Musculoskeletal Soft Tissue Masses Research Articles

Multiparametric Evaluation of Soft Tissue Sarcoma: Current Perspectives and Future Directions

Imaging plays an essential role in diagnosing and managing musculoskeletal soft tissue masses. It provides anatomic details and aids in the characterization and prognostication of tumors. Advanced imaging is also essential for assessing treatment response and post-treatment surveillance. Several novel imaging techniques are now available that provide additional functional and metabolic information about these tumors. This additional information may be used to predict the biological behavior of the tumors and effectively assess the treatment response for optimizing their management. This article focuses on multiparametric imaging evaluation of soft tissue masses with a discussion of advancements in the domains of ultrasound, MRI, and CT imaging and how these may be helpful in pre- and post-treatment assessment of soft tissue tumors. Current perspectives on the role of diffusion imaging, perfusion imaging, and MR spectroscopy have been highlighted, and future directions of metabolic imaging are briefly outlined. As these advances hold a promising role in the multidisciplinary management of soft tissue sarcomas, it is important for the radiologist to be familiar with the latest advances and developments in imaging soft tissue tumors.

Role of diffusion-weighted MRI in evaluation of pediatric musculoskeletal soft tissue masses

BackgroundIn pediatric patients, soft tissue masses encompass a wide heterogeneous group of benign and malignant lesions. MRI is a powerful diagnostic tool in the workup of soft tissue tumors in children, and it helps in characterization of lesion and evaluation of the extent of the lesion. However, conventional MRI techniques are not specific in differentiating benign from malignant lesions. So to improve characterization of tumors, DWI was added to MRI techniques as it increases sensitivity and specificity by detecting the micro-diffusion changes of water into intra- and extracellular spaces. The aim of this work was to highlight the diagnostic value of DWI in detection and characterization of different musculoskeletal soft tissue masses in pediatrics.ResultsThere was a statistically significant difference regarding the mean ADC value of benign and malignant masses (P value = 0.001*). The mean ADC value for all benign masses (n = 41) was 1.495 ± 0.55 SD × 10–3 mm2/s, while the mean ADC value for all malignant masses (n = 21) was 0.449 ± 0.27 SD × 10–3 mm2/s. The cutoff ADC value between benign and malignant masses was 0.88 × 10–3 mm2/s. This cutoff ADC value has sensitivity of 100.0%, specificity of 92.3%, PPV of 66.7%, NPV of 100.0% and diagnostic accuracy of 93.3%.ConclusionIn pediatric patients, DWI is an innovative valuable noninvasive imaging technique for characterization of musculoskeletal soft tissue masses and discrimination between benign and malignant masses.

Role of Diffusion Weighted MRI in Characterization of Musculoskeletal Soft Tissue Tumors

Abstract Background: Magnetic Resonance Imaging is the method of choice for the diagnostic work-up of soft tissue tumors. It is the modality of choice to evaluate such masses, because of its excellent soft tissue contrast. Aim of Study: To assess the efficacy of Diffusion weighted MRI in characterization of musculoskeletal soft tissue tumors. Patients and Methods: The current study enrolled 20 patients (11 female and 9 male) with musculoskeletal STTs with mean age was 41.08±11.54 year. The most frequent affected site with the swelling was the thigh (48%) followed by the arm (20%). Four (16%) patients suffered from leg swelling while three (12%) patients had shoulder swelling. Our results revealed that malignant musculoskeletal soft tissue masses had significantly lower ADC value in comparison to those with benign masses (0.70±0.09 vs. 1.58±0.52x10-3m2/s; p < 0.001). Results: Patients with malignant lesions had significantly lower ADC value in comparison to those with benign lesions (0.70±0.09 vs. 1.58±0.52 (103mm2/s). Myxoma had the highest ADC value that was 2.44 (103mm2/s) while sarcoma had lowest value that was 0.54±0.03 (103mm2/s). It was noticed that MRI had 100% sensitivity and 81.8% specificity for diagnosis of malignant musculoskeletal soft tissue masses with overall accuracy was 92% and area under curve was 0.91 at cut off value was <1.14 (103mm2/s). Based on final diag-nosis; MRI was successful in diagnosis of all cases with malignant musculoskeletal soft tissue masses but as the same time, MRI falsely diagnosed two cases with benign nature to be malignant. Those two cases were finally diagnosed to be lipoma. Conclusion: Based on the current study, DWI-MRI con-sidered the method of choice for the characterization of muscul oskel etal STTs; however, DW-MRI with ADC mapping is a rapidly, valuable, non-invasive, non-contrast tool for reliably differentiating between benign and malignant STTs. It's recommended to perform such study in large sample of patients and in more centers to confirm the great values of DWI-MRI in evaluation of such lesions.

Simple Stepwise Approach to Differentiate Cyst-Like Soft-Tissue Masses by Using Time-Resolved Magnetic Resonance Angiography

This retrospective study aimed to differentiate cyst-like musculoskeletal soft-tissue masses by using time-resolved magnetic resonance angiography (MRA). During May 2015 to November 2019, patients with cyst-like soft-tissue masses examined through contrast-enhanced MRI followed by histologic diagnosis were included. The masses were classified into vascular lesions, solid lesions, and true cysts. Size, T1 hyperintensity, T2 composition, perilesional edema, time-resolved MRA, and static internal enhancement were assessed. The time-resolved MRA manifestations were classified into vascular pooling, solid stain, and occult lesion. Imaging predictors for each type of mass were identified through logistic regression and were used to develop a diagnostic flowchart. A total of 80 patients (47 men; median age, 42 years) were included, with 22 vascular lesions, 38 solid lesions, and 20 true cysts. The T2 composition, time-resolved MRA, and static internal enhancement were significantly different among the masses. Vascular pooling on time-resolved MRA was the sole predictor of vascular lesions (odds ratio = 722.0, p < 0.001). Solid stain on time-resolved MRA was the sole predictor of solid lesions (odds ratio = 73.6, p < 0.001). Occult lesion on time-resolved MRA (odds ratio = 7.4, p = 0.001) and absence of static internal enhancement (odds ratio = 80.0, p < 0.001) both predicted true cysts, while the latter was the sole predictor of true cysts after multivariate analysis. A diagnostic flowchart based on time-resolved MRA correctly classified 89% of the masses. In conclusion, time-resolved MRA accurately differentiates cyst-like soft-tissue masses and provides guidance for management.

A review of paediatric soft tissues masses referred to a tertiary musculoskeletal sarcoma centre.

To determine the differential diagnosis of musculoskeletal soft tissue masses in children referred to a specialist musculoskeletal oncology unit. All children (0-18 y) referred to a specialist musculoskeletal oncology unit over a 20-month period (September 2018-May 2020) were retrospectively reviewed. Demographic data and referral diagnoses were obtained from the electronic patient notes. MRI findings and histopathological results were recorded. The comparison of non-neoplastic, benign neoplastic and malignant diagnoses at the point of referral and final diagnosis was determined. 116 patients were included, 60 (51.7%) males and 56 (48.3%) females with mean age of 10.6 years (3 months-18 years). 69 (59.5%) patients were referred with a suspected sarcoma, 29 (25.0%) with a suspected benign tumour and 18 (15.5%) with a non-neoplastic lesion. A diagnosis was achieved by histological assessment in 61 (52.6%) cases, microbiological assessment in 3 (2.6%) or clinical and imaging assessment in 52 (44.8%). 67 (57.8%) cases had non-neoplastic pathology, 39 (33.6%) a benign tumour, 4 (3.4%) an intermediate-grade tumour, 6 (5.2%) a malignant tumour. Although over half of children referred to a specialist musculoskeletal oncology unit were suspected of having a soft tissue sarcoma at referral, only 5.2% were diagnosed with a malignant tumour. Approximately, 6 of 69 (8.7%) children referred to a specialist musculoskeletal oncology unit with a suspected soft tissue sarcoma will have a malignant lesion. Most paediatric soft tissue masses are non-neoplastic, the commonest diagnosis being a vascular malformation.

The safety of primary surgical excision of small deep indeterminate musculoskeletal soft tissue masses.

To determine the suitability of primary excision of small indeterminate deep soft tissue masses presenting to a tertiary musculoskeletal oncology service. Review of all patients referred to a specialist musculoskeletal oncology service over a 20-month period with a deep indeterminate soft tissue mass by non-contrast MRI criteria that was recommended for primary surgical excision due to relatively small size (<30 mm). Data collected included age, gender, site and maximal size of the lesion, and final histological diagnosis for excised lesions. 85 patients were included, mean lesion size being 12 mm (range 5-29 mm). Primary surgical resection had been undertaken in 69 cases (81.2%) by the conclusion of data collection, 36 males and 33 females with mean age of 45.6 years (range 11-80 years). Of these, 11 cases (15.9%) were non-neoplastic, 53 (76.8%) were benign, 1 (1.4%) was intermediate grade, while 4 (5.8%) were malignant including 3 synovial sarcomas. Two of these were treated with re-excision of the tumour bed showing no residual disease, with no evidence of local recurrence at a mean of 10.7 months post-excision. Primary surgical excision of small deep soft tissue masses that are indeterminate by non-contrast MRI criteria is considered a safe procedure when undertaken in a specialist musculoskeletal oncology service, with only 4 of 69 cases (5.8%) being malignant. Small indeterminate deep soft tissue masses can safely be treated with primary excision in the setting of a specialist musculoskeletal oncology service.

Ultrasound Elastography in Musculoskeletal Radiology: Past, Present, and Future.

Ultrasound elastography (USE) is becoming an important adjunct tool in the evaluation of various musculoskeletal (MSK) traumatic conditions and diseases, with an increasing number of applications and publications in recent years. This rapidly evolving technique enhances the conventional ultrasound (US) examination by providing information on the elastic properties of tissue alongside the morphological and vascular information obtained from B-mode US and Doppler imaging. Those performing USE must have basic knowledge of its proper imaging techniques and limitations. In this review article, we place the USE in historical perspective and discuss basic techniques and current applications of USE in the evaluation of various traumatic and pathologic conditions of fasciae, nerves, muscles, tendons, ligaments, and MSK soft tissue masses.

Inter- and intra-reader reproducibility of shear wave elastography measurements for musculoskeletal soft tissue masses

ObjectiveTo determine inter- and intra-reader reproducibility of shear wave elastography measurements for musculoskeletal soft tissue masses.Materials and methodsIn all, 64 patients with musculoskeletal soft tissue masses were scanned by two readers prior to biopsy; each taking five measurements of shear wave velocity (m/s) and stiffness (kPa). A single lesion per patient was scanned in transverse and cranio-caudal planes. Depth measurements (cm) and volume (cm3) were recorded for each lesion, for each reader. Linear mixed modelling was performed to assess limits of agreement (LOA), inter- and intra-reader repeatability, including analyses for measured depth and volume.ResultsOf the 64 lesions scanned, 24 (38%) were malignant. Bland-Altman plots demonstrated negligible bias with wide LOA for all measurements. Transverse velocity was the most reliable measure—intraclass correlation (95% CI) = 0.917 (0.886, 1)—though reader 1 measures could be between 38% lower and 57% higher than reader 2 [ratio-scale bias (95% LOA) = 0.99 (0.64, 1.55)]. Repeatability coefficients indicated most disagreement resulted from poor within-reader reproducibility. LOA between readers calculated from means of five repeated measurements were narrower—transverse velocity ratio-scale bias (95% LOA) = 1.00 (0.74, 1.35). Depth affected both estimated velocity and repeatability; volume also affected repeatability.ConclusionThis study found poor repeatability of measurements with wide LOA due mostly to intra-reader variability. Transverse velocity was the most reliable measure; variability may be affected by lesion depth. At least five measurements should be reported with LOA to assist future comparability between shear wave elastography systems in evaluating soft tissue masses.

Magnetic resonance imaging biomarkers in musculoskeletal soft tissue tumors: Review of conventional features and focus on nonmorphologic imaging.

The majority of peripheral musculoskeletal soft tissue masses encountered in routine clinical practice are benign and associated with an excellent prognosis, whereas a small proportion of soft tissue masses are malignant and are associated with higher morbidity and mortality. Owing to the excellent tissue contrast resolution provided, magnetic resonance imaging (MRI) is a primary modality for the diagnostic evaluation of soft tissue masses, particularly for defining the anatomic extent. MRI is also useful for the characterization of soft tissue masses; however, after the exclusion of cysts and lipomas, it is challenging to accurately categorize neoplastic lesions as benign or malignant with conventional anatomic MRI. Quantitative MRI biomarkers obtained with nonconventional pulse sequences are becoming increasingly available, and can improve the accuracy of determining the character of soft tissue masses. In this article we discuss established qualitative and emerging quantitative MRI-based biomarkers available with dynamic contrast-enhanced MRI, diffusion-weighted imaging, and MR spectroscopy and their utility for the characterization of untreated soft tissue masses. Level of Evidence: 5 Technical Efficacy Stage: 5 J. Magn. Reson. Imaging 2019;50:11-27.

Diffusion weighted MRI of soft tissue masses: Can measurement of ADC value help in the differentiation between benign and malignant lesions?

ObjectiveTo assess the ability of DWI & numerical ADC values associated with routine MRI in classification of different musculoskeletal soft tissue masses. Patient & method45 patients (32 females and 13 males) with known or clinically suspected to have musculoskeletal soft tissue masses were included. Their age ranging from (9–72) years, they all subjected to conventional MRI, DWI and ADC values were calculated, The diagnosis was confirmed by histologic biopsy. ResultsBenign neoplasms (except for lipomas) showed values of ADC above 1.275 × 10−3 mm2/s while malignant soft tissue tumors (except for high-grade myxofibrosarcoma) have ADC values below 1.1 × 10−3 mm2/s. Mean ADC values for benign and malignant soft tissue tumors were 1.53 ± 0.91 mm2/s and 0.84 ± 0.33 mm2/s respectively with cutoff value 1.235 mm2/s showing sensitivity, specificity & accuracy 73%, 91.7% & 80.3% respectively. Tru cut biopsy done in (28) patients (8 benign & 20 malignant masses), frozen sections confirmed diagnosis of other 10 benign masses and reconfirmed diagnosis of the previously biopsied 20 malignant masses, the last 7 patients couldn't be biopsied & were diagnosed from patient medical profile at our institute. ConclusionAddition of DWI &quantitative ADC mapping to routine MR examination is advised for evaluation of soft tissue tumors especially in the inconclusive cases.

Ultrasound in the Evaluation of Musculoskeletal Soft-Tissue Masses

Ultrasound in the Evaluation of Musculoskeletal Soft-Tissue Masses

Imaging of Soft-Tissue Musculoskeletal Masses: Fundamental Concepts.

Radiologic evaluation of musculoskeletal soft-tissue masses has changed dramatically with the continued improvements in imaging technology. The integration of advanced imaging has provided the radiologist with a wide range of assessment tools, but as with all powerful arsenals, selection and application of the appropriate imaging method can be problematic. Although the choices available for imaging evaluation of musculoskeletal masses have changed dramatically, the basic objectives of this assessment have remained constant: diagnosis and staging. The basic principles for evaluating musculoskeletal soft-tissue masses and achieving these objectives have not changed. This article addresses application of the current imaging methods to assessment of soft-tissue musculoskeletal masses, emphasizing fundamental concepts. We do not intend to provide a comprehensive review of imaging techniques, but rather to provide a useful review of the concepts needed to select the appropriate initial imaging method, magnetic resonance (MR) imaging field of view, MR imaging sequences, contrast material requirements, and rapid image acquisition techniques. We also address use of the new quantitative techniques of chemical shift and diffusion-weighted imaging. Finally, we review the current uses of computed tomography and ultrasonography. Although the choices available for imaging evaluation of musculoskeletal masses have changed dramatically within the past decade, appropriate application of the fundamental concepts of imaging will maximize the diagnostic utility of imaging examinations. ©RSNA, 2016.

Do quantitative and qualitative shear wave elastography have a role in evaluating musculoskeletal soft tissue masses?

ObjectivesTo determine if quantitative and qualitative shear wave elastography have roles in evaluating musculoskeletal masses.Methods105 consecutive patients, prospectively referred for biopsy within a specialist sarcoma centre, underwent B-mode, quantitative (m/s) and qualitative (colour map) shear wave elastography. Reference was histology from subsequent biopsy or excision where possible. Statistical modelling was performed to test elastography data and/or B-mode imaging in predicting malignancy.ResultsOf 105 masses, 39 were malignant and 6 had no histology but benign characteristics at 12 months. Radiologist agreement for B-mode and elastography was moderate to excellent Kw 0.52-0.64; PABAKw 0.85-0.90). B-Mode imaging had 78.8% specificity, 76.9% sensitivity for malignancy. Quantitatively, adjusting for age, B-mode and lesion volume there was no statistically significant association between longitudinal velocity and malignancy (OR [95% CI] 0.40[0.10, 1.60], p=0.193), but some evidence that higher transverse velocity was associated with decreased odds of malignancy (0.28[0.06, 1.28], p=0.101). Qualitatively malignant masses tended to be towards the blue spectrum (lower velocities); 39.5% (17/43) of predominantly blue masses were malignant, compared to 14.3% (1/7) of red lesions.ConclusionsQuantitatively and qualitatively there is no statistically significant association between shear wave velocity and malignancy. There is no clear additional role to B-mode imaging currently.Key Points• Correlation between shear wave velocity and soft tissue malignancy was statistically insignificant• B-mode ultrasound is 76.9 % sensitive and 78.8 % specific• Statistical models show elastography does not significantly add to lesion assessment

Perfusion pattern and time of vascularisation with CEUS increase accuracy in differentiating between benign and malignant tumours in 216 musculoskeletal soft tissue masses

IntroductionMusculoskeletal Soft Tissue Tumours (STT) are frequent heterogeneous lesions. Guidelines consider a mass larger than 5cm and deep with respect to the deep fascia potentially malignant. Contrast Enhanced Ultrasound (CEUS) can detect both vascularity and tumour neoangiogenesis. We hypothesised that perfusion patterns and vascularisation time could improve the accuracy of CEUS in discriminating malignant tumours from benign lesions. Materials and methods216 STT were studied: 40% benign lesions, 60% malignant tumours, 56% in the lower limbs. Seven CEUS perfusion patterns and three types of vascularisation (arterial-venous uptake, absence of uptake) were applied. Accuracy was evaluated by comparing imaging with the histological diagnosis. Univariate and multivariate analysis, Chi-square test and t-test for independent variables were applied; significance was set at p<0.05 level, 95% computed CI. ResultsCEUS pattern 6 (inhomogeneous perfusion), arterial uptake and location in the lower limb were associated with high risk of malignancy. CEUS pattern has PPV 77%, rapidity of vascularisation PPV 69%; location in the limbs is the most sensitive indicator, but NPV 52%, PPV 65%. The combination of CEUS-pattern and vascularisation has 74% PPV, 60% NPV, 70% sensitivity. No correlation with size and location in relation to the deep fascia was found. ConclusionUS with CEUS qualitative analysis could be an accurate technique to identify potentially malignant STT, for which second line imaging and biopsy are indicated in Referral Centers. Intense inhomogeneous enhancement with avascular areas and rapid vascularisation time could be useful in discriminating benign from malignant SST, overall when the lower limbs are involved.

Sonography of musculoskeletal soft-tissue masses: techniques, pearls, and pitfalls.

The purpose of this article is to review the appropriate use of ultrasound in the workup of soft-tissue masses of the extremities. The normal sonographic appearance of superficial soft tissues, the importance of proper technique in image acquisition, and the characteristic sonographic appearance of certain masses and potential pitfalls are discussed. Ultrasound is increasingly being used for the initial evaluation of soft-tissue masses of the extremities. Certain clinical and imaging findings allow diagnosis of selected soft-tissue masses; however, most imaging findings are nonspecific, and further evaluation is necessary. The many potential pitfalls can lead to adverse patient outcomes.

Diagnostic impact of echo planar diffusion-weighted magnetic resonance imaging (DWI) in musculoskeletal neoplastic masses using apparent diffusion coefficient (ADC) mapping as a quantitative assessment tool

PurposeTo evaluate the diagnostic impact of echo planar DW imaging in distinguishing benign from malignant musculoskeletal soft-tissue masses using ADC mapping as a quantitative assessment tool. Patients and methodsWe evaluated 73 tumors (21 bone tumors and 52 soft-tissue tumors). MR examinations were performed with a 1.5-T system. Diffusion-weighted single-shot EPI images were obtained in all patients. Apparent diffusion coefficients (ADCs) were calculated by using b factors of 0 and 1000s/mm2. ADC value measurements were compared with the histopathological findings. ResultsThe average ADC of benign tumors was 1.86±0.67×10−3mm2/s, and that of malignant soft-tissue tumors was 0.97±0.35×10−3mm2/s. ADC value of malignant tumors was significantly lower than that of the benign tumor group (p<0.0001). The highest ADC value was seen in the case of ganglion cyst (2.8±0.23×10−3mm2/s) and cystic neurofibroma (2.5±0.04×10−3mm2/s), and juxta cortical enchondroma (2.65±0.36×10−3mm2/s) while the lowest one was seen in aggressive fibromatosis (0.37±0.05×10−3mm2/s). For malignant soft-tissue masses, the highest ADC value was seen in mesenchymal chondrosarcoma (2.1±0.32) liposarcoma (intermediate grade) (1.4±0.21) while the lowest ADC value was seen in fibrosarcoma (high grade) (0.78±0.14). ConclusionMR diffusion provides additional information to the routine MRI sequences rendering it an effective non-invasive tool in differentiating between benign and malignant soft-tissue tumors.

Abstract No. 154: The adequacy and diagnostic accuracy of ultrasound guided percutaneous core needle biopsies in musculoskeletal soft tissue masses

Abstract No. 154: The adequacy and diagnostic accuracy of ultrasound guided percutaneous core needle biopsies in musculoskeletal soft tissue masses

Ultrasound of musculoskeletal soft tissue masses

AbstractSoft tissue masses have a varied presentation. Though all masses cannot be optimally imaged on USG, its easy availability, real-time capability, and cost-effectiveness, as well as the freedom it provides to examine in any direction, make it an automatic choice as a first-line modality. Though Doppler is an exciting modality, it has its limitations and is not always rewarding. USG is more useful for superficially located masses. The role of USG is to provide information about the extent of the mass, its nature, and its relationship to the surrounding structures. One important aim is to differentiate between a pseudotumor and a true mass lesion. Doppler can provide additional information in selected cases. USG can play a pivotal role in guiding a needle for obtaining a sample for tissue diagnosis. Benign lesions are more common than malignant ones, in day-to-day practice. As with any other musculoskeletal examination, technical expertise and a sound knowledge of musculoskeletal anatomy are important.

Sonographic Evaluation of the Musculoskeletal Soft Tissue Masses

This article describes the sonographic appearance of a variety of soft tissue masses. We review the current indications for performing musculoskeletal sonography as a screening and diagnostic tool in the clinical management of soft tissue masses.

Spectral Doppler sonography of musculoskeletal soft tissue masses.

To determine whether resistive indices obtained from spectral Doppler waveforms can be used to distinguish benign from malignant musculoskeletal soft tissue masses. A retrospective review of Doppler sonograms was performed for 52 patients with 53 soft tissue masses. All masses showed internal flow on color or power Doppler sonography, and spectral Doppler sonography yielded waveforms from which resistive indices were calculated. This information was analyzed along with the histologic diagnosis of each lesion with significance set at P > .05. There were 19 benign lesions and 34 malignancies. The resistive indices of the benign masses ranged from 0.44 to 1.0 (mean +/- SD, 0.72 +/- 0.42), whereas the malignant masses had resistive indices ranging from 0.28 to 1.0 (mean, 0.62 +/- 0.36). There was no statistically significant (P > .05) difference between the resistive indices of benign and malignant lesions. Resistive indices cannot be used to distinguish benign from malignant musculoskeletal soft tissue masses.