Extra-abdominal Desmoids Research Articles

The Clinical Features of Multicentric Extra-abdominal Desmoid Tumors.

Extra-abdominal desmoid tumors often occur in the necks, shoulder, chest wall, back, arm, buttock, thigh and leg. Multicentric extra-abdominal desmoids are rather rare and seem to have other clinical features. The aim of our study was to investigate clinical features, especially multicentric occurrence of extra-abdominal desmoid tumors. A total of 135 patients diagnosed with extra-abdominal desmoid were enrolled in this study from January 2005 to December 2019 at the Cancer Institute Hospital of The Japanese Foundation for Cancer Research. The operative procedure was principally wide excision. The clinicopathological factors [e.g., age, gender, pain, restriction of range of motion (ROM), tumor site, tumor size, surgical margin, multicentric occurrence, local recurrence, tumoral regression] were collected and assessed by univariate analysis. We assessed how multicentric occurrence influenced clinicopathological factors of desmoid tumors. The median follow-up was 39.9 months (range=0.29-259 months). Among 135 patients, 20 had multicentric occurrence. Multicentric extra-abdominal desmoids occurred in the neck in six cases, shoulder in four, chest wall in three, back in three, thigh in two and leg in two. In the case of multicentric occurrence on thighs and legs, tumors arose not in the anterior compartment but in the posterior compartment. Univariate analysis showed association of multicentric extra-abdominal desmoids with high local recurrence (p=0.0003), restriction of ROM (p=0.0012) and tumor size larger than 5 cm (p=0.04) but surgical margins were not correlated with local recurrence (p=0.37). Surgery should be performed in those who have severe pain or restriction of ROM. A 'Wait and see' policy is a first-line management, especially for those with multicentric extra-abdominal desmoids.

Mid-term results of MR-guided high-intensity focused ultrasound treatment for relapsing superficial desmoids

Purpose: Desmoids are locally infiltrative, nonmalignant soft tissue tumors. Surgery, radiation therapy, and chemotherapy have been the mainstay of treatment, but relapse is common and side effects can result in significant morbidity. MR-HIFU is increasingly recognized as an alternative treatment modality. We assessed the success rate of MR-HIFU for the treatment of extra-abdominal desmoids at our institute.Materials and methods: Five patients with relapsing desmoid tumors (three males, two females; age range 40–79 years) were treated using the Sonalleve system in an outpatient setting without general anesthesia. Changes in total tumor volumes were measured with a tumor tracking software. Adverse events were documented.Results: MR-HIFU was successful in all patients without severe side effects. Follow up ranged from 13 to 60 months. Three patients required more than one treatment session. In 3 patients with small lesions (mean = 9.7 mL), complete ablation was achieved with no evidence of viable tumor on follow up MRI at an average of 35.7 months, while in two patients with larger lesions (mean = 46 mL) the targeted tumor volumes decreased by 73% at 14 months. Skin injuries comprised first- and second-degree burns and were observed with short distance to skin (mean = 0.9 cm) and proximity to bone (i.e. ribs). Skin burns healed within weeks with topical treatment.Conclusion: MR-HIFU shows good mid-term result for extra-abdominal desmoids with complete response for small lesions and stabilization of larger lesions. MR-HIFU for desmoids can be performed under regional anesthesia/sedation as outpatients.

Desmoid Tumor: Rare Abdominal Wall Lump in a Multiparous Woman

ABSTRACT Background Desmoids are rare tumors. Abdominal wall desmoids are more common in women of reproductive age, especially postpartum women. Here we present a case of desmoid tumor in a 37-year-old multiparous woman, who came with the complaint of a slowly growing painless abdominal lump. Case report A 37-year-old multiparous female presented with the complaint of a gradually increasing, painless abdominal lump. On physical examination, a well-defined, firm, mobile mass was palpated in the suprapubic region. Ultrasound revealed a homogeneous hypoechoic lesion in the right anterolateral abdominal wall. Computed tomography (CT) of the abdomen showed a well-defined homogeneous mass in relation to the inferior aspect of right rectus abdominis muscle. These clinical and imaging features were highly suggestive of abdominal wall desmoid, which was confirmed on fine needle aspiration cytology and postoperative tumor histopathology. Discussion Desmoids are uncommon benign, locally aggressive fibrous lesions that have an insidious course. Conventionally, these are classified as abdominal desmoids (occurring in abdominal wall, mesentery, or retroperitoneum) and extra-abdominal desmoids (affecting shoulder girdle, trunk, lower extremities, etc.). The definitive diagnosis of desmoid has to be established on histopathology. Wide local excision remains the definitive treatment of abdominal wall desmoids. Radiation therapy, chemotherapy, and endocrine therapy are the other treatment options. How to cite this article Garg M, Prabhakar N, Prakash M, Dahiya D, Khandelwal N. Desmoid Tumor: Rare Abdominal Wall Lump in a Multiparous Woman. J Postgrad Med Edu Res 2018;52(1):31-33.

DESMOID TUMOR OF THE MEDIASTINUM: A 6-YEAR CLINICAL FOLLOW-UP AFTER THE COMBINED MODALITY TREATMENT: A CASE REPORT

Extra-abdominal desmoids are tumors with borderline biologic behavior and tendency to frequent local recurrence. The paper presents a case of successful treatment of this rare tumor with involvement of mediastinal structures. The combined modality treatment resulted in 6-year disease-free survival.

Aggressive Desmoplastic Fibromatosis - A Clinicians Dilemma Case Report and Review of Literature

Fibromatoses are a heterogeneous group of distinct entities which differ in biological behaviour, but arehistologically very similar. This group of fibrous tumor or tumor like lesions, present considerable difficulties in pathologic diagnosis. Aggressive fibromatosis (AF) of the oral or para-oral structures is a very uncommon finding and its intra-osseous component is even relatively unusual. Such lesions with their origin from within the bone are termed desmoplastic fibromatosis (DF). These lesions must be distinguished from other fibroblastic tumors of the head and neck such as benign fibrous histiocytoma (BFH), fibrosarcoma, nerve sheath tumors and tumors of muscular origin. The major challenge in dealing with lesions of fibromatosis is to avoid an overdiagnosis of fibrosarcoma or an underdiagnosis of reactive fibrosis.Problems of differential diagnosis concern a wide range of diseases and immunohistochemical analysis may be helpful in diagnosis. With respect to the patient's post-operative well-being and if periodic follow-ups are guaranteed, the tumor should be carefully resected with only narrow safety margins. A rare case of aggressive desmoplastic fibromatosis in a 12-year-old girl is presented in this article with emphasis on the need and challenges for diagnosing such lesions as they have to be differentiated from other soft tissue tumors which display borderline pathological features regarding benign or malignant behaviour. Synonyms listed for the same include extra-abdominal desmoids, extra-abdominal fibromatosis, desmoids tumor, aggressive fibromatosis, juvenile desmoids-type fibromatosis, infantile fibromatosis.

A to Z of Desmoid Tumors

The purpose of this article is to illustrate the common locations of desmoid tumors (deep fibromatosis), complications of intra- and extraabdominal desmoids, and treatment-related changes in their imaging appearance. Desmoids are locally aggressive fibrous tumors with a tendency to recur. Desmoids can be intraabdominal, in the abdominal wall, or extraabdominal. Complications, such as compression or invasion of adjacent structures, and abscess formation can occur. Treatment options include observation, local treatment (surgery, radiotherapy), or systemic therapy (conventional chemotherapy, molecular targeted agents).

Activity of Sorafenib against Desmoid Tumor/Deep Fibromatosis

Desmoid tumors (deep fibromatoses) are clonal connective tissue malignancies that do not metastasize, but have a significant risk of local recurrence, and are associated with morbidity and occasionally mortality. Responses of desmoid patients to sorafenib on an expanded access program led us to review our experience. After Institutional Review Board (IRB) approval, we reviewed data for 26 patients with desmoid tumors treated with sorafenib. Sorafenib was administered at 400 mg oral daily and adjusted for toxicity. Sorafenib was the first-line therapy in 11/26 patients and the remaining 15/26 had received a median of 2 prior lines of therapy. Twenty-three of 26 patients had shown evidence of progressive disease by imaging, whereas 3 patients had achieved maximum benefit or toxicity with chemotherapy. Sixteen of 22 (∼70%) patients reported significant improvement of symptoms. At a median of 6 months (2-29) of treatment, the best response evaluation criteria in solid tumors (RECIST) 1.1 response included 6/24 (25%) patients with partial response (PR), 17/24 (70%) with stable disease, and 1 with progression and death. Twelve of 13 (92%) patients evaluated by MRI had > 30% decrease in T2 signal intensity, an indirect metric for increased fibrosis and loss of cellularity. Eighty percent of patients with radiological benefit had extra-abdominal desmoids. Sorafenib is active against desmoid tumors. A prospective, randomized clinical trial of sorafenib against other active agents is warranted. Loss of MRI T2 signal may be a useful surrogate for defining responses, but requires validation by examination of tumor pathology.

Evaluation of management of desmoid tumours associated with familial adenomatous polyposis in Dutch patients

Background:The optimal treatment of desmoid tumours is controversial. We evaluated desmoid management in Dutch familial adenomatous polyposis (FAP) patients.Methods:Seventy-eight FAP patients with desmoids were identified from the Dutch Polyposis Registry. Data on desmoid morphology, management, and outcome were analysed retrospectively. Progression-free survival (PFS) rates and final outcome were compared for surgical vs non-surgical treatment, for intra-abdominal and extra-abdominal desmoids separately. Also, pharmacological treatment was evaluated for all desmoids.Results:Median follow-up was 8 years. For intra-abdominal desmoids (n=62), PFS rates at 10 years of follow-up were comparable after surgical and non-surgical treatment (33% and 49%, respectively, P=0.163). None of these desmoids could be removed entirely. Eventually, one fifth died from desmoid disease. Most extra-abdominal and abdominal wall desmoids were treated surgically with a PFS rate of 63% and no deaths from desmoid disease. Comparison between NSAID and anti-estrogen treatment showed comparable outcomes. Four of the 10 patients who received chemotherapy had stabilisation of tumour growth, all after doxorubicin combination therapy.Conclusion:For intra-abdominal desmoids, a conservative approach and surgery showed comparable outcomes. For extra-abdominal and abdominal wall desmoids, surgery seemed appropriate. Different pharmacological therapies showed comparable outcomes. If chemotherapy was given for progressively growing intra-abdominal desmoids, most favourable outcomes occurred after combinations including doxorubicin.

Extra‐abdominal desmoid tumors: A report of 234 cases

To report on the clinical presentation and outcome for 234 patients with extra-abdominal desmoids tumors. Since 1977, the authors have treated 234 patients with extra-abdominal desmoid tumors. The patients had an average age of 36.7 and 61% were female. The tumors arose adjacent to muscles or bones and the largest number were in the foot, shoulder thigh and calf. All of the patients were treated by primary surgery. Thirty-seven had additional radiation and eight had chemotherapy. Local recurrence occurred in 39 patients and 23% of the patients required additional surgery. Of great concern were 24 patients who developed multiple sites metachronously, which required further surgery and in many cases caused disability. None of the patients died of disease but 5 required amputations. The authors concluded that despite the benign nature of the disease, these patients are difficult to treat and the results are sometimes considerably less than optimal.

Prognostic factors for extra‐abdominal and abdominal wall desmoids: A 20‐year experience at a single institution

Previous reports even large studies discussing the prognosis of desmoids have included tumors from intra- and extra-abdominal sites as well as incomplete resection. The purpose of this study was to explore prognostic factors associated with the recurrence free survival (RFS) rate in surgically treated extra-abdominal and abdominal wall desmoids. A total of 198 consecutive desmoid patients were treated with surgery over a 20-year period at a single institution. Of these, 151 patients with extra-abdominal and abdominal wall tumors were retrospectively reviewed. One hundred thirteen patients were referred for the primary tumor and the other 38 for recurrent disease initially treated elsewhere. All patients underwent a macroscopically complete resection. The median follow-up interval was 102 months. Thirty-one patients (20.5%) had a local recurrence (LR). No patients died of the disease. The 5- and 10-year RFS was 79.7% and 78.5%, respectively. Admission status, gender, tumor size, margin status, location, and number, were predictors of LR in univariate analysis. Tumor size and margin status were independent prognostic factors in multivariate analysis. Positive margins were predictive of recurrence of primary disease, and also showed a trend for recurrent disease, which was not statistically significant. The selective use of adjuvant radiation did not show significant benefit over local control. Regardless of primary or recurrent disease, microscopically negative margins should always be the goal for extra-abdominal desmoids surgery, if no cosmetic defects or function demolition is encountered. Extra-abdominal desmoids deserve more attention and should be treated more aggressively, especially when leaving positive margins.

Sonographic Imaging of Abdominal and Extraabdominal Desmoids

To describe the sonographic imaging characteristics of abdominal and extraabdominal desmoids. We retrospectively investigated 12 histologically and pathologically proven abdominal and extraabdominal desmoids. Two radiologists with musculoskeletal sonography experience reviewed sonographic images for lesion location, size, echotexture, and vascularity with agreement by consensus. Desmoids were seen in 9 females and 3 males. They manifested as slowly growing masses. Nine lesions were intramuscular and 3 were found within the subcutaneous adipose tissue. A typical sonographic feature of all intramuscular desmoids was the spindle-shaped margin at the tumor ends when scanned along the long axis of the affected muscle. The desmoids arising from the fascia had an irregular shape. Tumor vascularity was rich in 6 cases and poor in 6 cases. A fibrillar pattern within the tumor was found in 75% of the cases. A spindle-shaped appearance is common in intramuscular desmoids. Hyperechoic areas and a fibrillar pattern within desmoids are also common sonographic features.

Efficacy of methotrexate + vinblastine in intra-abdominal desmoid (mesenteric aggressive fibromatosis): Retrospective analysis of 29 patients from a single institution

10567 Background: Desmoid tumors (DT) are rare neoplasms characterized by clonal proliferation of myofibroblasts, that do not metastasize but exhibit an infiltrative pattern, producing tissue destruction and significant functional impairment. Although sporadic desmoids are rare, these tumors are common in patients (pts) with familial adenomatous polyposis (FAP): 3.5 to 32% of the pts are diagnosed with diffuse mesenteric desmoid, which is the second reported lethal complication of FAP. The combination of methotrexate (MTX) + vinblastine (VNB) is known to be active in extraabdominal desmoids. Methods: The dataset of the Istituto Nazionale Tumori, Milan (1,115 Classical FAP) was analyzed. Overall, 167 (14.9%) were diagnosed with DT arising in FAP. 104/167 were females, and age ranged from 29 to 70 years. 96/167 pts received surgery. In this case series analysis, we retrospectively reviewed clinical efficacy of weekly MTX at the dose of 30 mg/m2 + VBL at the dose of 6 mg/m2 in 29 consecutive pts, all of whom but 2 have concluded their therapy. As an external control, we retrospectively evaluated also 43 pts treated with other approaches (hormone therapy, NSAIDs, etc.) in the same period. Tumor response was assessed by RECIST criteria after the first 2 months of treatment and then every other month. Results: As of December 2007, 21 pts (72%) had PR or SD exceeding 6 months. Of pts treated with other approaches, 23 (53%) are still on treatment with PR or SD exceeding 6 months. Overall, 32/167 pts died, 14 of intra-abdominal DT (8.4%), 10 of Colorectal cancer, 6 of extracolonic cancer, and 2 of other causes. Conclusions: The MTX and VBL regimen seems to active also in intra-abdominal DT, as shown in sporadic DT, and may be considered among the medical options available for the advanced stages of this disease. No significant financial relationships to disclose.

Regression of sporadic intra-abdominal desmoid tumour following administration of non-steroidal anti-inflammatory drug

BackgroundDesmoid tumours or fibromatoses are rare entities characterized by the benign proliferation of fibroblasts, which can be life-threatening due to their locally aggressive properties. Surgery is widely accepted as the first line of treatment for extra-abdominal desmoids; however, it is not recommended for intra-abdominal desmoids because of the high-risk of recurrence and difficulties with the operation. Here, we report on a patient with sporadic intra-abdominal desmoid tumours, who showed partial response following the intake of non-steroidal anti-inflammatory drugs.Case presentationA 73-year-old man presented with swelling and pain of the right leg. Computed tomography showed an abnormal multilocular soft-tissue mass (95 × 70 mm) in the right pelvis, which was revealed by biopsy to be a desmoid tumour. Immunohistochemical analysis showed that the tumour cells expressed vimentin, but not smooth-muscle actin, CD34, or desmin. Very few Ki-67-positive cells were found. Non-cytotoxic treatment with etodolac (200 mg/day) was chosen because of the patient's age, lack of bowel obstruction, and the likelihood of prostate cancer. Two years after the commencement of non-steroidal anti-inflammatory drug administration, computed tomography showed a decrease in tumour size (63 × 49 mm), and the disappearance of intratumoural septa.ConclusionOur case report suggests that non-steroidal anti-inflammatory drug treatment should be taken into consideration for use as first-line treatment in patients with sporadic intra-abdominal desmoid tumours.

Desmoid Tumors – a Characterization of Patients Seen at Mayo Clinic 1976–1999

Desmoid tumors occur with high frequency in individuals with Familial Adenomatous Polyposis (FAP). Because of this, individuals developing desmoid tumors may be referred for genetic risk assessment. Determining whether a person has a FAP-related desmoid tumor or a sporadic desmoid can be challenging. We sought to characterize the patients who were seen at our institution to determine if there were clinical differences in presentation between FAP-associated and sporadic desmoid tumors. We searched the Mayo Clinic-modified H-ICDA (Hospital adaptation of the International Classification of Diseases) diagnostic codes for all diagnoses of desmoid tumors in patients seen between 1976 and 1999. Charts were reviewed to determine accuracy of diagnosis, age when seen, gender, site of tumor, and presence of polyposis. A total of 454 patients (174 males and 280 females) met the search criterion. Of the 447 patients on whom all data was obtained, 70 had FAP and 377 had no evidence of FAP. The female/male ratio for FAP cases was 1.12 compared to female/male ratio of 1.71 for non-FAP cases. (P=0.17). Location of development of desmoid tumors was correlated with but not specific for distinguishing FAP from non-FAP desmoids. Abdominal desmoids comprised the majority of FAP desmoids and extra-abdominal desmoids comprised the majority of non-FAP desmoids (P<0.001) but age was not a discriminating factor. Using Bayesian analysis, we demonstrate how these findings can assist genetic professionals in their evaluation of patients with desmoid tumors by providing prior probabilities of FAP based upon clinical presentation.

Desmoplastic fibroma (desmoid) of the femur: 2 cases

Desmoplastic fibroma (extra-abdominal desmoid) was first identified as an independent nosological form in 1958 by H.L. Jaffe [6]. This tumor differs significantly in its course from the desmoid of the abdominal wall. It has a pronounced ability to infiltrate the surrounding tissues, there are frequent cases of tumor spread to the vessels and nerves. The disease usually affects soft tissues. Extra-abdominal desmoids often occur in the area of ​​the shoulder, chest wall, back, and scapula [1, 6]. Desmoplastic bone fibromas are extremely rare. So, R. Buhm et al. [5] described two cases of this tumor affecting the tibia. According to their data, by 1996 only a few dozen cases of bone lesions were presented in the literature. N.P. Petrovichev [3] described the case of femoral desmoid. In the book by S.T. Zatsepin "Saved surgery for bone tumors" [2] reports on operations on the forearm in two patients with recurrence of desmoplastic fibroma. Surgical interventions were accompanied by resection of the bones of the forearm. The observations are interesting, but in neither case are there any clinical or radiological data that could indicate damage to the bones of the forearm by desmoid, and the author himself does not indicate this. We did not find other publications on desmoplastic bone fibroma in the domestic literature. According to N.N. Petrovichev with reference to the work of H.J. Spjut, published in 1971, only 6 cases of femoral injury were described in the literature by that time.

Desmoid Fibroma: are We Ready to Avoid the Surgical Treatment?

Thirty years experience of treatment of soft tissue desmoid fibroma (Moscow Oncologic Institute) is presented. Efficacy of surgical treatment versus combined and radiation therapy was studied. The rate of relapse of extraabdominal desmoids after surgical treatment was 94%, after combined treatment with preoperative radiation therapy the relapse rate decreased up to 27.5% but after postoperative radiation therapy up to 53%. After radiation therapy the relapse rate was 15.7%. However radiation therapy has limitations related the necessity of massive tumor irradiation and application of high doses of irradiation that may cause postradiation affect of tissues. During subsequent search the original method of chemiotherapy (tamoxiphen, vinblastin, methotrecoat) was tested. This method allows to achieve the persistent remission in 81.3% of patients. Principles of therapeutic tactics in desmoid fibromas are formulated.

Extra-Abdominal Fibromatosis (Desmoid Tumor) Arising in the Infratemporal Fossa: A Case Report

Aggressive fibromatosis (or desmoid tumor) refers to a histologically benign but locally aggressive lesion arising from musculoaponeurotic structures in various anatomic sites. Extra-abdominal desmoids represent about one third of all desmoid tumors; of these only about 11 to 15% arise in the head and neck. Desmoid tumors arising in the infratemporal fossa are exceedingly rare; to our knowledge only one such tumor has been reported in the literature. We present a desmoid tumor arising in the infratemporal fossa with intracranial extension in a twenty-seven year old male and review the literature on this rare condition.

Clinicopathological and interphase cytogenetic analysis of desmoid tumours.

Recurrence of desmoid tumours is difficult to predict from only histological findings. In this study, immunohistochemistry for counting stromal blood vessels and proliferative activity, DNA flow cytometry, and interphase cytogenetic analysis of chromosome 8 by fluorescence in-situ hybridization (FISH) were performed to assess the correlation between their parameters and the recurrence of desmoid tumours. The cases examined included 16 extra-abdominal desmoid and eight abdominal desmoids, comprising 14 recurrent and 10 non-recurrent cases. Eleven (69%) of the 16 extra-abdominal desmoids and three (38%) of the eight abdominal desmoids recurred. Patients with recurrent lesions (mean age, 20 years) were younger than those with non-recurrent tumours (34 years). Histologically, tumours with hypervascular areas frequently recurred after surgery in comparison with those with hypovascularity. There was no significant correlation between tumour size, the labelling index of the proliferating cell nuclear antigen (PCNA) and the recurrence. In flow cytometric analysis, all the cases examined showed a diploid pattern. The FISH study revealed that the incidence of trisomy 8 was significantly higher in the recurrent (72.7%) than in the non-recurrent cases (12.5%). These results suggest that a subgroup of desmoid tumours at risk of recurrence may be hypervascular lesions associated with trisomy 8.

Soft-tissue tumors: diagnosis with Tc-99m (V) dimercaptosuccinic acid scintigraphy.

To assess the potential of technetium-99m (V) dimercaptosuccinic acid (DMSA) scintigraphy for diagnosis of soft-tissue tumors. Tc-99m (V) DMSA scintigraphy was performed in 76 patients with histologic proof of soft-tissue tumors. In 57 of these patients, gallium-67 citrate scintigraphy was performed within 2 weeks after Tc-99m (V) DMSA scintigraphy. Uptake of Tc-99m (V) DMSA was clearly detected in almost all sarcomas, metastatic carcinomas, highly recurrent benign tumors (ie, extra-abdominal desmoids and tenosynovial giant cell tumors), superficial and deep hemangiomas, and granulomatous soft-tissue lesions but was not found in other benign solid tumors of soft tissue. Uptake of Ga-67 citrate was clearly detected in all inflammatory lesions and metastatic carcinomas, eight of 14 sarcomas (57%), and two of 10 highly recurrent benign tumors (20%) but was not found in hemangiomas or benign soft-tissue tumors. Low-grade malignant and highly recurrent benign lesions, which often recur after surgery, were detected more accurately with Tc-99m (V) DMSA scintigraphy than with Ga-67 citrate scintigraphy.

MR imaging of extraabdominal desmoids: differentiation from other neoplasms.

A retrospective review of MR images of 36 patients with histologically proved extraabdominal desmoids was done to define the MR characteristics of these tumors and to determine if MR could be used to differentiate desmoids from other benign and malignant soft-tissue neoplasms. The desmoids evaluated included eight primary and 30 recurrent lesions. Our study was conducted in parallel with another study in which the MR appearance of 95 benign and malignant soft-tissue masses was evaluated, and the MR images of these masses were compared with our findings. The four desmoids from that study are included in our data. The signal intensity of the tumor on T1- and T2-weighted images was graded relative to the intensities of muscle and fat. Homogeneity, margin, neurovascular and bone involvement, and fibrosis (low-signal regions within the tumor on both T1- and T2-weighted images) were evaluated. On MR imaging, the desmoids showed inhomogeneous signal (97%), poor margination (89%), neurovascular involvement (58%), and bone involvement (37%). Fibrosis was present in 88% of primary desmoids and 90% of recurrent ones, and intermediate signal (greater than that of muscle and less than that of fat) was present in 75% and 50% of these, respectively. Our results show that the MR features of desmoids have characteristics that are commonly found in malignant tumors (inhomogeneous signal, poor margination, and neurovascular involvement). MR features of desmoids that distinguish them from malignant neoplasms are the presence of fibrosis and intermediate signal in the regions of the tumor.