about these tests if they have not yet been recommended.

Imaging: A CT (computerized tomography) scan, MRI (magnetic resonance imaging),8 and/or ultrasound can see what is happening inside the body. These imaging tests can help doctors understand where the tumor is and what parts of the body are impacted.4,7,9

Biopsy + Beta-Catenin Staining: After imaging, a piece of the suspected tumor will need to be taken out8 (usually with a needle) and examined under a microscope with a special stain to confirm that it is a desmoid tumor.4,7.10 Overproduction of a protein called beta-catenin can be used as a confirmatory indicator to help doctors diagnose desmoid tumors.11,12

NCCN Guidelines for Patients® provides a roadmap to help patients understand their diagnosis and treatment options. According to the NCCN Guidelines for Patients, it is important that a biopsy be performed. Imaging of the primary site with a CT or MRI will be done as needed.13 Otherwise, a wrong diagnosis can lead to delayed or incorrect treatment, or unnecessary surgery. Your doctor may choose to perform additional tests as well. If you have questions about getting diagnosed, be sure to ask your care team.

Based on medical studies, 60% to 98% of desmoid tumors show beta-catenin staining under a microscope,12 so it can be an important clue to diagnosis.  

Beta catenin is a protein found in cells throughout the body. One of the roles of beta catenin is  to help regulate “cell signaling.”3 Cell signaling can instruct cells in the body when to grow and divide.14 Abnormal cell signaling may lead to tumor development and growth.12 Medical experts have found that beta catenin often accumulates excessively in desmoid tumor cells, causing tumors to overgrow.3

Lipomas are the most common type of soft tissue tumor.15 They occur far more frequently than desmoid tumors. 

  • 50% of soft-tissue tumors are lipomas16
  • 3% of soft-tissue tumors are desmoid tumors6

The rarity of desmoid tumors compared to lipomas may be one reason that desmoid tumors could be misdiagnosed as lipomas.17 In fact, among desmoid tumors that are misdiagnosed, up to 40% were initially thought to be lipomas.18,*

From market research conducted by SpringWorks Therapeutics.18

Desmoid tumors and their “tendril-like” growths may be difficult to see fully using imaging tests like MRI, CT scans, or ultrasound.19 This may be another reason that a desmoid tumor could be misdiagnosed as a lipoma or another tumor type.  

It is not clear why some people develop desmoid tumors. However, there are some things that may make certain people more likely to get them than others.

  • Women are approximately 2 to 3 times as likely as men to be diagnosed with a desmoid tumor20-22
  • Recent pregnancy, injury, or surgery may increase risk as well23,24
  • Patients with familial adenomatous polyposis (FAP) have an approximately 850-fold higher risk of developing desmoid tumors than the general population25

If you are diagnosed with a desmoid tumor, you may want to ask your doctor directly about whether it is cancer. They will be able to advise you on the exact status of your tumor and what your next steps might look like.

To learn more about desmoid tumors, click here.

Though they do not metastasize (spread) to other parts of the body, desmoid tumors can grow, and sometimes very quickly.6 Their “tendril-like” growths can attach to and wrap around surrounding tissues and structures.17 If you are diagnosed with a desmoid tumor, your care team may focus on active surveillance to see if your tumor is growing before starting treatment.4

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.17 As these tumors grow, they can put pressure on blood vessels and nerves, or organs, like your intestines and lungs.6,26

While some people may not feel anything, the impact of desmoid tumors and their “tendril-like” growths wrapping around surrounding structures may cause pain (often neuropathic), changes to body shape and physical function, limited range of motion, sleep changes, shortness of breath, and fatigue.6 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.2,27

In rare instances, desmoid tumors can be life-threatening depending on where they are located, how they grow, and your overall health.2,3,5,17 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.

Having FAP increases a person’s risk for developing desmoid tumors. Most often, desmoid tumors in people with FAP occur in abdominal locations.13 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.13

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.8

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

Currently, there are no FDA-approved treatment options indicated for desmoid tumors.28 Once a desmoid tumor has been diagnosed, there are several management options for you and your HCP to consider depending on the size, location, aggressiveness, and discomfort of the tumor.8,12 Current management approaches include:

Active Surveillance: The first step for some people may be to “wait and see.” This may include regular doctor check-ups and frequent imaging tests.8 This will give doctors a chance to understand if your symptoms are changing and see if or how fast the tumor is growing.17,29,30

If the tumor grows quickly, symptoms get worse, or the tumor is in a critical location, your doctor may decide to begin treatment.8,29

Medical Therapy: Currently, there are no FDA-approved treatment options indicated for desmoid tumors.28 However, there are treatments your care team may prescribe to help shrink and/or stabilize the tumor and manage symptoms. The recent clinical guidelines recommend the following treatment options:4,8

  • Tyrosine kinase inhibitors (TKIs, may include sorafenib, pazopanib and imatinib)
  • Chemotherapy (options may include methotrexate and vinblastine/vinorelbine, doxorubicin-based regimens)
  • Nonsteroidal anti-inflammatory drugs (NSAIDs, for pain)

Antihormonal therapies (tamoxifen or toremifene, with or without NSAIDs) do not have guideline recommendations.4,8

Results and side effects can vary from person to person. It may be helpful to talk about what to expect with your care team. Together, you and your care team can come up with strategies to help handle side effects if you experience them.

Surgery: Surgery used to be the most common treatment for desmoid tumors, but it is generally no longer recommended as a first approach in most locations by desmoid tumor experts.2,6 This is because:

  • surgery may require the removal of large amounts of tissue30
  • desmoid tumors often come back after surgery (recurrence)3
  • desmoid tumors may remain stable or resolve on their own30

During surgery, the surgeon tries to remove the entire desmoid tumor and some surrounding healthy tissue to make sure they removed it all. Doctors call this surrounding area a “clear margin” where no tumor cells are visible.29,30

Desmoid tumors include the tumor itself and the “tendril-like” growths that radiate outward.17 These can be far-reaching. Because of this, completely removing the desmoid tumor and getting a clear margin can be difficult. Removing a large amount of tissue could cause some loss of function or changes in appearance.30,31

Desmoid tumors can come back after surgery. It has been reported that they come back about 24% to 77% of the time.22,32 Factors like the location and size of the tumor, as well as age, can influence risk of recurrence.33 So, surgery may not be the best option for everyone.4

Radiation Therapy: Radiation therapy can be used where surgery would not be feasible and medical therapies are not available.4

Cryoablation: Extreme cold is used to destroy tumor tissue.13,34 A cold gas is pumped into the tumor through a thin needle. The tissue thaws and the freezing and thawing are repeated several times to destroy the cells.13,34 Cryoablation can be used for small to medium tumors that are not in the abdomen.17

Clinical Trials: There is a need for more research into targeted, tolerable medications to treat desmoid tumors. You may want to ask your care team about the latest options, what new therapies are being studied in clinical trials, and whether or not you may be a good candidate for a clinical trial.8,35

For more information about treating desmoid tumors, go to NCCN.org and read more about the NCCN Guidelines for Patients® for Soft Tissue Sarcoma.13

Surgery is an option, but is generally not recommended for first-line treatment in most tumor locations by sarcoma specialists.4,8 When making a decision about surgery, doctors will look at the size and location of the tumor, how aggressively it is growing, and the symptoms it’s causing.8,12,29 Some people will have part or all of the desmoid tumor surgically removed, often along with some surrounding healthy tissue. Doctors call this surrounding area a “clear margin” where no cancer cells are visible.4

Desmoid tumors can come back after surgery about 24% to 77% of the time,22,32 so it may not be the best treatment option for everyone. And because these tumors grow into surrounding tissues, it may be difficult to identify clear margins.30,31 Risk factors for recurrence include the location and size of the tumor, as well as age.33

Talk to your doctor to find out if surgery is an appropriate option for you. Also consider asking for a referral to meet with a sarcoma specialist, who has experience and expertise in dealing with soft tissue tumors.

The infiltrative nature of desmoid tumors may make them challenging to remove surgically. Their “tendril-like” growths can extend into layers of tissue beyond the tumor itself.17 In contrast, lipomas are generally well defined within a thin capsule of tissue.36

After surgery, lipomas generally do not recur (come back).15 However, desmoid tumors can come back after surgery. It is reported that they come back 24% to 77% of the time.22,32 The risk of tumors coming back after surgery can be higher for younger patients and those with larger tumors. Tumor location is also important. Desmoid tumors in the extremities (arms, legs, hands, feet), chest wall, and within the abdominal cavity have a higher risk of coming back after surgery.33

Under a microscope, the cells of a lipoma look very different than the cells of a desmoid tumor.12,15 A biopsy of the tumor is the only way to see these differences before surgery. Ask your doctor whether a biopsy is appropriate for you. 

Right now, there is no FDA-approved medication for desmoid tumors.28 However, there are treatments your care team may prescribe to help shrink and/or stabilize the tumor and manage symptoms.

The recent clinical guidelines recommend the following treatment options:4,8

  • Tyrosine kinase inhibitors (TKIs, may include sorafenib, pazopanib, and imatinib)
  • Chemotherapy (options may include methotrexate and vinblastine/vinorelbine, doxorubicin-based regimens)
  • Nonsteroidal anti-inflammatory drugs (NSAIDs, for pain)

Antihormonal therapies (tamoxifen or toremifene, with or without NSAIDs) do not have guideline recommendations.4,8

Remember, results and side effects can vary from person to person. You may want to talk about what to expect with your care team. Together, you can come up with strategies to help handle side effects if you experience them.

It is recommended that you consult with a multidisciplinary care team for the best approach to your care.4,8 It may include a medical oncologist and sarcoma specialist, surgeon, radiologist, pathologist, nurses, your primary care physician, and a mental health professional.13,37

A sarcoma specialist is a doctor who has experience and expertise in dealing with soft tissue tumors, like desmoid tumors. For help finding one, you can use this online search tool.*

The following websites are good places to check:†

Advocacy Groups and Additional Resources*

You may find it helpful to reach out to the organizations listed below for information, support, or to connect with others who are living with desmoid tumors.

DTRF

Rein in Sarcoma

NORD

SARC

You can also visit these websites for additional information about desmoid tumors.

  • Desmoidians on Facebook Link
  • National Cancer Institute Link
  • Find a Sarcoma Center Link
  • NCCN Guidelines for Patients®: Soft Tissue Sarcoma nccn.org

SpringWorks Therapeutics is providing this link to help patients find a sarcoma specialist by region, but SpringWorks had no role in developing this list and inclusion on this list does not represent an endorsement or a recommendation from SpringWorks for any center or physician.

SpringWorks Therapeutics is providing these links to help patients find more information about desmoid tumors, but inclusion on this list does not represent an endorsement or a recommendation from SpringWorks for any group or organization.

  1. NIH. National Cancer Institute. NCI dictionary of cancer terms: tumor. Accessed April 16, 2022. https://www.cancer.gov/publications/dictionaries/cancer-terms/def/tumor.
  2. 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.
  3. Penel N, Chibon F, Salas S. Adult desmoid tumors: biology, management and ongoing trials. Curr Opin Oncol. 2017;29(4):268-274.
  4. 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.
  5. 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.
  6. 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.
  7. Cancer.Net. Desmoid tumor: diagnosis. Accessed February 6, 2022. https://www.cancer.net/cancer-types/desmoidtumor/diagnosis.
  8. 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 June 6, 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.
  9. Cancer.Net. Magnetic resonance imaging (MRI). Accessed April 16, 2022. https://www.cancer.net/navigating-cancercare/diagnosing-cancer/tests-and-procedures/magnetic-resonance-imaging-mri.
  10. Cancer.Net. Biopsy. Accessed April 16, 2022. https://www.cancer.net/navigating-cancer-care/diagnosing-cancer/tests-andprocedures/biopsy.
  11. Carlson JW, Fletcher CDM. Immunohistochemistry for β-catenin in the differential diagnosis of spindle cell lesions: analysis of a series and review of the literature. Histopathology. 2007;51(4):509-514.
  12. 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 [supplementary appendix]. Eur J Cancer. 2020;127:96-107.
  13. 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.
  14. NCI (National Cancer Institute). Definition of cell signaling. Accessed October 13, 2022. https://www.cancer.gov/publications/dictionaries/cancer-terms/def/cell-signaling.
  15. Kolb L, Yarrarapu SNS, Ameer MA, et al. Lipoma. [Updated 2022 Jul 11]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK507906/.
  16. Li M, Zhang L, Xu XJ, Shi Z, Zhao XM. CT and MRI features of tumors and tumor-like lesions in the abdominal wall. Quant Imaging Med Surg. 2019 Nov;9(11):1820-1839.
  17. 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.
  18. Data on file. SpringWorks Therapeutics.
  19. Rosa F, Marinetti C, Piscopo F, et al. Multimodality imaging features of desmoid tumor: a head-to-toe spectrum. Insights into Imaging. 2020 Dec;11(1):1-3.
  20. 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.
  21. 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.
  22. Skubitz KM. Biology and treatment of aggressive fibromatosis or desmoid tumor. Mayo Clin Proc. 2017;92(6):947-964.
  23. 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.
  24. 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.
  25. Gurbuz AK, Giardiello FM, Petersen GM, et al. Desmoid tumours in familial adenomatous polyposis. Gut. 1994;35(3):377-381.
  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. 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.
  28. Riedel RF. Agulnik M. Evolving strategies for management of desmoid tumor. Cancer. 2022;128(16):3027-3040.
  29. Cancer.Net. Desmoid tumor: types of treatment. Accessed April 16, 2022. https://www.cancer.net/cancertypes/desmoidtumor/ types-treatment.
  30. Kasper B, Baumgarten C, Bonvalot S, et al; Desmoid Working Group. Management of sporadic desmoid-type fibromatosis: a European consensus approach based on patients’ and professionals’ expertise—a sarcoma patients EuroNet and European Organisation for Research and Treatment of Cancer/Soft Tissue and Bone Sarcoma Group initiative. Eur J Cancer. 2015;51(2):127-136.
  31. Ballo MT, Zagars GK, Pollack A, Pisters PWT, Pollock RA. Desmoid tumor: prognostic factors and outcome after surgery, radiation therapy, or combined surgery and radiation therapy. J Clin Oncol. 1999;17(1):158-167.
  32. Easter DW, Halasz NA. Recent trends in the management of desmoid tumors. Summary of 19 cases and review of the literature. Ann Surg. 1989;210(6)765-769.
  33. Crago AM, Denton B, Salas S, et al. A prognostic nomogram for prediction of recurrence in desmoid fibromatosis. Ann Surg. 2013;258(2):347-353.
  34. NCI (National Cancer Institute). Dictionary of cancer terms: cryoablation. Accessed October 22, 2022. https://www.cancer.gov/publications/dictionaries/cancer-terms/def/cryoablation.
  35. Cancer.Net. About clinical trials. Accessed April 16, 2022. https://www.cancer.net/ research-and-advocacy/clinical-trials/aboutclinical-trials.
  36. Charifa A, Azmat CE, Badri T. Lipoma Pathology. [Updated 2021 Dec 12]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK482343/.
  37. Cancer.Net. The oncology team. Accessed April 16, 2022. https://www.cancer.net/navigating-cancer-care/cancerbasics/cancer-care-team/oncology-team.