The treatment of desmoid tumors can be complex, and what works for one person may not necessarily work for another. Experts are continually working toward standardizing protocols based on tumor location, symptoms, and aggressiveness. In 2020, supported by a grant from the DTRF, an international team of experts working in the field of desmoid tumors published evidence-based, consensus guidelines for medical treatment. Known as the Global Consensus Paper on Desmoid Tumor Management, the paper answers critical questions regarding approach to treatment, types of treatments, and pain management.
(Note that the Global Consensus Paper is being updated for publication in early 2024.)
Highlights from the Consensus Paper
- Active surveillance is the well-established primary approach to primary/recurrent sporadic/familial desmoid tumors. (“Sporadic” refers to desmoid tumors that are not inherited. “Familial” refers to desmoid tumors that can be inherited and occur with Familial Adenomatous Polyposis or F.A.P.)
- Surgery is the accepted second-line treatment only for sporadic desmoid tumors located in the abdominal wall failing observation
- Medical therapies are the second-line treatments for sporadic desmoid tumors located at all other sites and for all familial desmoid tumors failing observation
- Local ablative treatments such as cryotherapy or radiotherapy are options that can be considered as an alternative to medical therapies on an individual basis
- Pain control is paramount to improve quality of life, independently of the use of active treatment against the disease.
Below is an algorithm from page 13 of the patient version of the Consensus Paper which describes the general approaches to treatment based on tumor location
Sx*: Surgery is an option if mobility is limited
MTx: Medical treatment
ILP: Isolated limb perfusion.
For more information about desmoid tumor treatment guidelines, visit the Global Consensus Paper on Desmoid Tumor Management page
While treatment can vary depending on the details of each individual case, common treatment approaches include:
Active surveillance (waiting and watching)
Active surveillance is the medical approach that carefully monitors a desmoid tumor through magnetic resonance imaging (MRI) or computed tomography (CT) scans to look for signs of progression or regression (shrinking).1 Because of the unpredictable behaviors of desmoid tumors, active surveillance is the well-established primary approach to primary/recurrent sporadic/familial desmoid tumors. The decision to proceed with active surveillance is on a case-by-case basis and should be discussed with your doctor. You and your care team may decide to pursue treatment at any point due to progression of the tumor or your symptoms.
Medical therapies are the recommended second-line treatments for all sporadic desmoid tumors except for abdominal wall tumors and all familial desmoid tumors failing observation.
A few chemotherapies that are commonly used include: doxorubicin, Doxil (liposomal doxorubicin), dacarbazine, methotrexate, vinorelbine, and vinblastine.1 It is important to note that these chemotherapies can come with varying short or long-term effects and are used in varying combinations.
Tyrosine kinase inhibitors (TKIs)
A newer class of agents called tyrosine kinase inhibitors (TKIs) (e.g., sorafenib, pazopanib, imatinib) are pills taken by mouth that have also been shown to help shrink or slow down the growth in some desmoid tumors.2
Gamma Secretase Inhibitors (GSIs) (Under Study)
Gamma secretase inhibitors are targeted treatments that selectively inhibit a protein called gamma secretase and reduce activation of a pathway that is believed to play a role in the growth of desmoid tumors. These medical therapies are pills that can be taken by mouth at home. Research has shown that gamma secretase inhibitors (GSIs) have shown benefit in desmoid tumors by shrinking or slowing down the growth and improving patient’s symptoms. As with all therapies, gamma secretase inhibitors can also cause side effects that can vary from person to person.
After more than a decade of collaboration among advocates, patients, industry, and medical professionals, the U.S. Food and Drug Administration (FDA) has granted approval to SpringWorks Therapeutics for its gamma secretase inhibitor, OGSIVEO™ (nirogacestat), for the treatment of adults with progressing desmoid tumors.
Learn more (recorded prior to FDA approval):
In Part A of its Phase 2/3 clinical trial, the drug AL102 showed positive interim results. Part B/Phase 3 of the trial is currently underway.
Anti Hormonal Therapies/Non-steroidal anti-inflammatory drugs (NSAIDs)
“Treatment might include nonsteroidal anti-inflammatory drugs (NSAIDs). NSAIDS help reduce fever, swelling, pain, and redness. Sulindac (Clinoril) and celecoxib (Celebrex) are NSAIDs that are commonly prescribed for people with symptoms.”3
Surgery is no longer recommended as a first-line treatment for desmoid tumors due to the high rate of recurrence after surgery (25-60%)4, as well as the chance that a tumor might regress (shrink) on its own without intervention (20-30%).1
Surgery is the accepted second-line treatment only for sporadic desmoid tumors located in the abdominal wall failing observation.1
When surgeries are appropriate, fresh desmoid tissue samples can be collected for research. Your fresh desmoid tumor tissue sample could hold the key to unlocking new discoveries about what drives desmoid tumors.
A Note About Surgery & Recurrence
Historically, surgery was recommended as the first line of treatment. However, research has shown that desmoid tumors have a high risk of local recurrence even with good surgical margins. While statistics vary, the risk of local recurrence (returning at or near the original site) remains between 25-60% for patients.4 Depending on the tumor location, surgery also can cause significant morbidity due to the wide margins needed to remove the whole tumor. Desmoid tumors often have infiltrating tumor borders, which can appear as thin tendrils that reach into nearby tissues. This can make it difficult for surgeons to obtain negative margins, causing an increase in the surgical area or the likelihood of recurrence. In addition, desmoid tumors can still recur even in the presence of negative margins. They can also sometimes recur as multifocal –- multiple tumors within the same general body part. Accordingly, surgery is no longer recommended as a first-line treatment for most desmoid tumors. The decision to undergo surgery is a complex one and should be carefully considered.
Scientific research has shown that some types of desmoid tumors have much higher risk of recurrence after surgery than others.
Dr. Aimee Crago of Memorial Sloan Kettering Cancer Center created a nomogram which can be used to help predict the risk of recurrence following surgical resection of a desmoid tumor. Please read the disclaimer on the Memorial Sloan Kettering nomogram page and discuss the results with your clinician for further context and understanding.
All nomograms are estimations and are not always accurate. When making a decision to undergo surgery, you should have an open conversation with your surgeon and medical oncologist about the risk of recurrence, time to recurrence and the short-term and long-term side-effects of the surgery.
Ablations can use heat or cold to kill desmoid tumor cells. With cryoablation, probes are inserted directly into the tumor and use the cold to damage and kill tumor cells.5 High Intensity Focused Ultrasound (HIFU)[Link to glossary term “HIFU”] is a minimally invasive procedure that focuses ultrasound waves directly to the tumor with the aim of killing the tumor cells.6
These are emerging techniques, and the experience to date is limited to a few, specialized medical centers, and the long-term results are not yet known. In conclusion, the decision to undergo ablation (hot, cold or ultrasound) is a very technical and complex one and needs to be discussed carefully with the interventional radiologist and your medical and surgical oncologist.
“Cryoablation and HiFU”
DEE (intra-arterial doxorubicin drug-eluting embolization)
Doxorubicin Eluting Embolization (DEE), a type of trans-arterial chemoembolization (TACE), is a method to treat desmoid tumors by exposing the tumor to a high concentration of doxorubicin while minimizing the doxorubicin exposure to the rest of the body. In DEE a pharmacist will first mix doxorubicin with drig-eluting microparticles designed to soak up the drug in the bottle but release it in the body. The treatment is then performed by an Interventional Radiologist who will will make a tiny incision to allow the navigatation of a catheter into the arterial blood supply of the Desmoid tumor. Once in position, the doxorubicin loaded micro-beads are released into the tumor tissue and there they slowly elute the chemotherapy. The procedure is usually performed using local anesthesia and sedation, and takes a 2-3 hours. Patients typically undergone two to three procedures to treat the entire desmoid. Large and rapidly growing tumors may require more. DEE is usually offered after failure of at least one systemic therapy. Generally, DEE is performed for larger tumors (>5cm diameter) or smaller tumors if Cryoablation risks Neuro vascular injury.
DEE for Desmoid tumors was first described in 2018 (https://pubmed.ncbi.nlm.nih.gov/30075974/), with additional reports published in 2022 (https://pubmed.ncbi.nlm.nih.gov/36291829/ and https://pubmed.ncbi.nlm.nih.gov/35441242/). Following the promising results seen in these preliminary studies, a dedicated multi center prospective trial is in the works with sites at the Royal Marsden in London, LMU in Munich, University of Heidelberg, Italian National Cancer Institute in Milan and at Share Zedek Medical Center in Jerusalem. Other sites with experience in DEE include Hong Kong Childrens Hospital; Kids Cancer Center in Sydney and Memorial Sloan Kettering Cancer Center in NY.
Q&A: Dr. Eldad Elnekave Explains DEE For Desmoid Tumors
In general, many sarcoma experts do not recommend radiation for desmoid tumors due to the chance of developing a radiation-induced sarcoma. However, radiation therapy may be considered to be an option for certain patients in specific circumstances. Your entire health care team should be consulted if this option is being considered.
Imaging and Monitoring
MRI vs. CT Scan
To monitor and measure a desmoid tumor, magnetic resonance imaging (MRI) is the imaging modality of choice in most cases. MRI has superior soft tissue contrast compared to computed tomography (CT) scans. In other words, desmoid tumors are easier to see on MRI against a background of other soft tissues such as muscle.
In addition, MRI is more accurate at assessing the degree of cellularity (the quantity of active tumor cells shown via T2 signal when compared to CT scans, which is beneficial for determining treatment response. Additionally, unlike X-rays and CT scans, MRI does not emit ionizing radiation.
CT is usually the modality of choice for imaging mesenteric desmoid tumors because bowel motion can make it difficult to see these tumors on MRI. However, once the location of the desmoid tumor is identified with a baseline CT, MRI can be used for follow-up imaging in order to eliminate the radiation exposure one receives from repeated CT scans.
Importance of T2 Signal
MRI is performed using a number of different sequences which highlight different types of tissue in the human body. One sequence, called “T2 weighted images,” highlights tissues which contain various amounts of water. Tissues with a high fluid (water) component are bright on T2-weighted images or “high signal on T2 weighted images.” Desmoid tumors contain active fibroblasts which have a component of fluid in their cells and extracellular spaces, and therefore, are high in T2 signal.
Desmoid tumors also contain collagen (which is produced by the fibroblasts). Collagen alone has very little water content, and therefore, is low in T2 signal. When desmoid tumors contain active fibroblasts in their early, growing stages they are called “cellular” desmoid tumors because they have a high proportion of cells and relatively less collagen. These cells and their large extracellular spaces are bright in T2 signal. However, when the fibroblasts regress over time, leaving mostly collagen behind, desmoid tumors become low in T2 signal and will no longer grow. Reducing the cellularity of desmoid tumors, and therefore, their growth potential, is one of the goals of systemic therapy, and can be monitored using MRI.
For more information, please read the paper “Association of MRI T2 Signal Intensity With Desmoid Tumor Progression During Active Observation: A Retrospective Cohort Study.”
Measuring tumor response to treatment
“Response Evaluation Criteria in Solid Tumors” (known as RECIST) is a standard methodology of measuring a patient’s tumor response to treatment. However, research shows that it is not always the best method to measure treatment outcomes for desmoid tumor patients.
Currently required by the FDA in clinical trials to assess if a tumor is progressing, stable, or responding to treatment, RECIST relies on certain measurements to monitor response — such as “longest dimension” — which may not accurately reflect the typical response of desmoid tumors to treatments. RECIST is strictly measurement-based and does not factor in other positive indicators that do not involve changes in lateral tumor measurement (such as changes in T2 signaling, tumor volume, quality of life, etc). To address the RECIST shortcomings, the DTRF, our medical advisors, and pharmaceutical medical professionals developed a Radiomics Working Group[Link to “Radiomics Working Group” page] in late 2021. This group is identifying better methods for measuring treatment response.
Desmoids & Familial Adenomatous Polyposis (F.A.P.)
A small number of desmoid tumors arise in the context of a genetic cancer predisposition syndrome called familial adenomatous polyposis, or F.A.P. These desmoid tumors are the result of a mutation in the adenomatous polyposis coli (APC) gene. F.A.P.-associated desmoid tumors are most commonly found within the abdomen and may be larger and multifocal.2 Approximately 10-25% of FAP-affected individuals will develop a desmoid tumor in their lifetime.4 Tumor treatment may vary if a desmoid tumor is associated with F.A.P. in part because the APC gene mutation is in every cell of the patient’s body.
Learn more about the treatment of desmoid tumors for patients with F.A.P.
Your Care Team
It is important for a sarcoma specialist to evaluate and treat individuals with desmoid tumors. These specialists are typically found at major academic medical centers and can help support care through a robust multidisciplinary team of doctors knowledgeable in desmoid tumor care. This team may include individuals from medical oncology, surgical oncology, radiology, interventional radiology, and pathology. These major medical centers may have designations as a National Comprehensive Cancer Network (NCCN) or as a Sarcoma Alliance for Research through Collaboration (SARC) center.
It is important to discuss your treatment plan with your entire care team, and decide what is best for your specific case. For tips on how to navigate your desmoid tumor treatment plan with your care team, check out this video from Dr. Haddox
LIVE: “Getting the Most Out of Your Consultation and Treatment Plan”
Table of Contents
Watch our past Patient Meeting webinars on the topics of treatment options to learn more about the various approaches to managing desmoid tumors:
“An Overview of Medical Desmoid Tumor Treatments”
“Therapies and Clinical Trials for Desmoid Tumors”
“FAP and Medical Therapies”
Explore all past Patient Meeting Presentations & Media to learn more.
Find More Answers
The Global Consensus Paper answers critical questions regarding approach to treatment recommendations, types of treatments, and pain management for desmoid tumors.
If you are facing challenges in your desmoid tumor treatment, your case may be eligible for your doctor to present at our quarterly Virtual Tumor Board, led by Dr. Aaron Weiss.
A Helping Hand Is Within Reach
Our annual DTRF Together We Will Weekend is a time for patients, family, and friends to connect with each other and participate in informative lectures and roundtables on desmoid tumors and race/walk in our Running for Answers 5K.