Imaging for Early Detection of Pancreatic Ductal Adenocarcinoma: Updates and Challenges in the Implementation of Screening and Surveillance Programs.

Pancreatic ductal adenocarcinoma (PDA) is one of the most aggressive cancers. It has a poor 5-year survival rate of 12%, partly because most cases are diagnosed at advanced stages, precluding curative surgical resection. Early-stage PDA has significantly better prognoses due to increased potential for curative interventions, making early detection of PDA critically important to improved patient outcomes. We examine current and evolving early detection concepts, screening strategies, diagnostic yields among high-risk individuals, controversies, and limitations of standard-of-care imaging.

CT Esophagography for Evaluation of Esophageal Perforation.

Esophageal emergencies such as rupture or postoperative leak are uncommon but may be life threatening when they occur. Delay in their diagnosis and treatment may significantly increase morbidity and mortality. Causes of esophageal injury include iatrogenic (including esophagogastroduodenoscopy and stent placement), foreign body ingestion, blunt or penetrating trauma to the chest or abdomen, and forceful retching, also called Boerhaave syndrome. Although fluoroscopic esophagography remains the imaging study of choice according the American College of Radiology appropriateness criteria, CT esophagography has been shown to be at least equal to if not superior to fluoroscopic evaluation for esophageal injury. In addition, CT esophagography allows diagnosis of extraesophageal abnormalities, both as the cause of the patient's symptoms as well as incidental findings. CT esophagography also allows rapid diagnosis since the examination can be readily performed in most clinical settings and requires no direct radiologist supervision, requiring only properly trained technologists and a CT scanner. Multiple prior studies have shown the limited utility of fluoroscopic esophagography after a negative chest CT scan and the increase in accuracy after adding oral contrast agent to CT examinations, although there is considerable variability of CT esophagography protocols among institutions. Development of a CT esophagography program, utilizing a well-defined protocol with input from staff from the radiology, gastroenterology, emergency, and general surgery departments, can facilitate more rapid diagnosis and patient care, especially in overnight and emergency settings. The purpose of this article is to familiarize radiologists with CT esophagography techniques and imaging findings of emergent esophageal conditions. Online supplemental material is available for this article. ©RSNA, 2021.

Imaging for Oncologic Response Assessment in Lymphoma.

OBJECTIVE: The purpose of this article is to examine the role of different imaging biomarkers, focusing in particular on the use of updated CT and PET response criteria for the assessment of oncologic treatment effectiveness in patients with lymphoma but also discussing other potential functional imaging methods and their limitations. CONCLUSION: Lymph nodes are commonly involved by metastatic solid tumors as well as by lymphoma. Evolving changes in cancer therapy for lymphoma and metastases have led to improved clinical outcomes. Imaging is a recognized surrogate endpoint that uses established criteria based on changes in tumor bulk to monitor the effects of treatment. With the introduction of targeted therapies and novel antiangiogenic drugs, the oncologic expectations from imaging assessment are changing to move beyond simple morphologic methods. Molecular and functional imaging methods (e.g., PET, perfusion, DWI, and dual-energy CT) are therefore being investigated as imaging biomarkers of response and prognosis. The role of these advanced imaging biomarkers extends beyond measuring tumor burden and therefore might offer insight into early predictors of therapeutic response. Despite the potential benefits of these exciting imaging biomarkers, several challenges currently exist.

Exploration of Imaging Biomarkers for Predicting Survival of Patients With Advanced Non-Small Cell Lung Cancer Treated With Antiangiogenic Chemotherapy.

OBJECTIVE: The objective of this study was to compare imaging biomarkers, including (18)F-FDG PET, CT perfusion (CTP), and CT texture analysis (CTTA), in predicting the survival of patients with advanced non-small cell lung cancer (NSCLC) treated with antiangiogenic chemotherapy. SUBJECTS AND METHODS: A total of 35 patients (17 men and 18 women; median age, 64.0 years) with advanced NSCLC treated with antiangiogenic chemotherapy were evaluated. CTP and FDG PET were performed before the therapy, and blood flow, blood volume, mean transit time, and the maximum standardized uptake value (SUV max) of the tumor were measured. Texture parameters, including the mean value of pixels with positive values (MPP) and entropy (a measure of irregularity), were also measured on pretherapeutic unenhanced CT images, using CTTA software with a medium texture scale filtration. The best percent change in the tumor burden was also measured. These image-derived tumor parameters were then compared with progression-free survival (PFS) and overall survival (OS). RESULTS: In univariate Cox regression analysis, MPP and entropy were significantly correlated with PFS (p = 0.01 and p = 0.01, respectively), whereas SUV max, MPP, and entropy were significantly correlated with OS (p = 0.03, p = 0.04, and p = 0.0008, respectively). In Kaplan-Meier analysis, high MPP and low entropy were significantly associated with favorable PFS (p < 0.0001 and p = 0.03, respectively) and OS (p = 0.0009 and p = 0.005, respectively), and low SUV max was significantly associated with favorable OS (p = 0.01). CTP parameters and the best change in the tumor burden had no associations with survival. In multivariate analysis, only entropy was identified as an independent prognostic factor for OS (p = 0.02). CONCLUSION: CTTA is the optimal imaging biomarker for predicting the survival of patients with advanced NSCLC treated with antiangiogenic chemotherapy.

CT-guided implantation of intrahepatic fiducial markers for proton beam therapy of liver lesions: assessment of success rate and complications.

OBJECTIVE. The purpose of this study is to evaluate the safety and complications of CT-guided implantation of intrahepatic fiducial markers for proton beam therapy. MATERIALS AND METHODS. In this retrospective study, we reviewed 69 patients who underwent 149 percutaneous fiducial marker implantations for primary and metastatic hepatic tumors from April 2007 through July 2013. The implantations enabling satisfactory treatment planning and CT simulation were considered as technically successful. Major and minor procedure-related complications during and after fiducial marker implantation were documented. RESULTS. The success rate of fiducial marker implantation was 99.3% (148/149). In one patient, a fiducial marker migrated into the vascular system, which was realized during the procedure and required reimplantation. None of the patients was required to return for additional implantations. The major and minor complication rates were 0% and 2.9% (2/69), respectively. Both minor complications included small pneumothorax not requiring hospital admission. CONCLUSION. CT-guided placement of gold fiducial markers is associated with a high technical success rate with few complications, which is an essential step in the overall treatment planning and performance of proton beam therapy for the management of hepatic tumors.

New and evolving concepts in CT for abdominal vascular imaging.

Computed tomographic (CT) angiography has become the standard of care, supplanting invasive angiography for comprehensive initial evaluation of acute and chronic conditions affecting the vascular system in the abdomen and elsewhere. Over the past decade, the capabilities of CT have improved substantially; simultaneously, the expectations of the referring physician and vascular surgeons have also evolved. Increasingly, CT angiography is used as an imaging biomarker for treatment selection and assessment of effectiveness. However, the growing use of CT angiography has also introduced some challenges, as potential radiation-associated and contrast media-induced risks need to be addressed. These concerns can be partly confronted by modifying scanning parameters (applying a low tube voltage) with or without using software-based solutions. Most recently, multienergy technology has endowed CT with new capabilities offering improved CT angiographic image quality and novel plaque characterization while decreasing radiation and iodine dose. In this article, we discuss current and new approaches using both conventional and multienergy CT for studying vascular disease in the abdomen. We propose various approaches to overcoming commonly encountered image quality challenges in CT angiography. In addition, we describe supplemental strategies for improving patient safety that leverage the available technology.

Oncologic applications of dual-energy CT in the abdomen.

Dual-energy computed tomographic (DECT) technology offers enhanced capabilities that may benefit oncologic imaging in the abdomen. By using two different energies, dual-energy CT allows material decomposition on the basis of energy-dependent attenuation profiles of specific materials. Although image acquisition with dual-energy CT is similar to that with single-energy CT, comprehensive postprocessing is able to generate not only images that are similar to single-energy CT (SECT) images, but a variety of other images, such as virtual unenhanced (VUE), virtual monochromatic (VMC), and material-specific iodine images. An increase in the conspicuity of iodine on low-energy VMC images and material-specific iodine images may aid detection and characterization of tumors. Use of VMC images of a desired energy level (40-140 keV) improves lesion-to-background contrast and the quality of vascular imaging for preoperative planning. Material-specific iodine images enable differentiation of hypoattenuating tumors from hypo- or hyperattenuating cysts and facilitate detection of isoattenuating tumors, such as pancreatic masses and peritoneal disease, thereby defining tumor targets for imaging-guided therapy. Moreover, quantitative iodine mapping may serve as a surrogate biomarker for monitoring effects of the treatment. Dual-energy CT is an innovative imaging technique that enhances the capabilities of CT in evaluating oncology patients.

Initial experience with single-source dual-energy CT abdominal angiography and comparison with single-energy CT angiography: image quality, enhancement, diagnosis and radiation dose.

OBJECTIVES: To assess image quality of virtual monochromatic spectral (VMS) images, compared to single-energy (SE) CT, and to evaluate the feasibility of material density imaging in abdominal aortic disease. METHODS: In this retrospective study, single-source (ss) dual-energy (DE) CT of the aorto-iliac system in 35 patients (32 male, mean age 76.5 years) was compared to SE-CT. By post-processing the data from ssDECT, VMS images at different energies and material density water (WD) images were generated. The image quality parameters were rated on 5-point scales. The aorto-iliac attenuation and contrast-to-noise ratio (CNR) were recorded. Quality of WD images was compared to true unenhanced (TNE) images. Radiation dose was recorded and statistical analysis was performed. RESULTS: Image quality and noise were better at 70 keV (P < 0.01). Renal artery branch visualisation was better at 50 keV (P < 0.005). Attenuation and CNR were higher at 50 and 70 keV (P < 0.0001). The WD images had diagnostic quality but higher noise than TNE images (P < 0.0001). Radiation dose was lower using single-phase ssDECT compared to dual-phase SE-CT (P < 0.0001). CONCLUSION: 70-keV images from ssDECT provide higher contrast enhancement and improved image quality for aorto-iliac CT when compared to SE-CT at 120 kVp. WD images are an effective substitute for TNE images with a potential for dose reduction.

Determination of renal stone composition in phantom and patients using single-source dual-energy computed tomography.

PURPOSE: This study aimed to characterize the urinary tract stones in phantom and patients using single-source dual-energy computed tomography. MATERIALS AND METHODS: Twenty stones of pure crystalline composition (uric acid [UA], struvite, cystine, and calcium oxalate monohydrate) were assessed in a phantom and 11 patients (age 39-67 years) with urinary tract stones were evaluated. An initial low-dose unenhanced CT (tube potential, 120 kilovolts [peak]; milliampere range, 150-450; noise index, 26; section thickness, 5 mm) followed by a targeted dual-energy computed tomography acquisition on a single-source dual-energy computed tomography (Discovery CT 750 HDCT, GE) was performed. Uric acid and non-UA stones were defined using a 2-material decomposition (material density-iodine/water) algorithm. The stone effective atomic number (Zeff) was used to subclassify non-UA stones. The stone attenuation (Hounsfield unit) was also studied to determine its performance in predicting the composition. Ex vivo chemical analysis of the stone served as a criterion standard. RESULTS: Of the 59 verified stones (phantom, 20; patients, 39; mean size, 6 mm), there were 16 UA and 43 non-UA type. The material density images were 100% sensitive and accurate in detecting UA and non-UA stones. The Zeff accurately stratified struvite, cystine, and calcium (calcium oxalate monohydrate) stones in the phantom. In patients, Zeff identified 83% of calcium stones (n = 24), and in stones of mixed type, it resembled dominant composition. The Hounsfield unit measurements alone were 71% sensitive and 69% accurate in detecting the UA stones. CONCLUSIONS: Single-source dual-energy computed tomography can accurately predict UA and non-UA stone composition in vitro and in vivo. Substratification of non-UA stones of pure composition can be made in vitro and in vivo. In stones of mixed composition, the Zeff values reflect the dominant composition.

Radiation dose reduction at multidetector CT with adaptive statistical iterative reconstruction for evaluation of urolithiasis: how low can we go?

PURPOSE: To evaluate the performance of computed tomographic (CT) examinations at 80 and 100 kV with tube current-time products of 75-150 mA and the effect of adaptive statistical iterative reconstruction (ASIR) on CT image quality in patients with urinary stone disease. MATERIALS AND METHODS: In this HIPAA-compliant institutional review board-approved study, verbal consent for prospective low-dose CT and waivers of consent for retrospective review of CT scans were obtained. Between November 2010 and April 2011, 25 patients (15 men, 10 women; mean age, 35 years) with urolithiasis underwent 64-section multidetector CT with 75-150 mA and noise index of 30. Modified protocol was based on body weight (<200 lb [90 kg], 80 kV; >200 lb [90 kg], 100 kV). Images of 5-mm section thickness were reconstructed with filtered back projection (FBP) and 60% and 80% ASIR techniques, with 3-mm coronal and sagittal reformations. Two readers independently reviewed FBP and ASIR data sets for image quality (scale, 1-5), noise (scale , 1-3), and calculi (number, size, location). Confidence levels for urolithiaisis and alternate diagnoses were rated (scale, 1-3). In 13 patients, FBP CT images acquired with the reference standard departmental protocol were available for comparison. Radiation dose was compared between imaging series. Statistical analysis was performed with Wilcoxon signed rank and paired t tests. RESULTS: Modified-protocol FBP images showed low image quality (score, 2.5), with improvement on modified-protocol ASIR images (score, 3.4) (P=.03). All 33 stones (mean diameter, 6.1 mm; range, 2-28 mm) at modified-protocol CT were diagnosed by both readers. In 20 of 25 patients (80%), ASIR images were rated adequate for rendering other diagnoses in the abdomen (score, 2.0), as opposed to FBP images (score, 1.3). Mean radiation dose for modified-protocol CT was 1.8 mGy (1.3 mGy for patients<200 lb; 2.3 mGy for patients>200 lb) in comparison with 9.9 mGy for reference-protocol CT (P=.001). CONCLUSION: Image quality improvements with ASIR at reduced radiation dose of 1.8 mGy enabled effective evaluation of urinary calculi without substantially affecting diagnostic confidence. © RSNA, 2012.

Indirect computed tomography venography of the lower extremities using single-source dual-energy computed tomography: advantage of low-kiloelectron volt monochromatic images.

PURPOSE: To study the performance of dual-energy indirect computed tomography (CT) venography from single-source dual-energy CT in the assessment of lower extremity deep venous thrombosis (DVT). MATERIALS AND METHODS: In a retrospective study, 110 patients suspected to have pulmonary embolism (PE) underwent dual-energy CT venography on a single-source dual-energy CT scanner as a part of CT pulmonary angiography protocol at 3 minutes after injection of contrast material. Two radiologists evaluated 50-kiloelectron volt (keV) and 70-keV monochromatic images reconstructed from a dual-energy CT scan for image quality, image noise, venous contrast, and confidence level in interpretation for DVT using a scale of 1-5. In addition, a combined 50-keV and 70-keV data set was assessed for confidence level in image interpretation. Attenuation, contrast-to-noise ratio (CNR), and objective noise were measured in bilateral common femoral and popliteal veins. Data were analyzed using Student t test and Wilcoxon rank sum test. Radiation dose was measured for dual-energy CT venography protocol. RESULTS: A diagnosis of DVT was made in 8 of 110 patients (7.27%). The subjective image quality was comparable between 50-keV and 70-keV images (4.3 vs 4.5; P > .05). The subjective venous contrast opacification (4.7 vs 3.5; P = .0036) and confidence (4.8 vs 3.9; P = .0028) in image interpretation were superior at 50 keV. Confidence level for interpretation on combined 50-keV and 70-keV series (score 4.7) was similar to that for 50-keV series (score 4.8). Compared with 70-keV data, 50-keV data yielded 90% increase in intravascular CT attenuation (207.4 Hounsfield units [HU] ± 39.0 vs 106.8 HU ± 7.6; P <.0001) and higher CNR (10.7 ± 4.07 vs 7.2 ± 4.1; P = .0001) of the deep veins. However, objective noise at 50 keV was higher (14.8 HU vs 6.5 HU; P = .0031). Because of inadequate contrast opacification, 6% of CT venography studies were deemed suboptimal for rendering a diagnostic interpretation on 70-keV images, but these images were considered acceptable at 50 keV. The mean effective radiation dose for the dual-energy CT venography examination was 4.2 mSv. CONCLUSIONS: Optimal image quality with substantially higher venous attenuation is provided by 50-keV monochromatic images from dual-energy CT venography acquisition compared with 70-keV images. The 50-keV monochromatic images increase the confidence in the image interpretation of DVT and decrease the number of indeterminate studies.

Qualitative assessment of enhancement in a renal mass: contribution of subtraction CT.

PURPOSE: To evaluate the impact of subtraction CT on reader confidence and diagnostic accuracy when characterizing renal masses. MATERIALS AND METHODS: In this institutional review board-approved retrospective study, 159 patients (85 men and 74 women; mean age, 62.6 years; range, 22-88 years) underwent routine unenhanced and contrast-enhanced multidetector computed tomography (MDCT) for renal lesion characterization. Subtraction images were subsequently generated on scanner console. Two readers independently reviewed the MDCT images to characterize presence of enhancement using a 6-point scale during 3 blinded review sessions of (1) only subtraction, (2) routine, and (3) combined subtraction and routine images. The standard of reference consisted of either histopathology or follow-up imaging and clinical data. RESULTS: Of the 240 lesions evaluated, 60 lesions (mean, 3.2 cm; range, 1-7.5 cm) were enhancing and 180 lesions (mean, 2.7 cm; range, 0.5-12 cm) were nonenhancing. For determination of lesion enhancement, a combined evaluation of routine MDCT and subtraction images improved reader confidence in 60% to 63% of lesions (P < 0.001). The combined evaluation also provided the highest sensitivity (97%), specificity (99%), and accuracy (98.9%). CONCLUSION: When used in combination with routine image interpretation, subtraction CT improves reader confidence and diagnostic accuracy in identifying enhancement in renal lesions.

Low-dose MDCT and CT enterography of patients with Crohn disease: feasibility of adaptive statistical iterative reconstruction.

OBJECTIVE: The purpose of this study was to evaluate the image quality and diagnostic performance of low-dose MDCT and CT enterography with adaptive statistical iterative reconstruction (ASIR) in the evaluation of Crohn disease. SUBJECTS AND METHODS: Forty-eight patients (20 men, 28 women; mean age, 33.3 years; range, 17-83 years) with known or suspected Crohn disease who underwent low-dose MDCT and CT enterography with ASIR between December 2008 and December 2009 were included in the study. Twenty-seven patients had previously undergone standard-dose 64-MDCT and CT enterography with filtered back projection (FBP), and those images were used for comparison. The weight-based i.v. contrast protocol and scan parameters (120 kVp, 5-mm section thickness, 0.5-second rotation, pitch of 1.375, 64 × 0.625 mm detector configuration) were constant for the two techniques except for a higher noise index (×1.3) in the ASIR group. Two blinded readers reviewed 75 randomized MDCT-CT enterographic scans of 48 patients to assess image quality and diagnostic performance in the evaluation of Crohn disease, and the radiation dose for the studies was estimated. RESULTS: All 75 MDCT and CT enterographic scans had acceptable quality for diagnostic interpretation. Findings of Crohn disease were seen on 63 of 75 scans (84%). Low-dose scans in the ASIR group had optimal image quality and were rated comparable to or better than standard-dose FBP images (mean score, 4.2 vs 3.87; p = 0.007). The subjective image noise score (mean, 1.43 vs 1.58; p = 0.2) and objective image noise measurements were lower for ASIR images (p < 0.001). Low-dose studies with ASIR allowed average dose reduction of 34.5% compared with standard-dose scans with FBP (volume CT dose index for ASIR, 7.7 ± 2.1 mGy; for FBP, 12 ± 5.5 mGy; p < 0.01). CONCLUSION: Low-dose MDCT and CT enterographic studies reconstructed with ASIR were of appropriate quality for confident evaluation of the manifestations of Crohn disease while allowing approximately 34% dose reduction in comparison with FBP technique.

Computed Tomography Techniques, Protocols, Advancements, and Future Directions in Liver Diseases.

Computed tomography (CT) is often performed as the initial imaging study for the workup of patients with known or suspected liver disease. Our article reviews liver CT techniques and protocols in clinical practice along with updates on relevant CT advances, including wide-detector CT, radiation dose optimization, and multienergy scanning, that have already shown clinical impact. Particular emphasis is placed on optimizing the late arterial phase of enhancement, which is critical to evaluation of hepatocellular carcinoma. We also discuss emerging techniques that may soon influence clinical care.

Structured Reporting in Ultrasound.

Structured reporting of ultrasound examinations can add value throughout the imaging chain. Reports may be created in a more efficient manner, with increased accuracy and clarity. Communication with referring providers and patients may be improved. Patient care can be enhanced through improved adherence with guidelines and local best practices. Radiology departments may benefit from improved billing and quality reporting. Consistent discrete data can enable research and collaborations between institutions. This article will review the multifaceted impact of structuring ultrasound reports.

White paper on pancreatic ductal adenocarcinoma from society of abdominal radiology's disease-focused panel for pancreatic ductal adenocarcinoma: Part I, AJCC staging system, NCCN guidelines, and borderline resectable disease.

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive gastrointestinal malignancy with a poor 5-year survival rate. Accurate staging of PDAC is an important initial step in the development of a stage-specific treatment plan. Different staging systems/consensus statements convened by different societies and academic practices are currently used. The most recent version of the American Joint Committee on Cancer (AJCC) tumor/node/metastases (TNM) staging system for PDAC has shifted its focus from guiding management to assessing prognosis. In order to preoperatively define the resectability of PDAC and to guide management, additional classification systems have been developed. The National Comprehensive Cancer Network (NCCN) guidelines, one of the most commonly used systems, provide recommendations on the management and the determination of resectability for PDAC. The NCCN divides PDAC into three categories of resectability based on tumor-vessel relationship: 'resectable,' 'borderline resectable,' and 'unresectable'. Among these, the borderline disease category is of special interest given its evolution over time and the resulting variations in the definition and the associated recommendations for management between different societies. It is important to be familiar with the evolving criteria, and treatment and follow-up recommendations for PDAC. In this article, the most current AJCC staging (8th edition), NCCN guidelines (version 2.2019-April 9, 2019), and challenges and controversies in borderline resectable PDAC are reviewed.

White paper on pancreatic ductal adenocarcinoma from society of abdominal radiology's disease-focused panel for pancreatic ductal adenocarcinoma: Part II, update on imaging techniques and screening of pancreatic cancer in high-risk individuals.

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive gastrointestinal malignancy with a poor 5-year survival rate. Its high mortality rate is attributed to its aggressive biology and frequently late presentation. While surgical resection remains the only potentially curative treatment, only 10-20% of patients will present with surgically resectable disease. Over the past several years, development of vascular bypass graft techniques and introduction of neoadjuvant treatment regimens have increased the number of patients who can undergo resection with a curative intent. While the role of conventional imaging in the detection, characterization, and staging of patients with PDAC is well established, its role in monitoring treatment response, particularly following neoadjuvant therapy remains challenging because of the complex anatomic and histological nature of PDAC. Novel morphologic and functional imaging techniques (such as DECT, DW-MRI, and PET/MRI) are being investigated to improve the diagnostic accuracy and the ability to measure response to therapy. There is also a growing interest to detect PDAC and its precursor lesions at an early stage in asymptomatic patients to increase the likelihood of achieving cure. This has led to the development of pancreatic cancer screening programs. This article will review recent updates in imaging techniques and the current status of screening and surveillance of individuals at a high risk of developing PDAC.

Sonographic Appearances of Portal Vein Abnormalities.

Portal venous system evaluation is required in many clinical circumstances, as substantial morbidity and mortality can be associated with a spectrum of portal vein abnormalities. Portal venous system pathologies can be congenital or acquired, and the knowledge of their imaging appearances will allow for a confident diagnosis and appropriate treatment options. In addition, a firm understanding of anatomical variants is important for planning surgical procedures and percutaneous interventions of the liver. This article will review various imaging appearances of portal venous systems abnormalities.

Magnetic Resonance-Guided Focused Ultrasound: A Brief Review With Emphasis on the Treatment of Extra-abdominal Desmoid Tumors.

Magnetic resonance-guided focused ultrasound (MRgFUS) utilizes high-intensity focused ultrasound to noninvasively, thermally ablate lesions within the body while sparing the intervening tissues. Magnetic resonance imaging provides treatment planning and guidance, and real-time magnetic resonance thermometry provides continuous monitoring during therapy. Magnetic resonance-guided focused ultrasound is ideally suited for the treatment of extra-abdominal desmoid fibromatosis due to its noninvasiveness, lack of ionizing radiation, low morbidity, and good safety profile. Conventional treatments for these benign tumors, including surgery, radiation, and chemotherapy, can carry significant morbidity. Magnetic resonance-guided focused ultrasound provides a safe and effective alternative treatment in this often-young and otherwise healthy patient population. While there is considerable experience with MRgFUS for treatment of uterine fibroids, painful bone lesions, and essential tremor, there are few reports in the literature of its use for treatment of benign or malignant soft tissue tumors. This article reviews the principles and biologic effects of high-intensity focused ultrasound, provides an overview of the MRgFUS treatment system and use of magnetic resonance thermometry, discusses the use of MRgFUS for the treatment of extra-abdominal desmoid tumors, and provides several case examples.