External-beam radiotherapy for pediatric and young adult desmoid tumors

Update on musculoskeletal applications of magnetic resonance-guided focused ultrasound

Magnetic resonance-guided focused ultrasound (MRgFUS) is a noninvasive, incisionless, radiation-free technology used to ablate tissue deep within the body. This technique has gained increased popularity following FDA approval for treatment of pain related to bone metastases and limited approval for treatment of osteoid osteoma. MRgFUS delivers superior visualization of soft tissue targets in unlimited imaging planes and precision in targeting and delivery of thermal dose which is all provided during real-time monitoring using MR thermometry. This paper provides an overview of the common musculoskeletal applications of MRgFUS along with updates on clinical outcomes and discussion of future applications.

Primary intra‑abdominal desmoid fibromatosis associated with familial adenomatous polyposis: A case report

Desmoid fibromatosis (DF) is a clonal proliferative disorder of myofibroblasts, which arises, with a low incidence, in soft tissue, including within the abdomen. The incidence of DF is associated with familial adenomatous polyposis (FAP), and is more common following FAP surgery. It is rare for a patient to make his/her first visit to hospital due to DF symptoms associated with FAP. In the present report, a case of mesenteric DF associated with FAP is described. This case also had incomplete intestinal obstruction due to DF. By summarizing previous studies examining DF and FAP treatment, combined with the disease characteristics of this patient, the clinical treatment strategy for DF associated with FAP was explored.

Long-term result of 125 I seed brachytherapy for pediatric desmoid tumor in the head and neck

BACKGROUND

Desmoid tumor (DT) is rare and challenging, often affects the head and neck (HN) region in children, and its appropriate treatments are under-discussed. This study aimed to retrospectively evaluate the long-term effectiveness and safety of ¹²⁵ I seed brachytherapy for pediatric DT in HN.

PROCEDURE

Seven pediatric patients with a median age of three years who suffered from DT in HN treated with ¹²⁵ I brachytherapy from January 2008 to June 2018 were included. Among these, five underwent sole brachytherapy and the others combined with surgery under prescription doses ranging from 10,000 to 12,000 cGy. The rate of local control (LC), complete response (CR), and partial response (PR) was calculated after evaluation by radiological and pathological means. Radiation-associated toxicities were also evaluated.

RESULTS

The LC rate was 7/7 during the follow-up time ranging from 43 to 135 months and with a mean of 57 months. No recurrent lesion was found in the patients receiving surgery combined with brachytherapy. In patients treated with sole brachytherapy, the radiological PR rate and CR rate were 4/5 and 1/5, respectively. In those reaching radiological PR, 3/4 were pathological CR. Slight acute radiation-associated toxicities were observed in all patients, and no late or severe acute toxicity was observed.

CONCLUSION

¹²⁵ I brachytherapy is effective and safe in the management of pediatric DT in HN as the sole modality or combined with surgery in the long term.

The efficacy of low-power cumulative high-intensity focused ultrasound treatment for recurrent desmoid tumor

Background

Desmoid tumors are rare neoplasms that are locally invasive. However, optimal treatment strategies for recurrent desmoid tumors remain controversial. High‐intensity focused ultrasound (HIFU) has been reported as a noninvasive modality for treating recurrent desmoid tumors. However, its efficacy against massive desmoid tumors or those with complex anatomies remains unclear.

Methods

We developed a new therapeutic strategy called low‐power cumulative HIFU and applied it to treat recurrent desmoid tumors.

Results

We retrospectively collected data from 91 patients with recurrent desmoid tumors who underwent low‐power cumulative HIFU treatment after surgical treatment failure. The mean ablation proportion of the HIFU treatment was 69.5%, and the objective response rate was 47.3%. The 5‐year estimated progression‐free survival rate for these patients was 69.3%.

Conclusion

Low‐power cumulative HIFU treatment could achieve significant efficacy and long‐term control of recurrent desmoid tumors.

Focused Ultrasound for Pediatric Diseases

Focused ultrasound (FUS) is a noninvasive therapeutic technology with multiple pediatric clinical applications. The ability of focused ultrasound to target tissues deep in the body without exposing children to the morbidities associated with conventional surgery, interventional procedures, or radiation offers significant advantages. In 2021, there are 10 clinical pediatric focused ultrasound studies evaluating various musculoskeletal, oncologic, neurologic, and vascular diseases of which 8 are actively recruiting and 2 are completed. Pediatric musculoskeletal applications of FUS include treatment of osteoid osteoma and bone metastases using thermal ablation and high-intensity FUS. Pediatric oncologic applications of FUS include treatment of soft tissue tumors including desmoid tumors, malignant sarcomas, and neuroblastoma with high-intensity FUS ablation alone, or in combination with targeted chemotherapy delivery. Pediatric neurologic applications include treatment of benign tumors such as hypothalamic hamartomas with thermal ablation and malignant diffuse intrinsic pontine glioma with low-intensity FUS for blood brain barrier opening and targeted drug delivery. Additionally, low-intensity FUS can be used to treat seizures. Pediatric vascular applications of FUS include treatment of arteriovenous malformations and twin-twin transfusion syndrome using ablation and vascular occlusion. FUS treatment appears safe and efficacious in pediatric populations across many subspecialties. Although there are 7 Food and Drug Administration-approved indications for adult applications of FUS, the first Food and Drug Administration approval for pediatric patients with osteoid osteoma was obtained in 2020. This review summarizes the preclinical and clinical research on focused ultrasound of potential benefit to pediatric populations.

Musculoskeletal Applications of Magnetic Resonance-Guided Focused Ultrasound

Magnetic resonance-guided focused ultrasound (MRgFUS) is a novel noninvasive therapy that uses focused sound energy to thermally ablate focal pathology within the body. In the United States, MRgFUS is approved by the Food and Drug Administration for the treatment of uterine fibroids, palliation of painful bone metastases, and thalamotomy for the treatment of essential tremor. However, it has also demonstrated utility for the treatment of a wide range of additional musculoskeletal (MSK) conditions that currently are treated as off-label indications. Advantages of the technology include the lack of ionizing radiation, the completely noninvasive technique, and the precise targeting that offer unprecedented control of the delivery of the thermal dose, as well as real-time monitoring capability with MR thermometry. In this review, we describe the most common MSK applications of MRgFUS: palliation of bone metastases, treatment of osteoid osteomas, desmoid tumors, facet arthropathy, and other developing indications.

Rationale for the use of tyrosine kinase inhibitors in the treatment of paediatric desmoid-type fibromatosis

In children with desmoid-type fibromatosis (DTF) in whom disease progression occurs after an initial watch-and-wait strategy, prolonged low-dose chemotherapy using vinblastine and methotrexate (VBL-MTX) is currently the standard of care. These conventional drugs have been prospectively evaluated but their efficacy and safety profiles are limited, and alternative therapeutic options are therefore essential. Based on the results of clinical trials, the use of tyrosine kinase inhibitors (TKIs) in the treatment of DTF is currently considered only in adult patients. TKIs such as imatinib show superior therapeutic efficacy to VBL-MTX and tolerable short-term side effects for the treatment of adult DFT, supporting the concept of the use of TKIs for the treatment of paediatric DFT. Moreover, new-generation TKIs, such as pazopanib and sorafenib, have shown improved therapeutic efficacy compared to imatinib in adult non-comparative studies. A tolerable safety profile of TKI therapy in children with disease entities other than DTF, such as leukaemia, has been reported. However, the efficacy and, in particular, the long-term safety of TKIs, including childhood-specific aspects such as growth and fertility, for the treatment of children with DTF should be investigated prospectively, as DFT therapy requires long-term drug exposure.

The Role of Radiation Therapy for Symptomatic Desmoid Tumors

OPINION STATEMENT

Desmoid tumors have a variable clinical course that ranges from indolence or spontaneous regression to an aggressive pattern marked by local invasion. Up to half may remain stable or regress; watchful waiting is the preferred approach in the initial management of desmoid tumors. Symptomatic or progressive tumors or those that may affect adjacent critical structures require surgery, radiotherapy, or systemic therapy. Although radiotherapy effectively controls desmoid tumors in most cases, concerns regarding late toxicity exist. Definitive radiotherapy for macroscopic disease is indicated when a non-morbid complete surgical resection cannot be accomplished and provides similar control rates to surgery plus radiotherapy but avoids toxicity from combined-modality treatment (surgery and radiotherapy). Adjuvant radiotherapy can be considered for microscopically involved margins, particularly for recurrent cases or when a future recurrence may be challenging to treat. Large size, extremity site, and younger age are poor prognostic factors after radiotherapy. In the extremity, radiotherapy may have superior outcomes to surgery. Younger patients, especially children, are challenging to manage as they are at particular risk for late toxicity due to the number of potential years at risk. For patients under 20 years old, for whom a non-morbid complete resection is not possible, we recommend systemic therapy as the first line of treatment. Although the long-term efficacy of systemic therapy is unproven, this strategy allows additional time for growth and development prior to radiotherapy. In younger patients and those with axial desmoid tumors adjacent to critical organs, consideration should be given to using proton therapy as the dosimetric advantages may mitigate some of the toxicity associated with conventional radiotherapy.

Definitive radiation therapy in patients with unresectable desmoid tumors: a systematic review

Background

Desmoid tumors are rare soft tissue tumors. Wide local excision has been the standard surgical treatment for desmoid tumors. However, this procedure results in high local recurrence rates, so non-surgical treatments should be considered. The aim of this systematic review was to evaluate the effect of radiation therapy on patients with desmoid tumors, especially those with unresectable disease.

Methods

We evaluated studies published between 1 January 1990 and 31 August 2017 and cited in PubMed and Ichushi (in Japanese). All studies evaluating the effect of radiation therapy on desmoid tumors were included. Data regarding radiation dose, recurrence and adverse events were recorded.

Results

Among 218 identified studies, only 6 were finally included in this review. Local control was achieved in 253 of 317 patients with unresectable or unresected tumors who underwent definitive radiation therapy (the crude rate of local control was 79.8%). Toxicity was evaluated in patients who underwent definitive radiation therapy or surgery plus radiation therapy. One of the most common acute complications was skin toxicity. Frequent late complications of radiation therapy included fibrosis/contracture/joint stiffness, skin disorders, lymphedema and pain. Six patients developed secondary malignancies in the radiation field.

Conclusions

In patients treated unsuccessfully with surgery, watchful waiting and pharmacotherapy, radiation therapy may be an option as salvage therapy because of the high rate of local control. Because desmoid tumors frequently develop in young individuals, children and young patients who receive radiation therapy for the treatment of desmoid tumors should be followed up on a long-term basis with periodic monitoring for late radiation toxicities.

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.

The impact of technical parameters on ablation volume during MR-guided focused ultrasound of desmoid tumors

PURPOSE

Desmoid tumors are benign, locally aggressive soft tissue tumors derived from fibroblasts. Magnetic resonance-guided focused ultrasound (MRgFUS) is a safe and effective treatment for desmoid tumors. The purpose of this study was to retrospectively review the MRgFUS treatments of desmoid tumors at our institution to determine which technical treatment parameters contributed most significantly to the accumulation of thermal dose.

MATERIALS AND METHODS

The study protocol was approved by the local IRB. We retrospectively reviewed data from MRgFUS treatments performed in histologically-confirmed desmoid tumors, over a period of 18 months. Sonication parameter means were compared with ANOVA. Mixed effects and linear regression models were used to evaluate the relative contribution of different parameters to thermal dose volume.

RESULTS

Nine-hundred thirty-six sonications were reviewed in 13 treatments. Accumulated dose per sonication was greatest for elongated sonications (0.96 cc ± 0.90) compared to short (0.88 ± 0.93 cc) and nominal (0.55 ± 0.70 cc) sonications, p < .001. 65.2% of short sonications resulted in high percentage ablations, compared to 46.0% of nominal and 35.1% of elongated sonications. Standardized beta coefficients (anticipated increased volume in cc per unit) for power, duration, energy and average temperature were 0.006, 0.057, 0.00035 and 0.03, p < .001. Regarding dose efficacy, dose area contributed the greatest to this variability - 50.7% (45.5-54.8%), followed by distance - 16.6% (12.9-20.0%).

CONCLUSIONS

A variety of sonication parameters significantly contributed to thermal ablation volume following MRgFUS of desmoid tumors, in reproducible patterns. This work can serve as the basis for future models working toward improved planning for MRgFUS treatments.

Optimal radiotherapy strategy for primary or recurrent fibromatosis and long-term results

Purpose

Although locally invasive or recurrent fibromatosis is primarily treated with surgery, radiotherapy (RT) produces local control for recurrent/unresectable tumors or those with positive surgical margins. Herein, we describe our updated institutional experience with RT to treat fibromatosis.

Methods

Forty-seven patients with fibromatosis received RT between 1990 and 2015, and were followed for ≥12 months. Eight patients received RT for gross tumors, and 39 received postoperative RT after single/multiple prior surgeries. A median dose of 54 Gy was prescribed for definitive RT; 48.6, 50.4, and 54 Gy were prescribed for R0, R1, and R2 resected tumors, respectively. Recurrences were classified as in-field, marginal, or out-field. Prognostic factors were also evaluated.

Results

Seven recurrences were noted, including 2 in-field, 4 marginal, and 1 out-field, after a median follow-up of 60 months. In-field recurrences occurred in 1 patient who received 40.5 Gy of salvage RT after postoperative recurrence and another who received 45 Gy for R1 resection after multiple prior operations. All marginal failures were due to insufficient clinical target volume (CTV) margins regardless of dose (3 with 45 Gy and 1 with 54 Gy). On multivariate analysis, a CTV margin ≥5 cm and dose >45 Gy were significant predictors of non-recurrence (p = 0.039 and 0.049, respectively). Subgroup analysis showed that patients with both an CTV margin ≥5 cm and a dose >45 Gy showed a favorable outcome.

Conclusions

RT is a valuable option for treating aggressive fibromatosis; doses ≥45 Gy and a large field produce optimal results. For in-field control, a higher dose is more necessary for gross residual tumors than for totally excised lesions.

Aggressive fibromatosis in the infratemporal fossa presenting as trismus: a case report

Background

Here we report a very rare entity of an infratemporal region aggressive fibromatosis in a 23-year-old Tharu man who had presented with the symptoms of painless but progressive trismus.

Case presentation

We describe a case of aggressive fibromatosis in a 23-year-old Tharu man. Radiological imaging as well as an immunohistochemistry panel from a biopsy indicated a diagnosis of an aggressive fibromatosis. Since there was no aggravation in his trismus following surgery and because of his poor socioeconomic status, he was advised to attend regular follow-up visits without any adjuvant therapy.

Conclusions

This case report adds to the notion of keeping the differential diagnosis of an aggressive fibromatosis in all patients presenting with progressive but painless trismus. The characteristic imaging findings as well an immunohistochemistry panel will help us clinch the correct diagnosis.

How to Perform a Routine Cryoablation Under MRI Guidance

In the last decade, the spectrum of interventional magnetic resonance imaging (MRI)-guided procedures, including percutaneous ablation, has substantially grown, and among the available MRI-compatible ablative techniques, cryoablation is progressively gaining a predominant position.The aim of the present narrative review is to discuss the technical requirements necessary to perform a percutaneous MRI-guided cryoablation in a closed-bore machine; to highlight the relative advantages and drawbacks; and to briefly summarize the results available in the literature.

Borderline Sarcomas and Smooth Muscle Tumours of Uncertain Malignant Potential

Borderline sarcomas and smooth muscle tumours of uncertain malignant potential (STUMP) have an unpredictable clinical behaviour with frequent local recurrences and rarely, metastases. We review the current management of common subtypes of borderline sarcomas and STUMP.

MRgFUS for desmoid tumors within the thigh: early clinical experiences

BACKGROUND

Desmoid tumors are benign but locally aggressive non-malignant tumors derived from fibroblasts. Surgery, chemotherapy, and radiation therapy have been the mainstay of treatment, but recurrence is common and side effects can result in significant morbidity. In this case series, we highlight our experiences performing treatments in the thigh, including strategies for optimizing ablation size and safety.

CASE PRESENTATION

Since December 2014, 14 magnetic resonance-guided focused ultrasound (MRgFUS) treatments for desmoid tumors were performed at our institution in seven patients. Nine of these treatments were completed in three patients with large tumors within the posterior thigh. The first was a 7-year-old boy who had previously been treated with surgical resection, intra-operative radiation, along with courses of vinblastine/methotrexate and sorafenib. Pretreatment tumor volume was 770 cm³ with 75% non-enhancing volume following the initial treatment. The first treatment was complicated by a third-degree far-field skin burn. Enhanced safety measures were developed to protect the far-field skin. The patient had four subsequent treatments over 14 months, without complication, with non-perfused volume of 85% on current imaging. The second patient was a 21-year-old woman who had previously taken sulindac and celecoxib but had no other therapy. Pretreatment tumor volume was 740 cm³. The lateral decubitus position was used to minimize the amount of energy through the sciatic nerve. The first treatment resulted in a relatively low non-perfused volume of 30%. A follow-up treatment resulted in 75-80% ablation of the target. The third patient was a 14-year-old girl with no prior treatment. Pretreatment tumor volume was approximately 440 cm³. The sciatic nerve was encased by the anteromedial portion of the mass. A lateral decubitus position and enhanced safety measures were again used. The first treatment resulted in a relatively low non-perfused volume of 30%, likely related to low energies. The second treatment resulted in 70-80% ablation.

CONCLUSIONS

MRgFUS is an effective treatment for desmoid tumors of the thigh with a favorable side effect profile, allowing for repeated treatments if necessary. Ablation size and safety can be improved with far-field coupling devices, careful patient positioning, and optimized sonication planning.

Efficacy of vinorelbine combined with low-dose methotrexate for treatment of inoperable desmoid tumor and prognostic factor analysis

Objective

To assess the efficacy of conservative chemotherapy for inoperable desmoid tumor (DT) and analyze the prognostic factors.

Methods

From November 2008 to April 2016, 71 patients of inoperable DT were treated with vinorelbine and low-dose methotrexate in the Department of Bone and Soft Tissue Tumors, Peking University Cancer Hospital & Institute, and enrolled in this retrospective study. The chemotherapy duration is one year. The efficacy of chemotherapy and the prognosis were observed.

Results

Of the 71 patients, 55% were female. Age of onset varied from 1 to 47 years, and the median age was 14 years. Only 11 (15.5%) cases suffered primary tumor. The distribution of the site of tumors was: 31 (43.7%) in the trunk, 36 (50.7%) in the limbs, and 4 (5.6%) in the peritoneal and pelvic cavity. The size of tumor (the maximum diameter) differed from 2 to 37 cm with a mean of 9.3 cm. The median follow-up duration was 28 (range, 6-87) months. Common side effects included: nausea and vomiting, liver injury, bone marrow suppression and oral ulcers. When the chemotherapy finished, 1 (1.4%) case achieved complete response, 24 (33.8%) achieved partial response, 37 (52.1%) achieved stable disease and 9 (12.7%) had progressive disease. The overall response rate was 87.3%. The progression-free survival (PFS) of the participants were from 6 to 87 months, and the 2-, 3- and 5-year PFS was 79.9%, 68.4% and 36.3%, respectively. No significant difference was identified in PFS in subgroups of gender, age of onset, age of chemotherapy, tumor site and tumor size.

Conclusions

For recurrent, inoperable and progressive DT, enough course of chemotherapy with vinorelbine combined with low-dose methotrexate was an optional choice for local control.

Desmoid tumours of the head and neck in children: Review of management

OBJECTIVE

Desmoid tumours of the head and neck in children are rare, local invasive and potentially fatal tumours. The purpose of this review is to discuss the management of these tumours in the light of a case series and a review of the literature.

MATERIAL AND METHODS

This retrospective study summarised the medical data of children treated for desmoid tumours of the head and neck between 1976 and 2014.

RESULTS

Five of the 6 children were treated by radical surgical resection, with positive surgical margins (R1) in 2 cases, followed by recurrence requiring further resection. One child with a very advanced lesion was treated by weekly methotrexate and vinorelbine chemotherapy for 18months, allowing 93% reduction of tumour volume without recurrence.

CONCLUSIONS

Desmoid tumours of the head and neck in children are more aggressive than their adult counterparts and are associated with high morbidity and mortality and a high recurrence rate. CT and MRI imaging assessment should preferably be performed before biopsy. External beam radiotherapy must be avoided in children as it is less effective than in adults, and is responsible for long-term cosmetic and functional sequelae and even a risk of second tumours. Treatment is surgical whenever radical resection is possible. In patients presenting an excessive risk of morbidity and mortality, chemotherapy devoid of long-term adverse effects (such as methotrexate in combination with a Vinca alkaloid) can be proposed. Long-term follow-up must be ensured due to the risk of recurrence.

Recurrent giant cranial desmoid tumor in a 3-year-old boy with familial adenomatous polyposis requiring bifrontoparietal cranioplasty: case report

Desmoid tumors, also known as aggressive fibromatosis, are locally infiltrating musculoaponeurotic neoplasms arising in connective tissues. Desmoid tumors may be associated with familial adenomatous polyposis (FAP), a genetic disorder that presents with hundreds to thousands of precancerous colorectal polyps. The authors report the case of an 18-month-old boy who underwent resection of a right temporal desmoid tumor (initially diagnosed as cranial fasciitis) and developed a bilateral frontoparietal calvarial desmoid tumor 2 years later. The patient underwent gross-total resection of the tumor that required a large cranioplasty. He was subsequently diagnosed with FAP. The patient has been without tumor recurrence for 9 years afterwards and has not required revision of his cranioplasty. This is the first report describing a recurrent cranial desmoid tumor in a pediatric patient with FAP. The authors believe, however, that some of the cases previously reported as cranial fasciitis are likely desmoid tumors pathobiologically and genetically.

Desmoid-type fibromatosis of the head and neck in children: a case report and review of the literature

Background

Desmoid-type fibromatosis is defined as an intermediate tumor that rarely occurs in the head and neck of children. There is no doubt as to the value of complete surgical excision for desmoid-type fibromatosis. However, in pediatric patients, surgeons may often be concerned about making a wide excision because of the potential for functional morbidity. Some studies have reported a lack of correlation between margin status and recurrence. Therefore, we discussed our findings with a focus on the state of surgical margins.

Case presentation

We report an unusual case of a 9-month-old Japanese girl who prior to presenting at our hospital underwent debulking surgery twice with chemotherapy for desmoid-type fibromatosis of the tongue at another hospital. We performed a partial glossectomy and simultaneous reconstruction with local flap and achieved microscopic complete resection. We also reviewed available literature of pediatric desmoid-type fibromatosis in the head and neck.

Conclusions

We described successful treatment for the refractory case of pediatric desmoid-type fibromatosis. The review results showed that some microscopic incomplete resections of tumors in pediatric patients with desmoid-type fibromatosis tended to be acceptable with surgical treatment.

Magnetic resonance-guided focused ultrasound treatment of extra-abdominal desmoid tumors: a retrospective multicenter study

OBJECTIVES

To assess the feasibility, safety and preliminary efficacy of magnetic resonance-guided focused ultrasound (MRgFUS) for the treatment of extra-abdominal desmoid tumours.

METHODS

Fifteen patients with desmoid fibromatosis (six males, nine females; age range, 7-66 years) were treated with MRgFUS, with seven patients requiring multiple treatments (25 total treatments). Changes in viable and total tumour volumes were measured after treatment. Efficacy was evaluated using an exact one-sided Wilcoxon test to determine if the median reduction in viable tumour measured immediately after initial treatment exceeded a threshold of 50 % of the targeted volume. Median decrease after treatment of at least two points in numerical rating scale (NRS) worst and average pain scores was tested with an exact one-sided Wilcoxon test. Adverse events were recorded.

RESULTS

After initial MRgFUS treatment, median viable targeted tumour volume decreased 63 %, significantly beyond our efficacy threshold (P = 0.0013). Median viable total tumour volume decreased (105 mL [interquartile range {IQR}, 217 mL] to 54 mL [IQR, 92 mL]) and pain improved (worst scores, 7.5 ± 1.9 vs 2.7 ± 2.6, P = 0.027; average scores, 6 ± 2.3 vs 1.3 ± 2, P = 0.021). Skin burn was the most common complication.

CONCLUSIONS

MRgFUS significantly and durably reduced viable tumour volume and pain in this series of 15 patients with extra-abdominal desmoid fibromatosis.

KEY POINTS

• Retrospective four-centre study shows MRgFUS safely and effectively treats extra-abdominal desmoid tumours • This non-invasive procedure can eradicate viable tumour in some cases • Alternatively, MRgFUS can provide durable control of tumour growth through repeated treatments • Compared to surgery or radiation, MRgFUS has relatively mild side effects.

The Role of Radiotherapy in the Treatment of Primary or Recurrent Desmoid Tumors and Long-Term Results

BACKGROUND

Desmoid tumors are uncommon and benign mesenchymal neoplasms. The optimal treatment of patients with desmoid tumors is still controversial. Surgery is the primary treatment for locally invasive or recurrent desmoid tumors. Also, radiotherapy is a treatment option for patients at high risk for local failure such as those with positive margins or recurrent and unresectable tumors.

AIMS

To report our institutional experience and long-term results of patients with desmoid tumors who received radiotherapy.

STUDY DESIGN

Retrospective cross-sectional study.

METHODS

Between 1980 and 2009, 20 patients who received radiotherapy (RT) in our institution were analyzed. The majority of patients (80%) were referred with a recurrent tumor after previous surgery. Thirteen patients underwent marginal resection, 4 had wide local excision and 3 patients had only biopsy. Resection margin was positive in 15 (75%) patients. All patients received radiation therapy. The median prescribed dose was 60 Gy. Five patients received less than 54 Gy.

RESULTS

The median follow-up time was 77.5 months (28-283 months). Nine patients developed local recurrence after RT. Seven local failures (78%) were in field. Time to local recurrence ranged from 3-165 months (median 33 months). The 2-5 year local control (LC) rates were 80% and 69%, respectively. On univariate analysis, the 5 year local control rate was significantly better in the patients treated with ≥54 Gy than in patients who received <54 Gy (p=0.023). The most common acute side effect was grade 1-2 skin toxicity. As a late side effect of radiotherapy, soft tissue fibrosis was detected in 10 patients and lymphangitis was seen in 1 patient. One patient developed radiation-induced sarcoma.

CONCLUSION

According to our results, radiotherapy is especially effective in recurrent disease and provides a high local control rate in the patients received more than 54 Gy.

Extra-abdominal desmoid fibromatosis: A review of management, current guidance and unanswered questions

Extra abdominal desmoid fibromatosis is a complex condition with many recognised treatments including active observation, hormonal therapy, chemotherapy, radiotherapy and surgical resection. There is large variation in the natural history of individual desmoid tumours, with some cases progressing aggressively and others regressing spontaneously when observed alone. This combined with an absence of accurate clinical predictors of a desmoid tumour's behaviour has led to difficulties in identifying which patients would benefit most from aggressive treatment, and which could be adequately managed with a policy of active observation alone. This review explores the aetiology and common presentation of extra-abdominal desmoid fibromatosis including the condition's histopathological, clinical and radiological characteristics. The current evidence for potential predictors of desmoid tumour behaviour is also reviewed, along with the indications and evidence for the multitude of treatments available. We also summarise the published guidelines that are currently available for oncologists and surgeons managing extra-abdominal desmoid fibromatosis, and highlight some of the unanswered questions that need to be addressed to optimise the management of this condition.

Reconstruction of Desmoid Tumors: Case Series and Systematic Review

BACKGROUND

Desmoid tumors (DT) represent a group of rare, distinct lesions. There are few published studies examining outcomes and safety of complex reconstruction after DT resection.

METHODS

A retrospective review identified 39 patients who underwent surgical treatment of DT at St. Jude Children's Research Hospital over a 12-year period. A systematic review of the literature identified 17 further studies for inclusion. Treatment characteristics were analyzed.

RESULT

Thirty-nine patients were treated during the study period, with a total number of 67 resections. Median age was 12.2 years; 49% of patients were male, and 51% were female. Median tumor size was 9.8 cm. DT most commonly arose in the extremities (40%), thorax (23%), head and neck (21%), and trunk (16%). One- and 5-year recurrence-free survival were 97.1% and 73.1%, respectively. The majority of defects were closed primarily, with the exception of head and neck defects. Long-term outcomes were good for chest, abdomen, and upper extremity defects, but were problematic for head and neck, breast, and lower extremity defects. There were no recurrences at the site of flap harvest in either the study population or in reviewed studies.

CONCLUSION

For patients with DT, surgical extirpation should not come at the expense of functional preservation, as overall survival is excellent. However, specific defects, including those of the lower extremity, breast, and head and neck, will benefit from improved techniques for resection and reconstruction.

Treatment and follow-up strategies in desmoid tumours: a practice guideline

OBJECTIVES

We set out to determine the optimal treatment options-surgery, radiation therapy (rt), systemic therapy, or any combinations thereof-for patients with desmoid tumours once the decision to undergo active treatment has been made (that is, monitoring and observation have been determined to be inadequate).provide clinical-expert consensus opinions on follow-up strategies in patients with desmoid tumours after primary interventional management.

METHODS

This guideline was developed by Cancer Care Ontario's Program in Evidence-Based Care and the Sarcoma Disease Site Group. The medline, embase, and Cochrane Library databases, main guideline Web sites, and abstracts of relevant annual meetings (1990 to September 2012) were searched. Internal and external reviews were conducted, with final approval by the Program in Evidence-Based Care and the Sarcoma Disease Site Group.

RECOMMENDATIONS TREATMENTS

Surgery with or without rt can be a reasonable treatment option for patients with desmoid tumours whose surgical morbidity is deemed to be low.The decision about whether rt should be offered in conjunction with surgery should be made by clinicians and patients after weighing the potential benefit of improved local control against the potential harms and toxicity associated with rt.Depending on individual patient preferences, systemic therapy alone or rt alone might also be reasonable treatment options, regardless of whether the desmoid umours are deemed to be resectable.

RECOMMENDATIONS FOLLOW-UP STRATEGIES

Undergo evaluation for rehabilitation (occupational therapy or physical therapy, or both).Continue with rehabilitation until maximal function is achieved.Undergo history and physical examinations with appropriate imaging every 3-6 months for 2-3 years, and then annually.

A systematic review of active treatment options in patients with desmoid tumours

INTRODUCTION

We conducted a systematic review to determine the optimal treatment options in patients with desmoid tumours who have declined observational management.

METHODS

A search was conducted of the medline and embase databases (1990 to September 2012), the Cochrane Library, and relevant guideline Web sites and conference materials.

RESULTS

One systematic review and forty-six studies met the preplanned study selection criteria; data from twenty-eight articles were extracted and analyzed. For local control, three studies reported a statistically significant difference in favour of surgery plus radiotherapy (rt) compared with surgery alone, and one study did not; two studies reported the lack of a statistical difference between surgery plus rt and rt alone in maintaining local control. Multivariate risk factors for local recurrence included positive surgical margins and young patient age. Single-agent imatinib led to a progression-free survival rate of 55% at 2 years and 58% at 3 years. Methotrexate plus vinblastine led to a progression-free survival rate of 67% at 10 years. Significant toxicities were reported for all treatment modalities, including surgical morbidity, and rt- and chemotherapy-related toxicities.

CONCLUSIONS

In patients who have declined observational management, the local control rate was higher with surgery plus rt than with surgery alone. However, the additional rt-related complications should be considered in treatment decision-making. Surgery, rt, and systemic therapy are all reasonable treatment options for patients with desmoid tumours.

Surgical outcome of desmoid tumors: adjuvant radiotherapy delayed the recurrence, but did not affect long-term outcomes

BACKGROUND

We retrospectively reviewed the outcomes of desmoid tumor (DT) patients treated by surgical excision.

METHODS

Among 155 consecutive patients, 119 patients satisfied our inclusion criteria. The mean follow-up duration was 82 months. Age, gender, location, size, depth, resection margin, adjuvant radiotherapy, and excision history were analyzed for the outcomes.

RESULTS

The recurrence-free survival (RFS) rates were 75% at 5 years and 72% at 10 years. Twenty-seven (93.1%) out of 29 recurrences were detected within 5 years. In multivariate analysis, positive resection margin and excision history were independently associated with the RFS. In the comparison between the propensity score matched groups, adjuvant radiotherapy was not significantly associated with the RFS. The mean time interval from surgery to recurrence was 30.0 ± 28.7 months (median, 20 months; range, 4-123 months). This interval was significantly longer for patients who received adjuvant radiotherapy than for those who received surgical resection only, both in all recurrences and in recurrences in matched cases.

CONCLUSIONS

Surgical excision appears to be a reliable treatment option for DTs. However, positive outcomes require a clear resection margin. Adjuvant radiotherapy may delay the recurrence of the tumor, although it seems to have no effect on the ultimate relapse rate.

Desmoid fibromatosis in children and adolescents: a conservative approach to management

PURPOSE

Desmoid fibromatosis is associated with frequent recurrence and significant morbidity, but no metastases. To examine the impact of initial non-operative management on event-free survival (EFS) in children, we reviewed our institutional experience with this tumor.

METHODS

We retrospectively reviewed our institutional database for pediatric cases of desmoid fibromatosis treated between 1970 and 2010. Survival was analyzed using the Kaplan-Meier method and log-rank test.

RESULTS

Ninety-three patients were identified, with a median follow-up of 6 years. Median age at diagnosis was 16 years. Forty-seven patients presented with primary tumors, and forty-six had recurrent or progressing disease. Five-year OS was 100%, and 5-year EFS was 31.8%, with a median time to event of 1.48 years. There was no significant difference in 5-year EFS between patients who were managed expectantly and those who initially received treatment (21% versus 34%, P=.09). Sex, race, history of trauma, or familial adenomatous polyposis, multifocality, tumor size, tumor location, and resection status did not correlate with EFS.

CONCLUSION

Our findings support a conservative initial approach in the management of desmoid fibromatosis. In patients at risk for morbid procedures, upfront resection should be reserved for select tumors that demonstrate aggressive growth or cause serious symptoms.

Proton therapy versus photon radiation therapy for the management of a recurrent desmoid tumor of the right flank: a case report

Desmoid tumors are benign mesenchymal tumors with a strong tendency for local recurrence after surgery. Radiotherapy improves local control following incomplete resection, but nearby organs at risk may limit the dose to the target volume. The patient in this report presented with a recurrent desmoid tumor of the right flank and underwent surgery with microscopically positive margins. Particular problems presented in this case included that the tumor bed was situated in close proximity to the liver and the right kidney and that the right kidney was responsible for 65% of the patient's renal function. Intensity-modulated radiation therapy plans delivering 54 Gy necessarily exposed the right kidney to a V18 of 98% and the liver to a V30 of 55%. Proton therapy plans significantly reduced the right kidney V18 to 32% and the liver V30 to 28%. In light of this, the proton plan was utilized for treatment of this patient. Proton therapy was tolerated without gastrointestinal discomfort or other complaints. Twenty-four months after initiation of proton therapy, the patient is without clinical or radiographic evidence of disease recurrence. In this setting, the improved dose distribution associated with proton therapy allowed for curative treatment of a patient who arguably could not have been safely treated with intensity-modulated radiation therapy or other methods of conventional radiotherapy.

Extra-abdominal desmoid tumours: a review of the literature

Extra-abdominal desmoid lesions, otherwise known as aggressive fibromatosis, are slow-growing benign lesions which may be encountered in clinical practice. Recent controversies exist regarding their optimal treatment. Given their benign nature, is major debulking surgery justified, or is it worth administering chemotherapy for a disease process which unusually defies common teaching and responds to such medications? We present a literature review of this particular pathology discussing the aetiology, clinical presentation, and various current controversies in the treatment options.

Desmoid fibromatosis in pediatric patients: management based on a retrospective analysis of 59 patients and a review of the literature

Background. Only limited data are available concerning desmoid tumor in children. Methods. Fifty-nine children and adolescents with desmoid tumor treated in 2 French cancer centers with a very long followup were retrospectively reviewed. Results. Median age was 6 years (range, 0-15). Tumors mainly involved the limbs (42%). Five cases occurred in a context of genetic disorder. Surgery was first-line treatment in 80% of cases. Resection was microscopically complete in 3 patients (pts), with a microscopic residue in 19 pts and a macroscopic residue in 35 cases. Various adjuvant therapies were used. Overall response to all systemic therapies was 33%. Thirty-eight patients developed one or more recurrences or progressions. After a median followup of 8.5 years, 34 patients were alive in complete remission (CR), including 16 first CR. Seven patients died, 6 from refractory disease and 1 from colorectal carcinoma in a genetic context. Ten-year progression-free survival (PFS) and overall survival were 31% and 88%, respectively. In univariate analysis, age less than 10 years and head-neck site were favorable prognostic factors for PFS. Conclusions. When surgery is required, surgical margins must be negative. Low-dose chemotherapy can be proposed as adjuvant therapy. Prospective trials must be developed to evaluate long-term response and side effects.

Desmoid tumors in the pediatric population

Desmoid tumors are benign soft tissue tumors associated with locally aggressive growth and high rates of morbidity, but they do not metastasize via lymphatic or hematogenous routes. While most of the data on desmoid tumors originates in the adult literature, many of the findings have been applied to the management of pediatric patients. This article discusses the epidemiology, etiology, clinical presentation, pathology, and treatment of this rare tumor in the pediatric population and includes a literature review of the most recent large series of pediatric patients with desmoid tumors.