Evolution of Initial Treatment for Desmoid Tumors.

INTRODUCTION: Desmoid tumors (DTs) are rare, fibroblastic cell proliferations that can exhibit locally aggressive behavior but lack metastatic potential. Initial management has traditionally involved upfront resection; however, contemporary guidelines and expert panels have increasingly advocated for prioritizing active surveillance strategies. METHODS: A single-institution, retrospective chart review identified all patients diagnosed with a primary DT at any site from 2007 to 2020. The primary outcome was the initial management strategy over time. Secondary outcomes included treatment-free survival (TFS) and time to treatment (TTT) for those undergoing active surveillance, as well as recurrence-free survival (RFS) and time to recurrence for those undergoing resection. RESULTS: Overall, 103 patients were included, with 68% female and a median follow-up of 44 months [24-74]. The most common tumor locations included the abdominal wall (27%), intra-abdominal/mesenteric (25%), chest wall (19%), and extremity (10%). Initial management included resection (60%), systemic therapy (20%), active surveillance (18%), and cryoablation (2%). Rates of surgical resection significantly decreased (p < 0.001) over time, from 69.6% prior to 2018 to 29.2% after 2018. For those treated with upfront resection, 5-year RFS was 41.2%, and for patients undergoing initial active surveillance, TFS was 66.7% at 2 years, with a median TTT of 4 months [4-10]. CONCLUSIONS: This single-institution cohort at a tertiary medical center spanning over a decade demonstrates the transition to active surveillance for initial management of DTs, and highlights salient metrics in the era of surveillance. This trend mirrors recommended treatment strategies by expert panels and consensus guidelines.

MR-guided focused ultrasound therapy of extra-abdominal desmoid tumors: a multicenter retrospective study of 105 patients.

OBJECTIVE: To assess the safety and efficacy of magnetic resonance-guided focused ultrasound (MRgFUS) for the treatment extra-abdominal desmoids. METHODS: A total of 105 patients with desmoid fibromatosis (79 females, 26 males; 35 ± 14 years) were treated with MRgFUS between 2011 and 2021 in three centers. Total and viable tumors were evaluated per patient at last follow-up after treatment. Response and progression-free survival (PFS) were assessed with (modified) response evaluation criteria in solid tumors (RECIST v.1.1 and mRECIST). Change in Numerical Rating Scale (NRS) pain and 36-item Short Form Health Survey (SF-36) scores were compared. Treatment-related adverse events were recorded. RESULTS: The median initial tumor volume was 114 mL (IQR 314 mL). After MRgFUS, median total and viable tumor volume decreased to 51 mL (95% CI: 30-71 mL, n = 101, p < 0.0001) and 29 mL (95% CI: 17-57 mL, n = 88, p < 0.0001), respectively, at last follow-up (median: 15 months, 95% CI: 11-20 months). Based on total tumor measurements (RECIST), 86% (95% CI: 75-93%) had at least stable disease or better at last follow-up, but 50% (95% CI: 38-62%) of remaining viable nodules (mRECIST) progressed within the tumor. Median PFS was reached at 17 and 13 months for total and viable tumors, respectively. NRS decreased from 6 (IQR 3) to 3 (IQR 4) (p < 0.001). SF-36 scores improved (physical health (41 (IQR 15) to 46 (IQR 12); p = 0.05, and mental health (49 (IQR 17) to 53 (IQR 9); p = 0.02)). Complications occurred in 36%, most commonly 1st/2nd degree skin burns. CONCLUSION: MRgFUS reduced tumor volume, reduced pain, and improved quality of life in this series of 105 patients with extra-abdominal desmoid fibromatosis. CLINICAL RELEVANCE STATEMENT: Imaging-guided ablation is being increasingly used as an alternative to surgery, radiation, and medical therapy for the treatment of desmoid fibromatosis. MR-guided high-intensity focused ultrasound is an incisionless ablation technique that can be used to reduce tumor burden effectively and safely. KEY POINTS: • Desmoid fibromatosis was treated with MR-guided high-intensity focused ultrasound in 105 patients. • MR-guided focused ultrasound ablation reduced tumor volume and pain and improved quality of life. • MR-guided focused ultrasound is a treatment option for patients with extra-abdominal desmoid tumors.

Desmoid Tumors: Current Perspective and Treatment.

OPINION STATEMENT: Desmoid tumors are rare tumors with a tendency to infiltrate locally. The lack of a standard treatment approach makes choosing the most appropriate treatment for patients challenging. Most experts recommend watchful observation for asymptomatic patients as spontaneous regression of tumor is observed in up to 20% of patients. Upfront resection of the desmoid tumor has fallen out of favor due to high morbidity and high relapse rates associated with the tumor. Systemic therapy has evolved over several decades. Where chemotherapy, hormonal therapy, and non-steroidal anti-inflammatory drugs were used over the last several decades, tyrosine kinase inhibitors came to the forefront within the last decade. Most recently, gamma-secretase inhibitors have shown significant clinical benefit in patients with desmoid tumors, bringing forth an entirely new mechanistic approach. Several Wnt pathway inhibitors are also under development. Invasive approaches like cryoablation have also shown clinical benefit in patients with extra-abdominal desmoid tumors in recent years. The recent approval of nirogacestat has ushered in a new era of treatment for patients diagnosed with desmoid tumors. Several new molecules are expected to be approved over the coming years.

A Nationwide Prospective Clinical Trial on Active Surveillance in Patients With Non-intraabdominal Desmoid-type Fibromatosis: The GRAFITI Trial.

OBJECTIVE: To assess tumor behavior and the efficacy of active surveillance (AS) in patients with desmoid-type fibromatosis (DTF). SUMMARY OF BACKGROUND DATA: AS is recommended as initial management for DTF patients. Prospective data regarding the results of AS are lacking. METHODS: In this multicenter prospective cohort study (NTR4714), adult patients with non-intraabdominal DTF were followed during an initial AS approach for 3 years. Tumor behavior was evaluated according to Response Evaluation Criteria in Solid Tumors. Cumulative incidence of the start of an active treatment and progression-free survival (PFS) were calculated using the Kaplan-Meier method. Factors predictive for start of active treatment were assessed by Cox regression analyses. RESULTS: A total of 105 patients started with AS. Median tumor size at baseline was 4.1cm (interquartile range 3.0-6.6). Fifty-seven patients had a T41A CTNNB1 mutation; 14 patients a S45F CTNNB1 mutation. At 3 years, cumulative incidence of the start of active treatment was 30% (95% confidence interval [CI] 21-39) and PFS was 58% (95% CI 49-69). Median time to start active treatment and PFS were not reached at a median follow-up of 33.7 months. During AS, 32% of patients had stable disease, 28% regressed, and 40% demonstrated initial progression. Larger tumor size (≥5 cm; hazard ratio = 2.38 [95% CI 1.15-4.90]) and S45F mutation (hazard ratio = 6.24 [95% CI 1.92-20.30]) were associated with the start of active treatment. CONCLUSIONS: The majority DTF patients undergoing AS do not need an active treatment and experience stable or regressive disease, even after initial progression. Knowledge about the natural behavior of DTF will help to tailor the follow-up schedule to the individual patient.

Health-related Quality of Life of Patients With Non-Intra-abdominal Desmoid-Type Fibromatosis During Active Surveillance: Results of a Prospective Observational Study.

OBJECTIVE: To examine the impact of an active surveillance (AS) approach on the health-related quality of life (HRQoL) of patients with desmoid-type fibromatosis (DTF). BACKGROUND DATA: AS is recommended as initial approach in DTF patients. AS might however negatively affect HRQoL due to physical symptoms or stress and anxiety. METHODS: In a prospective observational study, the GRAFITI trial (NTR4714), DTF patients were followed during an initial AS approach for 3 years. HRQoL was assessed by the EORTC QLQ-C30 at baseline, 6, 12 and 24-month follow-up. Patients who completed questionnaires at≥1-time point were included in this analysis of the secondary endpoint. A multivariable linear mixed-effects model with random intercept was conducted to assess trends of HRQoL scores over time and to explore the effect of treatment strategy on HRQoL. RESULTS: All 105 patients enrolled in the GRAFITI trial were eligible for the HRQoL analyses. During 24-month follow-up, 75 patients (71%) continued AS and 30 patients (29%) started an active treatment (AT). DTF patients who continued AS demonstrated relatively stable HRQoL scores during follow-up. HRQoL scores of patients who started AT worsened compared to patients who continued AS, although no significant changes in HRQoL score over time were found in the mixed-model analyses. Overall, DTF patients who started AT scored significantly worse on pain (ß=10.08, P =0.039) compared to patients who continued AS. CONCLUSIONS: An initial AS approach did not impair HRQoL of DTF patients who continued AS over time, therefore providing further support for AS as the frontline approach in DTF patients. Longitudinal assessment of HRQoL should be part of clinical follow-up to identify patients who may need a change in treatment strategy.

Desmoid-type fibromatosis: imaging features and course.

Desmoid-type fibromatosis (DF) is a soft tissue tumor characterized by infiltrative growth and a tendency toward local recurrence, while it exhibits self-limiting behavior and shows spontaneous regression. With its unpredictable behavior, a change in treatment strategies from initial surgery to nonsurgical management has been proposed, and active surveillance is currently widely chosen as the initial treatment strategy for DF. We reviewed the imaging features of DF regarding its clinical course, focusing on regression cases, postoperative cases, and imaging changes after systemic treatment.

Evolving strategies for management of desmoid tumor.

Desmoid tumors (DTs) are rare soft tissue mesenchymal neoplasms that may be associated with impairments, disfigurement, morbidity, and (rarely) mortality. DT disease course can be unpredictable. Most DTs are sporadic, harboring somatic mutations in the gene that encodes for ß-catenin, whereas DTs occurring in patients with familial adenomatous polyposis have germline mutations in the APC gene, which encodes for a protein regulator of ß-catenin. Pathology review by an expert soft tissue pathologist is critical in making a diagnosis. Magnetic resonance imaging is preferred for most anatomic locations. Surgery, once the standard of care for initial treatment of DT, is associated with a significant risk of recurrence as well as avoidable morbidity because spontaneous regressions are known to occur without treatment. Consequently, active surveillance in conjunction with pain management is now recommended for most patients. Systemic medical treatment of DT has evolved beyond the use of hormone therapy, which is no longer routinely recommended. Current options for medical management include tyrosine kinase inhibitors as well as more conventional cytotoxic chemotherapy (e.g., anthracycline-based or methotrexate-based regimens). A newer class of agents, γ-secretase inhibitors, appears promising, including in patients who fail other therapies, but confirmation in Phase 3 trials is needed. In summary, DTs present challenges to physicians in diagnosis and prognosis, as well as in determining treatment initiation, type, duration, and sequence. Accordingly, evaluation by a multidisciplinary team with expertise in DT and patient-tailored management are essential. As management strategies continue to evolve, further studies will help clarify these issues and optimize outcomes for patients.

The Landmark Series: Desmoid.

Desmoid-type fibromatosis represents a challenge in the landscape of surgical oncology, for several reasons. The tumors can be infiltrative and locally aggressive, surgery may be morbid, and patients are usually young, and thus treatment sequelae must be managed for decades. Desmoids do not have metastatic potential, therefore management strategies for desmoids have evolved to employ frontline treatments that are largely non-operative. In fact, with unpredictable and benign behavior, we now recognize that desmoids can also stabilize and regress, making active observation an option for many patients. Moreover, many medical therapies are active in the disease. We reviewed landmark studies describing contemporary issues that affect treatment recommendations for desmoid patients: prognostic factors, indication to active surveillance, role of surgical margins, postoperative radiotherapy, and the most recent expert consensus papers.

Extra-abdominal desmoid tumor fibromatosis: a multicenter EMSOS study.

BACKGROUND: Extra-abdominal desmoid tumor fibromatosis (DTF) is a rare, locally aggressive soft tissue tumour. The best treatment modality for this patient cohort is still object of debate. QUESTIONS/PURPOSE: This paper aimed to (1) to compare the outcomes of DTF after different treatment modalities, (2) to assess prognostic factors for recurrence following surgical excision, and (3) to assess prognostic factors for progression during observation. METHODS: This was a retrospective multicenter study under the patronage of the European Musculoskeletal Oncology Society (EMSOS). All seven centres involved were tertiary referral centres for soft tissue tumours. Baseline demographic data was collected for all patients as well as data on the diagnosis, tumour characteristics, clinical features, treatment modalities and whether they had any predisposing factors for DTF. RESULTS: Three hundred eighty-eight patients (240 female, 140 male) with a mean age of 37.6 (±18.8 SD, range: 3-85) were included in the study. Two hundred fifty-seven patients (66%) underwent surgical excision of ADF, 70 patients (18%) were observed without therapy, the residual patients had different conservative treatments. There were no significant differences in terms of tumour recurrence or progression between the different treatment groups. After surgical excision, younger age, recurrent disease and larger tumour size were risk factors for recurrence, while tumours around the shoulder girdle and painful lesions were at risk of progression in the observational group. CONCLUSION: Local recurrence rate after surgery was similar to progression rates under observation. Hence, observation in DTF seems to be justified, considering surgery in case of dimensional progression in 2 consecutive controls (3 and 6 months) and in painful lesions, with particular attention to lesions around the shoulder girdle.

Desmoid Fibromatosis: Management in an Era of Increasing Options.

PURPOSE OF REVIEW: Desmoid fibromatosis (DF) is a locally aggressive clonal neoplasm with locally aggressive behavior and no metastatic potential. Historical treatment of DF has consisted primarily of up-front surgery when feasible. In recent years, recognition that DF can spontaneously stabilize or involute has allowed for many patients to be managed with watchful waiting rather than intervention. This review is intended to review recent developments in the treatment of DF. RECENT FINDINGS: Recent studies have demonstrated prospectively that patients with DF often have improvement in their lesions without intervention, enabling an initial period of surveillance as a standard option for patients with mild symptoms. Given the lengthening list of effective systemic treatments, including sorafenib, pazopanib, and experimental agents, there has been a less reliance on local therapies for those patients who require treatment. For patients with DF that require treatment, there is a growing list of options that includes radiation therapy (RT), percutaneous ablation, and a growing list of systemic agents with favorable toxicity profiles.

Desmoid fibromatosis: is the current picture changing?

Desmoid fibromatosis is a locally aggressive tumor with an unpredictable clinical course. Surgery was once the mainstay of treatment, but the treatment protocol has been constantly evolving and currently active surveillance is the front-line approach. There have been significant insights into the molecular biology with the addition of mutational analysis of CTNNB1 adding to prognostic information. We present a review of the literature with current practice guidelines, also including novel therapeutic targets and ongoing clinical trials, to unravel the next step in the management of sporadic desmoid fibromatosis.

Lay abstract Desmoid fibromatosis is an aggressive local tumor with continuously changing treatment paradigms. It requires MRI with biopsy for diagnosis and follow-up. Usually the tumor responds to a 'wait and watch' approach in most patients with either stable disease or regression on follow-up; a surgical plan is made only after multidisciplinary discussion, as surgery does not provide additional benefit in most patients. After a period of wait and watch, if there is disease progression, patients can be kept on medical management such as chemotherapy. Currently we have novel drugs for medical management like tyrosine kinase inhibitors, which result in disease stabilization in a majority of patients. In order to reduce the morbidity of treatment, it is essential for the patient to be on continuous follow-up and for clinicians to be updated with the continuously changing management of this disease.

Trends in diagnostic and therapeutic strategies for extra-abdominal desmoid-type fibromatosis: Japanese musculoskeletal oncology group questionnaire survey.

OBJECTIVE: The mainstay of treatment modality for extra-abdominal desmoid-type fibromatosis (DF) has shifted from surgery, which often impairs ADL/QOL, to conservative treatment including active surveillance. In the present study, we conducted a longitudinal survey on the diagnosis and treatment of DF at facilities belonging to the Japanese Musculoskeletal Oncology Group, which is a research group of facilities specializing in the treatment of bone and soft tissue tumors in Japan to clarify the transition of medical care for extra-abdominal DF. METHODS: The same questionnaire was administered in 2015 and 2018, and responses were obtained from 46 (69%) of 67 facilities and 42 (53%) of 80 facilities in 2015 and 2018, respectively. RESULTS: Although immunostaining for ß-catenin was often used for the pathological diagnosis in both 2015 and 2018, CTNNB1 mutation analysis was not performed either in 2015 or in 2018. As for the treatment strategy for resectable cases, surgical treatment including wide resection was selected at 11 facilities (24% of respondents) in 2015, and further decreased to 5 facilities (12%) in 2018. Conservative treatment with active surveillance or medical treatment was the most common treatment for both resectable and difficult-to-resect cases. COX-2 inhibitors and tranilast were often used in the drug treatment of both resectable and difficult-to-resect cases. Few facilities provided radiotherapy, methotrexate and vinblastine, or DOX-based chemotherapy for refractory cases in both 2015 and 2018. CONCLUSIONS: A good trend was found in the questionnaire survey. It will be further necessary to disseminate clinical practice guidelines to physicians more widely, and to have them understand and implement the most up-to-date medical practice strategies for this rare disease.

PROMIS Function Scores Are Lower in Patients Who Underwent More Aggressive Local Treatment for Desmoid Tumors.

BACKGROUND: Desmoid tumors of the extremities often present with pain and functional limitation, but treatment can lead to morbidity and recurrence is common. The impact of treatment with respect to traditional "oncologic" metrics (such as recurrence rate) has been studied extensively, with a shift in recent years away from local therapies as first-line management; however, little is known about the association between treatment modality and long-term functional outcomes for patients with this benign disease. QUESTIONS/PURPOSES: In a retrospective review of consecutive patients treated at two institutions, we asked: (1) Is event-free survival (EFS) different between patients who undergo local treatment and those who do not for primary as well as for recurrent desmoid tumors? (2) What treatment-related factors are associated with worse Patient-reported Outcomes Measurement Information System (PROMIS) function scores at a minimum of 1 year after treatment? METHODS: Between 1991 and 2017, 102 patients with desmoid tumors of the extremities (excluding those of the hands and feet) were treated at two institutions; of those, 85 patients with 90 tumors were followed clinically for at least 1 year (median [range] 59 months follow-up [12 to 293]) and were included in the present analysis. We attempted to contact all patients for administration of PROMIS function (Physical Function Short Form [SF] 10a and Upper Extremity SF v2.0 7a) and Pain Interference (SF 8a) questionnaires. Complete survey data (minimum 1 year follow-up) were available for 46% (39 of 102) of patients with 40 tumors at a median of 125 months follow-up; only these patients were included in PROMIS data analyses. Though there was no formal institutional treatment algorithm in place during the study period, surgical resection typically was the preferred modality for primary tumors; radiation therapy and systemic treatments (including cytotoxic or hormonal agents earlier in the study period, and tyrosine kinase inhibitors later) were often added for recurrent or very symptomatic disease. We coded treatment for each patient into discrete episodes, each defined by a particular treatment strategy: local treatment only (surgery and/or radiation), systemic treatment only, local plus systemic treatment, or observation; treatment episodes rendered at other institutions (that is, before referral) were not included in the analyses. Treatment failure was defined as recurrence after surgical resection, or clinically significant radiologic and/or symptomatic progression after systemic treatment, and EFS was defined as time from treatment initiation to treatment failure or final follow-up. Episodes of treatment for recurrent tumors were analyzed in a pooled fashion, wherein discrete treatment episodes for patients with multiple recurrences were included separately as independent events. We analyzed 56 primary tumors (54 patients), and 101 discrete treatment episodes for recurrent tumors (88 patients). Kaplan-Meier survival curves were constructed separately for the primary and recurrence cohorts, both comparing EFS among patients who received any local treatment (local treatment and local plus systemic treatment groups) versus those who did not (systemic treatment and observation groups). PROMIS function data were analyzed on the bases of patient- and treatment-specific variables, including the PROMIS Pain Interference score as a potential explanatory variable. RESULTS: Within both the primary and recurrence cohorts, there were no differences between the local treatment, systemic treatment, and local plus systemic treatment groups with respect to gender, age, axillary/hip girdle location, or tumor volume. Among primary tumors, 5-year EFS was 44% (95% CI 24 to 80) for the systemic-only group versus 15% (95% CI 5 to 44) for the local treatment group (p = 0.087). Within the pooled recurrence treatment episode cohort, 5-year EFS after systemic-only treatment was 70% (95% CI 52 to 94) versus 56% among patients receiving any local treatment (95% CI 44 to 70; p = 0.46). PROMIS function scores were lowest among patients who underwent two or more resections (39 versus 51 versus 47 for ≥2, 1, and 0 resections, respectively; p = 0.025); among those who received both surgery and radiation at any point, either concurrently or in separate treatment episodes, as compared with those who did not (39 versus 46; p = 0.047); and among those with higher levels of pain interference (38 versus 47 for pain interference scores > 50 versus < 50; p = 0.006). CONCLUSIONS: Patients treated with local modalities (surgery and/or radiation, with or without additional systemic therapy) did not experience improved EFS as compared with those treated without local modalities; this was the case for both the primary and the recurrent tumor cohorts. However, PROMIS function scores were lowest among patients who underwent two or more surgical interventions and among those treated with surgery and radiation at any time, suggesting that more aggressive local treatment may be associated with poorer long-term functional outcomes. Prospective collection of patient-reported outcomes data at multiple time points will allow for more direct correlations between treatment modality and impact on function and will help to elucidate the ideal management strategy for these benign but often-symptomatic tumors. LEVEL OF EVIDENCE: Level III, therapeutic study.

[A Case of Pelvic Desmoid-Type Fibromatosis Treated by Radiation and Medication Therapies].

The treatment for desmoid-type fibromatosis involves surgical resection and medication therapy, but the standard treatment has not yet been established. In the West, the usefulness of radiation therapy has been reported. We encountered a patient with desmoid-type fibromatosis in the pelvis who was treated by radiation and medication therapies and achieved a good tumor reduction effect. The patient was a 70-year-old man. He had a 6-year history of pain in the right leg and had a palpable mass on the right side of the anus; he was admitted to our department. CT showed a 12×7×12 cm mass in the pelvis, and CT-guided needle biopsy revealed a desmoid-type fibromatosis. Because tumor exclusion resulted in obstruction of the rectum, radiation therapy(60 Gy in 30 Fr)was started after performing transverse colon colostomy; simultaneous medication therapy with a COX-2 inhibitor and the anti-allergic agent tranilast was administered. Cystic degeneration was observed 5 months after the end of radiation therapy, and after 12 months, the tumor volume had halved. Around 28 months after the end of radiation therapy, medication treatment has been continued with slow contraction.

Desmoid tumors: diagnostic and therapeutic considerations.

A literature review on desmoid tumors was carried out, which are tumors that affect soft tissues with a locally aggressive behavior and are unable to metastasize. Sporadic cases are located on the extremities and chest wall; hereditary cases have an intra-abdominal predilection, and those associated with pregnancy occur on the abdominal wall. Imaging techniques assess disease extension. Trucut biopsy is the study of choice for diagnosis. Mutations in the CTNNB1 or APC genes cause an abnormal accumulation of b-catenin within the cell. In this review, an emphasis is made on therapeutic strategies' evolution and change, and current tools for decision making are analyzed, as well as clinical outcomes. Radiation therapy can play a therapeutic or adjuvant role. Advances in the understanding of the disease have allowed establishing better targeted treatments with lower morbidity; however, there are still unanswered questions regarding the choice of the ideal candidate for surveillance and/or early treatment. Data related to quality of life are also presented, as well as the uncertainty generated by this diagnosis for both doctor and patient.

Se realizó una revisión bibliográfica de los tumores desmoides, lo cuales afectan los tejidos blandos con un comportamiento localmente agresivo sin capacidad de producir metástasis. Los casos esporádicos se localizan en extremidades y pared torácica; los casos hereditarios tienen predilección intraabdominal y los asociados con el embarazo en la pared abdominal. Las técnicas de imagen evalúan la extensión de la enfermedad. La biopsia con aguja trucut es el estudio de elección para el diagnóstico. Las mutaciones en el gen CTNNB1 o en el gen de APC provocan acumulación anormal de betacatenina en la célula. En esta revisión se hace énfasis en la evolución y cambio de las estrategias terapéuticas y se analizan las actuales herramientas para la toma de decisiones, así como los resultados clínicos. La radioterapia puede tener un papel terapéutico o adyuvante. Los avances en la comprensión de la enfermedad han permitido establecer tratamientos mejor dirigidos y con menor morbilidad; sin embargo, aún existen interrogantes en cuanto a la elección del candidato ideal para la vigilancia o el tratamiento precoz. También se presentan datos relacionados con la calidad de vida y la incertidumbre que genera el diagnóstico en el médico y el paciente.

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.

Clinical features and treatment outcome of desmoid-type fibromatosis: based on a bone and soft tissue tumor registry in Japan.

BACKGROUND: Treatment modality of desmoid-type fibromatosis (DF) has changed from surgery with a wide surgical margin to conservative treatment. In this study, tumor characteristics of DF, transition of the treatment modality, and clinical outcome of surgical treatment were analyzed based on data obtained from the bone and soft tissue tumor registry established in Japan. METHODS: Data were collected as registration data and follow-up data. Five hundred and thirty registered cases of DF were identified, including 223 cases with follow-up data with or without surgical treatment. RESULTS: The number of registered patients increased gradually. The frequency of surgical treatment was gradually reduced year by year. The 3-year local recurrence free survival (LRFS) was 77.7%, with tumor location and size tending to correlate with LRFS. Interestingly, there was no significant difference in LRFS between wide and marginal margin (P = 0.34). CONCLUSIONS: The treatment modality has shifted from surgical to conservative treatment, with risk factors for surgical treatment similar to those noted in previous studies. The National registry system is crucial for a rare disease such as DF, and in the future, a population based registry system should be established to better comprehend the actual status of DF.

Sino-orbital desmoid tumor in a pediatric patient - Case report with review of literature.

We report a case of a 2-year-old female who presented with bilateral progressive proptosis, visual loss, nasal obstruction, and breathing difficulty. Magnetic resonance imaging revealed a large sino-orbital mass that was extending to the orbital apex and skull base. An initial diagnosis of rhabdomyosarcoma was made elsewhere on the basis of the presence of round and spindle cell tumor. Subsequent biopsy with immunohistochemical staining was positive for nuclear staining with ß-catenin, shifting the diagnosis to a myofibroblastic tumor, favoring desmoid-type fibromatosis. With image guidance, near complete excision of tumor was performed by a multidisciplinary team, while respecting danger zones such as the skull base and the optic nerve. Following a recurrence over 2 months, additional excision was performed with a 6-month treatment of methotrexate and vinblastine. Desmoid tumor is a rare form of soft tissue tumor uncommonly seen in the orbital area. Although benign, it is known to be recurrent and infiltrative. Few data are known and further information will aid in the management of these tumors.

Thermal diffusivity and perfusion constants from in vivo MR-guided focussed ultrasound treatments: a feasibility study.

PURPOSE: This study investigates the feasibility of non-invasively determining thermal diffusivity (α) and the Pennes perfusion parameter (w) from pre-clinical and clinical magnetic resonance-guided focussed ultrasound (MRgFUS) temperature data. MATERIALS AND METHODS: Pre-clinical MRgFUS experiments were performed in rabbit muscle (N = 3, 28 sonications) using three-dimensional MR thermometry. Eight sonications were made in a clinical QA phantom with two-dimensional thermometry. Retrospective property determination was performed on clinical uterine fibroid (N = 8, 9 sonications) and desmoid tumour (N = 4, 7 sonications) data. The property determination method fits an analytical solution to MRgFUS temperatures in the coronal MR plane, including all temperatures acquired during heating and one cooling image. When possible, additional cooling data were acquired for property determination. RESULTS: Rabbit α and w from Heating Data (α = 0.164 mm2s-1, w = 7.9 kg m-3 s-1) and Heating and Cooling Data (α = 0.146 mm2s-1, w = 3.3 kg m-3 s-1) were within the range of gold-standard invasive measurements, with >50% reduction in variability by including cooling data. QA phantom property determination with cooling data yielded properties within 3% of expected values (α = 0.144 mm2s-1, w = 0.0 kg m-3 s-1), a difference that was not statistically significant (p = 0.053). Uterine fibroid (Heating Data: α = 0.212 mm2s-1, w = 11.0 kg m-3 s-1) and desmoid tumour (Heating & Cooling Data: α = 0.245 mm2s-1, w = 4.7 kg m-3 s-1) properties are feasible but lack independent verification. CONCLUSIONS: Thermal diffusivity and the Pennes perfusion parameter can be obtained from in vivo data and with clinical MRgFUS protocols. Property values are consistently improved by including cooling data. The utility of this property determination method will increase as clinical protocols implement improved temperature imaging.