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.

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.

Multiparametric MR evaluation of uterine leiomyosarcoma and STUMP versus leiomyoma in symptomatic women planned for high frequency focussed ultrasound: accuracy of imaging parameters and interobserver agreement for identification of malignancy.

OBJECTIVE: To assess accuracy of and interobserver agreement on multiparametric MR findings to distinguish uterine leiomyoma (LM) from uterine leiomyosarcoma (LMS) and soft tissue tumour of unknown malignant potential. METHODS: Inclusion criteria: All females over 18 years with least one uterine mass measuring 5 cm or more in at least one of the three standard orthogonal dimensions on MR with histopathological confirmation of LM, LMS, or soft tissue tumour of unknown malignant potential (STUMP) in the 3 months following MR. Patients with LMS were drawn from a larger cohort being assessed for MR-guided focussed ultrasound (MRgFUS) suitability. Image evaluation: Assessed variables were: lesion margin, margin definition, T2 signal homogeneity, >50% of lesion with T2 signal brighter than myometrium, haemorrhage, restricted diffusion, contrast enhancement (CE), CE pattern, local lymphadenopathy and ascites. RESULTS: 32 LM, 10 LMS and 1 STUMP were evaluated. Ill-defined (p-value = 0.0003-0.0004) or irregular (p = 0.003-0.004) lesion margin, T2 hyperintensity >50% (p = 0.001-0.004), and peripheral CE (p = 0.02-0.05) were significantly more common in LMS/STUMP than LM for both radiologists. 10/11 (Reader 2) and 11/11 (Reader 1) LMS/STUMP displayed restricted diffusion but so did 63-80% of LM. Agreement was greatest for margin characteristics (κ = 0.73-0.81). CONCLUSION: Irregular/ill-defined lesion margin best distinguished LMS/STUMP from LM with good interrater reliability. ADVANCES IN KNOWLEDGE: Assessment of agreement regarding MR parameters distinguishing LM from LMS and STUMP has not previously been undertaken in a cohort including a large number of patients with LMS. This will help inform evaluation of females considering minimally invasive LM treatment.

Predictive value of magnetic resonance imaging in assessing myometrial invasion in endometrial cancer: is radiological staging sufficient for planning conservative treatment?

OBJECTIVES: There has been an increasing interest in accurately assessing tumors preoperatively to plan appropriate surgery or, in some low-risk patients, conservative treatment. We wish to determine the accuracy of magnetic resonance imaging (MRI) in predicting myometrial invasion in endometrial cancer and whether it is a safe and suitable tool for planning conservative treatment. MATERIALS AND METHODS: We compared MRI scans and final histopathologic diagnoses of 111 patients with endometrioid adenocarcinoma over a 6-year period at a major tertiary centre. Data were analyzed collectively and according to histological differentiation and types of MRI scans (1.5 vs 3 T). Outcomes were presence versus absence of myometrial invasion and recently revised International Federation of Gynecology and Obstetrics stage IA (up to 50% myometrial invasion) versus deep invasion. RESULTS: Magnetic resonance imaging had a high negative predictive value for the presence of deep invasion (87% overall and 95% for grade 1 disease). However, although the positive predictive value for the presence of any myometrial invasion was high, negative predictive values were poor (35% for all grades and 46% for grade 1). There was no difference between 1.5- and 3-T scanning. CONCLUSIONS: Magnetic resonance imaging is a suitable screening tool for the presence of stage IA disease under the newly revised International Federation of Gynecology and Obstetrics staging system. The significance of this finding will depend on whether clinicians are willing to treat all grade 1 stage IA disease (under the revised system) as low risk and to deem selected patients in this group suitable for more conservative treatment.

Isolated uterine metastasis from a lung adenocarcinoma.

A 65-year-old woman was referred with an incidental finding of a flurodeoxyglucose-avid uterine lesion, following excision of a local lung adenocarcinoma. MRI had features concerning for an atypical fibroid or smooth muscle tumour of uncertain malignant potential. She underwent a total abdominal hysterectomy and bilateral salpingo-oophorectomy. Histopathology demonstrated a leiomyoma infiltrated with adenocarcinoma consistent with a secondary lesion from the lung cancer. Among the small number of cases of uterine metastases of extra-pelvic primary cancers reported in the literature, those from lung cancers are very rare. Concerning features for an atypical fibroid included the patient's age and postmenopausal status, as well as positron emission tomography and MRI findings. A metastatic secondary cancer was not suspected. Diagnosis was only made after histopathological examination. This case represents a very unusual cause of a uterine mass. It demonstrates the importance of thorough preoperative work-up and accurate histopathological assessment.

Role of imaging in the routine management of endometrial cancer.

Endometrial cancer is the most common gynecologic cancer in women today. It is surgically staged, and while surgery is the primary treatment modality, the identification of disease extent-in particular extrauterine spread-prior to surgery is important to optimize treatment decision making. Ultrasound and MRI are useful for evaluating the extent of local disease, while CT and PET are used for detecting lymph node or distant metastases. Diffusion-weighted MRI has also been used for detecting small metastatic deposits in lymph nodes and omentum. Extrauterine soft tissue involvement can be detected by ultrasound, CT, MRI, and PET. Recently, intraoperative visualization techniques, such as sentinel lymph node mapping, are increasingly used to avoid extensive surgical staging without compromising treatment. Imaging is also used for planning adjuvant treatment and detection of postoperative residual disease in high-risk patients, monitoring and detecting recurrent disease, and in post-treatment surveillance of asymptomatic patients with high risk of relapse.

Clinical 24 month experience of the first MRgFUS unit for treatment of uterine fibroids in Australia.

AIM: To describe and evaluate treatment of uterine fibroids using Magnetic Resonance Guided Focused Ultrasound (MRgFUS) during its first 24 months of use at The Royal Women's Hospital Melbourne. METHODS: One hundred Victorian women were treated with MRgFUS using the ExAblate 2000 system. Treatment outcomes based on fibroid volume shrinkage measured at 4 and 12 months post-treatment and symptom severity score assessment (Symptom Severity Score Quality of Life - SSS-QOL) pre- and post- (4-6 weeks, 4, 6 and 12 months) treatment. RESULTS: Mean non-perfused volume of the treated fibroids were 67% ± 25% (n = 100) immediately post-treatment. At 4 months post-treatment, the treated fibroids demonstrated an average volume reduction of 29% ± 32% (n = 74) and at 12 months 38% ± 45% (n = 32). Mean symptom severity scores (SSS-QOL) improved by 51% from 59 ± 21 (n = 97) at baseline to 29 ± 17 (n = 36) by 12 months. CONCLUSION: From our experience, we believe there is a role for MRgFUS in the treatment of uterine fibroids in selected women.