Differentiation of malignant and benign musculoskeletal tumors: combined color and power Doppler US and spectral wave analysis

[Interdisciplinary Treatment Of Tumorous And Tumour-Like Lesions Of Peripheral Nerves]

Tumorous or tumour-like lesions of peripheral nerves are generally rare, heterogeneous and challenging to diagnose and treat. They may become apparent by a palpable swelling (lump) near nerves, sensory and/or motor deficits, pain to touch or neuropathic pain. In 91% of cases, tumours are benign. The differentiation of entities and their characteristics as well as a function-preserving resection strategy are highly relevant. Misdiagnosis and inadequate treatment can lead to severe deficits and pain syndromes. Benign tumours include schwannomas and neurofibromas, which can occur sporadically but can also be associated with neurogenetic tumour disposition syndromes if they occur more frequently. Rarer benign nerve tumours include perineuriomas, lipomas, aggressive fibrosis (desmoid tumours), paragangliomas and haemangiomas. Ganglion cysts are described as tumour-like lesions. The association of nerve tumours with neurogenetic syndromes and the correct classification of potentially malignant lesions such as MPNST (malignant peripheral nerve sheath tumour) or intermediate stages such as ANNUBPs (atypical neurofibromatous neoplasms with unknown biological potential) pose particular challenges. Interdisciplinarity is highly relevant for clinical treatment and a correct diagnosis. The aim of our work is to provide an overview of the relevant entities, diagnostic evaluation and contemporary treatment strategies based on the current data situation and taking into account the recently published interdisciplinary AWMF S2k guideline "Diagnosis and Treatment of Peripheral Nerve Tumours".

Practical approach to ultrasound of soft tissue tumors and the added value of MRI: how I do it

This review outlines a practical approach to the everyday assessment of both non-neoplastic and neoplastic soft tissue tumors, focusing on ultrasound examination, though emphasizing the added benefit of magnetic resonance imaging in certain instances. Ultrasound approach and assessment, practical scenarios, reporting, biopsy, and follow-up are covered, as well as the criteria used to distinguish benign from malignant tumors. The potential benefits and current limitations of elastography and contrast-enhanced ultrasound in assessment are also addressed. Examples of commonly encountered soft tissue tumors are shown. Ultrasound can characterize most soft tissue masses based on their ultrasound appearance alone. Following ultrasound examination, three potential scenarios usually exist in clinical practice: (a) confident regarding diagnosis, (b) indeterminate mass with no evidence of malignancy, and (c) indeterminate mass with possibility of malignancy. A diagnostic pathway for each of these scenarios is provided. Magnetic resonance imaging is generally not helpful in further characterizing masses which are indeterminate on ultrasound assessment, though it is helpful in addressing other issues such as exact tumor location and neurovascular bundle involvement that may not be fully resolved on ultrasound examination. In these situations, magnetic resonance imaging examination can be tailored to address those specific questions that have not been adequately addressed on ultrasound examination. In this sense, both examinations are highly complementary. Tips for undertaking magnetic resonance imaging examinations are provided.

Ultrasonography of Superficial Soft-Tissue Masses: Society of Radiologists in Ultrasound Consensus Conference Statement

The Society of Radiologists in Ultrasound convened a panel of specialists from radiology, orthopedic surgery, and pathology to arrive at a consensus regarding the management of superficial soft-tissue masses imaged with US. The recommendations in this statement are based on analysis of current literature and common practice strategies. This statement reviews and illustrates the US features of common superficial soft-tissue lesions that may manifest as a soft-tissue mass and suggests guidelines for subsequent management.

Diagnosis and treatment of hand tumors

Hand tumors are a very common problem in hand surgery. While these lesions are most often benign, malignant lesions often have an atypical presentation and are discovered late, very often during an inappropriate treatment. To optimize the care of hand tumors and to reduce diagnostic and treatment errors, we will review the broad diagnostic and therapeutic principles and the most common clinical presentations.

Problem Solved: Integral Applications of Musculoskeletal Ultrasound

Musculoskeletal ultrasound has grown substantially in use over the past several years as an indispensable companion to magnetic resonance imaging and other imaging modalities. This article reviews 10 integral applications of musculoskeletal ultrasound as a problem-solving tool with correlative case examples. These applications include the following: (1) accessibility and portability, (2) targeted imaging, (3) dynamic imaging, (4) contralateral comparison, (5) Doppler imaging, (6) increased spatial resolution, (7) solid versus cystic comparison, (8) posttraumatic imaging, (9) postsurgical imaging, and (10) treatment delivery and optimization. The review will help the radiologist recognize the complementary uses of musculoskeletal ultrasound with radiography, computed tomography, and magnetic resonance imaging.

Utility of Preoperative Electrodiagnosis Together with Peripheral Nerve High-Resolution Ultrasound: A Complex Case Report of Neurofibromatosis Type I

Our case report underscores the importance of electroneuromyography (ENMG) combined with peripheral nerve high-resolution ultrasound (HRUS) in the evaluation of neurofibromatosis type 1 (NF1). A 49-year-old woman affected by NF1 came to our attention because of new-onset left arm weakness and atrophy. Debulking of a cervicothoracic C7-T1 neurofibroma had been performed 8 years earlier. On current admission, magnetic resonance imaging disclosed increased lesion volume that was thought to cause the neurologic deficits by compressing the C8 root. Findings from intraoperative neurophysiologic monitoring during repeat debulking suggested that C8 root integrity had been compromised during the first operation and that the new-onset symptoms probably stemmed from peripheral nervous system damage distal to the cervical roots. Postoperative ENMG showed chronic denervation signs in the muscles innervated by C7-C8-T1 roots, moderate carpal tunnel syndrome (CTS), and ulnar nerve conduction block at the elbow. HRUS confirmed the CTS and revealed multiple neurofibromas involving the distal tract of the radial, ulnar, and median nerves. Surgical debulking was considered unnecessary in this case. ENMG combined with nerve and plexus HRUS evaluation may help identify the cause of neurologic deficits and choose the best surgical option in such complex clinical conditions as NF1.

Soft Tissue Sarcomas

Imaging evaluation of soft tissue masses is essential for diagnosis, preoperative staging, and post-treatment follow-up. Magnetic resonance imaging plays the major role because of its superior resolution that helps in better tissue characterization, and its multiplanar imaging capability in evaluation of soft tissue masses. Additional imaging techniques, such as radiographs, computed tomography, positron-emission tomography-CT, radionuclide scintigraphy and ultrasonography, also play vital roles by providing additional information required in management of soft tissue masses. Knowledge of the usefulness and limitations of these imaging techniques is essential for their judicious selection. This article reviews the current role of various imaging techniques in diagnosis, presurgical planning, and post-treatment follow-up of soft tissue masses.

Power Doppler in musculoskeletal ultrasound: uses, pitfalls and principles to overcome its shortcomings

Power Doppler (PD) is used widely in musculoskeletal ultrasound, especially in the assessment of structures for evidence of inflammation and in evaluating soft tissue neoplasms. We reinforce and delineate the three cardinal principles of optimising PD assessment in order to avoid false positive or false negative results; namely (1) Optimal gain settings (2) Adequate transducer pressure, and (3) Proper patient/anatomical structure-of-interest positioning with complete tissue relaxation.

Accuracy of ultrasound in the characterisation of deep soft tissue masses: a prospective study

PURPOSE

To investigate the accuracy of ultrasound in characterising the type of mass and likelihood of malignancy in deep soft tissue masses.

METHODS

Five hundred seventy-nine deep soft tissue masses were prospectively studied by ultrasound. Masses (n = 137) with prior MRI or CT were not included. Following ultrasound examination, the likely nature of the mass as well as the confidence of the reporting radiologist ('fully confident' versus 'not fully confident') about the ultrasound diagnosis was recorded. Clinical and ultrasound diagnoses were compared with the histological diagnosis which was available in 134 (23%) of the 579 masses.

RESULTS

Compared with histology, clinical and ultrasound accuracy for characterising the type of mass were 47% and 88% respectively when all differential diagnoses were considered. The radiologist was fully confident regarding the type of 436 (75%) of 579 masses and, in this setting, for those cases that could be compared with histology, diagnostic accuracy was 96%. For the remaining masses, where the radiologist was not fully confident, accuracy compared with histology was 58% for the first differential diagnosis and 80% for all differential diagnoses. For identifying malignancy, sensitivity, specificity, and positive and negative predictive value of ultrasound were 97%, 58%, 67%, and 99% respectively. Ultrasound alone was considered sufficient for diagnostic workup in over half of all deep soft tissue masses.

CONCLUSION

Ultrasound is useful at characterising and recognising malignancy in deep soft tissue masses. Provided local practice patterns are favourable, ultrasound may be considered a first-line investigation in the diagnostic workup of deep soft tissue masses.

KEY POINTS

• In three-quarters of cases, one can be fully confident about characterising the nature of deep soft tissue masses on ultrasound and, for those fully confident cases that could be compared with histology, the diagnostic accuracy of ultrasound was 96%. • Ultrasound can correctly recognise nearly all malignant deep soft tissue masses but some benign masses will also be considered possibly malignant. • Ultrasound alone was considered sufficient for imaging workup in over half of deep soft tissue masses.

Contrast-Enhanced Ultrasound for Musculoskeletal Applications: A World Federation for Ultrasound in Medicine and Biology Position Paper

This World Federation for Ultrasound in Medicine and Biology position paper reviews the diagnostic potential of ultrasound contrast agents for clinical decision-making and provides general advice for optimal contrast-enhanced ultrasound performance in musculoskeletal issues. In this domain, contrast-enhanced ultrasound performance has increasingly been investigated with promising results, but still lacks everyday clinical application and standardized techniques; therefore, experts summarized current knowledge according to published evidence and best personal experience. The goal was to intensify and standardize the use and administration of ultrasound contrast agents to facilitate correct diagnoses and ultimately to improve the management and outcomes of patients.

Accuracy of ultrasound in the characterization of superficial soft tissue tumors: a prospective study

OBJECTIVE

To prospectively evaluate the accuracy of ultrasound in defining the specific nature of superficial soft tissue masses as well as determining malignancy.

MATERIALS AND METHOD

Eight hundred twenty-three superficial soft tissue masses were prospectively evaluated with ultrasound by one of five experienced musculoskeletal radiologists. The radiologist at the time of examination provided one to three specific differential diagnoses and the perceived level of confidence with regard to each diagnosis. Clinical and ultrasound diagnoses were compared with the histological diagnosis to determine accuracy. Tumor malignancy was determined by histology or clinical/imaging follow-up.

RESULTS

Histological correlation was present for 219 (26.6%) of the 823 masses. Compared with histology, the accuracy of clinical and ultrasound examination for determining specific tumor type was 25.6% and 81.2% respectively considering all differential diagnoses provided. Radiologists were "fully confident" with the ultrasound diagnosis in 585 (71.1%) of 823 masses overall. In this setting, when compared with histology, the diagnostic accuracy of ultrasound was 95.5%. When the radiologist was "not fully confident," accuracy was 41.3% for the first differential diagnosis and 60.9% for all differential diagnoses. Diagnostic accuracy improved with increasing radiologist experience. Sensitivity, specificity, positive predictive value, and negative predictive value of ultrasound for identifying malignant tumor were 93.3%, 97.9%, 45.2%, and 99.9% respectively.

CONCLUSIONS

One can be "fully confident" at characterizing over two-thirds of superficial soft tissue masses based on ultrasound appearances and, in this setting, diagnostic accuracy is very high. Ultrasound examination is also highly accurate at discriminating benign from malignant superficial soft tissue masses.

Role of high-resolution ultrasound in detection and monitoring of peripheral nerve tumor burden in neurofibromatosis in children

PURPOSE

Peripheral nerve sheath tumors are hallmark findings in neurofibromatosis types 1 and 2. With increasing size, they typically lead to neurological symptoms, and NF1 patients have a lifetime risk of 8-13% for developing malignant peripheral nerve sheath tumors. Medical imaging is therefore highly needed for early detection and exact localization of symptomatic or potentially malignant tumors. This review will give an overview of the ultrasound characteristics of peripheral nerve sheath tumors and findings in patients with neurofibromatosis types 1 and 2.

METHODS

A systematic search of electronic databases, reference lists, and unpublished literature was conducted including the keywords "schwannoma," "neurofibroma," "neurofibromatosis," "benign and malignant peripheral nerve sheath tumor."

RESULTS

The high-resolution allows a clear analysis of tumor echotexture, definition of margins, and the relation to the parent nerve. The use of color duplex/Doppler and contrast agent adds valuable information for the differentiation of benign and malignant tumors.

CONCLUSION

High-resolution ultrasound is a well-established, non-invasive, and easily repeatable first-line tool in diagnostic procedures of soft tissue tumors.

Ultrasonographic Features of Eccrine Spiradenoma

The purpose of this series was to evaluate the features of eccrine spiradenoma on ultrasonography (US). We reviewed the clinical data of 8 patients with eccrine spiradenoma who underwent preoperative US at 4 different medical institutions from 2004 to 2016 and analyzed the US features in terms of the tumor location, size, shape, margin, echo texture, echogenicity, posterior acoustic enhancement, calcification, septum, and color Doppler flow. There were 7 female patients and 1 male patient. The mean patient age was 45.6 years (range, 28-60 years). Most of the tumors were located primarily in the subcutaneous fat layer. The mean size of the tumors was 14.3 mm. The masses had a lobular appearance in 7 patients and had a tractlike structure in 3 patients. In 6 patients, the masses had a heterogeneous echo texture. Six cases showed hypoechogenicity with more hypoechoic foci in the masses, and 2 cases showed hypoechogenicity only. Color Doppler flow was evaluated in 7 patients; the blood flow was central and peripheral in 4 patients and only peripheral in 3 patients. All cases showed posterior acoustic enhancement and had well-defined margins. Calcification and septa were not seen in any cases. Eccrine spiradenoma is usually located in the subcutaneous fat layer, has a well-defined margin, a lobulated appearance, occasionally with a tractlike structure, a heterogeneous echo texture, a hypoechoic appearance with internal hypoechoic foci and posterior acoustic enhancement, and shows blood flow in the peripheral portion, with or without blood flow in the central portion.

[Ultrasound-guided interventions on the peripheral nervous system]

CLINICAL/METHODICAL ISSUE

Up to the advent of high-resolution ultrasound, interventions on the peripheral nervous system, including local anesthesia and pain treatment were performed without visual guidance, which in some cases led to treatment failure or local tissue and nerve damage.

METHODICAL INNOVATIONS

Progress in the field of ultrasound has enabled the functional visualization, anesthesia and anti-inflammatory or neurolytic treatment of many peripheral nerves, such as the brachial plexus, nerves of the upper and lower extremities and various nerves of the trunk. Contrast medium-guided biopsies have also become feasible.

ACHIEVEMENTS

This article discusses the general prerequisites for such interventions and details the visualization and the interventional algorithms for interventions on the brachial plexus, on large nerves often affected by compression neuropathies, such as the median, ulnar, sciatic and femoral nerves and small nerves, such as the lateral cutaneous nerves of the thigh. Furthermore, contrast medium-aided biopsies of intraneural and perineural masses are discussed. Finally, the treatment of stump neuromas via phenol instillation is described.

PRACTICAL RECOMMENDATIONS

Innovations in high-resolution ultrasound allow the reliable and safe diagnosis and treatment of various pathologies of the peripheral nervous system with few side effects. Compared to older methods, which did not use visual guidance ultrasound provides higher success rates and lower adverse event rates in many instances.

Preoperative Ultrasonographic Evaluation for Malignancy of Soft-Tissue Sarcoma: A Retrospective Study

Background:

Ultrasonography is useful for distinguishing between benign and malignant soft-tissue tumors. However, no study has focused on its usefulness in the differential diagnosis between low-grade and high-grade soft-tissue sarcomas. We conducted a retrospective study to determine the usefulness of the parameters of ultrasonograph and to develop a practical scoring system for distinguishing between high-grade and low-grade sarcomas.

Methods:

Twenty-two cases of low-grade and 43 cases of high-grade malignant soft-tissue sarcoma were enrolled. Ultrasonography parameters including the longest diameter, depth of the tumor, echogenicity, tumor margin, and vascularity defined according to Giovagnorio’s criteria were analyzed as factors to distinguish between the two types of sarcoma. Significant factors were entered into a multivariate model to define the scores for distinction according to the odds ratio. The usefulness of the score was analyzed via receiver operating characteristic analyses.

Results:

In univariate analysis, tumor margin, echogenicity, and vascularity were significantly different between low- and high-grade sarcomas. In the multivariate regression model, the odds ratio for high-grade vs. low-grade sarcoma was 8.8 for tumor margin, 69 for echogenicity, and 8.3 for vascularity. Scores for the risk factors were defined as follows: 1, ill-defined margin; 2, hypoechoic echogenicity; and 1, type IV in Giovagnorio’s criteria. The sum of each score was confirmed by receiver operating characteristic analysis. The area under the curve was 0.95, with a cut-off score of 3, indicating that the scoring system was useful.

Conclusion:

The ultrasonography parameters of tumor margin, echogenicity, and vascularity are useful for distinguishing between low- and high-grade sarcomas.

Preoperative evaluation of intraoperative blood loss during malignant soft tissue tumor resection by ultrasonography

BACKGROUND

Preoperative evaluation of the risk of surgery-related blood loss in malignant soft tissue tumor resection is difficult because of wide variations in histological subtype, malignancy, location, and size. Ultrasonography is useful for the evaluation of blood flow around a soft tissue tumor and has the potential to preoperatively estimate intraoperative blood loss in tumor resection. To date, there has been no report regarding blood loss evaluation using ultrasonography in this field.

PATIENTS AND METHODS

The usefulness of information obtained by ultrasonography, including tumor size, vessel density in the tumor, and blood flow volume in the vessels, was analyzed for the prediction of intraoperative blood loss in malignant soft tissue tumor resection.

RESULTS

Vessel density in the tumor and blood flow in the vessels were identified as independent risk factors for blood loss. Using these factors, a new index for the prediction of blood loss was established. Receiver operating characteristic analyses revealed a high area under the curve value (0.80), confirming the accuracy of the index for the prediction of blood loss.

CONCLUSION

Ultrasonography is a useful modality for predicting intraoperative blood loss in malignant soft tissue tumor surgery.

Diagnostic Imaging Update: Soft Tissue Sarcomas

BACKGROUND

No single imaging approach is ideal for every tumor. While radiography can be effective for diagnosis of specific tumors, additional imaging is often required. Soft tissue sarcomas require a multimodality approach.

METHODS

The authors discuss the general imaging approaches for patients who present with soft tissue masses, the fundamental principles inherent to tumor imaging, and the specific applications of newer imaging modalities.

RESULTS

Magnetic resonance imaging has emerged as the preferred technique for evaluating soft tissue tumors but is limited in demonstrating the pattern of soft tissue calcification. Computed tomography is the best modality for evaluating osseous architecture and for patients who cannot be evaluated with MRI. PET is helpful in metabolic imaging, and ultrasonography is useful in differentiating cystic from solid masses. Magnetic resonance angiography accurately reveals the arterial and venous supply of vascular tumors.

CONCLUSIONS

Current imaging techniques provide numerous noninvasive methods to diagnose and stage suspected soft tissue sarcomas.

Diagnostic hierarchy of radiological features in soft tissue tumours and proposition of a simple diagnostic algorithm to estimate malignant potential of an unknown mass

OBJECTIVE

To quantify the diagnostic utility of imaging features in soft tissue masses (STMs) and to provide a ranked list of predictors for malignancy.

SUBJECTS AND METHODS

Imaging features in 260 cases of STMs with verified histology were assessed. Diagnostic properties including sensitivity, specificity, positive and negative predictive values, likelihood/odds ratios (OR) and normalized variance (NV) via random forest analysis were calculated. The diagnostic utility of an 8-item checklist consisting of the highest-ranked features was evaluated through a receiver-operating-characteristics (ROC) curve.

RESULTS

The most predictive features (NV/OR in parentheses) were heterogeneous contrast-enhancement in ultrasound (297.9/15.1) and MRI (197.3/11.9), lesion roundness (209.8/5.5), diffusion restriction (175.8/9.3), cystic/necrotic intralesional areas (167.1/8.3), higher patient age (159.0/2.6), surrounding oedema (155.4/6.5) and intralesional Doppler hypervascularity (134.4/5.1). A simple 8-item checklist was highly predictive of malignancy in cases with at least 75% positive features (0.90 area under the ROC curve, 87.0% sensitivity, 84.5% specificity, 59.5% positive and 96.1% negative predictive value, 36.5 odds ratio) even in cases with only partial feature availability.

CONCLUSION

Features vary widely in their diagnostic value in STMs; an 8-item checklist based on the eight most decisive features can be a simple tool to assess the likelihood for malignancy in unknown soft tissue masses, even though a stratified approach is certainly still advisable when first confronted with an STM.

Ultrasound assessment of peripheral nerve pathology in neurofibromatosis type 1 and 2

OBJECTIVE

The neurofibromatoses (NF) type 1 and 2 are hereditary tumor predisposition syndromes caused by germline mutations in the NF1 and NF2 tumor suppressor genes. In NF1 and 2, peripheral nerve tumors occur regularly. For further characterizing nerve ultrasound was performed in patients with NF1 and 2.

METHODS

Patients with established diagnosis of NF1 (n=27) and NF2 (n=10) were included. Ultrasound of peripheral nerves and cervical roots was performed during routine follow-up visits. Healthy volunteers were studied for comparison.

RESULTS

In patients with NF1, median cross-sectional area (CSA) of most nerves was significantly increased compared to controls and to NF2 due to generalized plexiform tumors, which arose out of multiple fascicles in 23 of 27 patients (85%). These were often accompanied by cutaneous or subcutaneous neurofibromas. In NF2, the overall aspect of peripheral nerves consisted of localized schwannomas (80%) and, apart from that, normal nerve segments.

CONCLUSION

Nerve ultrasound is able to visualize different nerve pathologies in NF1 and NF2. It is a precise and inexpensive screening method for peripheral nerve manifestation in neurofibromatosis and should be considered as the first choice screening imaging modality for all peripheral nerves within reach of non-invasive ultrasound techniques.

SIGNIFICANCE

Ultrasound patterns of peripheral nerve pathologies are described for the first time in a large cohort of patients with NF1 and NF2. It is a suitable screening tool and enables targeted MRI analysis.

Soft-Tissue Tumor Contrast Enhancement Patterns: Diagnostic Value and Comparison Between Ultrasound and MRI

OBJECTIVE

The purpose of this study was to assess and compare contrast-enhanced ultrasound and MRI patterns in the diagnosis of soft-tissue masses.

MATERIALS AND METHODS

Two hundred fifty-five consecutively registered patients with histologically confirmed soft-tissue masses were included in this retrospective study. The diagnostic properties of four predefined contrast enhancement (CE) patterns were assessed, and logistic regression analysis was performed to determine the correlation between diagnosis and CE pattern, lesion size, and patient age and sex. The influence of lesion size on the occurrence of inhomogeneous CE patterns in malignancies was also determined.

RESULTS

Homogeneous CE patterns were highly specific for benignity, and inhomogeneous CE was moderately specific for malignancy in both ultrasound and MRI. A combination of homogeneous and inhomogeneous CE patterns led to 88.3% and 88.7% sensitivity, 66.7% and 59.7% specificity, 73.4% and 68.2% correct classification, 54.6% and 47.8% positive predictive value, 92.6% and 92.7% negative predictive value, 2.65 and 2.20 positive likelihood ratio, and 0.18 and 0.19 negative likelihood ratio for contrast-enhanced ultrasound and contrast-enhanced MRI. Cases with homogeneous CE in either ultrasound or MRI also were predominantly benign. The occurrence of inhomogeneous CE in malignant lesions increased with size.

CONCLUSION

CE patterns in ultrasound and MRI offer additional information about the differentiation of an unknown soft-tissue mass. The results of this study showed that homogeneous or absent CE was specific for benign differentiation and that heterogeneous CE was linked to malignancy. The routine analysis of CE patterns should increase diagnostic reliability in unclear soft-tissue masses.

Intraoperative high-resolution ultrasound and contrast-enhanced ultrasound of peripheral nerve tumors and tumorlike lesions

The diagnostic workup and surgical therapy for peripheral nerve tumors and tumorlike lesions are challenging. Magnetic resonance imaging is the standard diagnostic tool in the preoperative workup. However, even with advanced pulse sequences such as diffusion tensor imaging for MR neurography, the ability to differentiate tumor entities based on histological features remains limited. In particular, rare tumor entities different from schwannomas and neurofibromas are difficult to anticipate before surgical exploration and histological confirmation. High-resolution ultrasound (HRU) has become another important tool in the preoperative evaluation of peripheral nerves. Ongoing software and technical developments with transducers of up to 17-18 MHz enable high spatial resolution with tissue-differentiating properties. Unfortunately, high-frequency ultrasound provides low tissue penetration. The authors developed a setting in which intraoperative HRU was used and in which the direct sterile contact between the ultrasound transducer and the surgically exposed nerve pathology was enabled to increase structural resolution and contrast. In a case-guided fashion, the authors report the sonographic characteristics of rare tumor entities shown by intraoperative HRU and contrast-enhanced ultrasound.

Ultrasonography of soft tissue "oops lesions"

In this article, I would like to define “oops lesions” as soft tissue mass-like lesions that involve surprise or embarrassment for radiologists following the final diagnosis. Examples of “oops lesions” include malignant tumors that appear benign, malignancy-mimicking benign tumors, incorrect identification of epidermal inclusion cysts, and soft tissue pseudotumors. Ultrasonography (US) findings are very helpful in the diagnosis of soft tissue tumors; however, the diagnosis of soft tissue tumors on the basis of US findings alone has some limitations. Therefore, clinical findings, laboratory data, findings from additional imaging modalities, and demographic data of patients should be considered together with US findings.

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

INTRODUCTION

Musculoskeletal Soft Tissue Tumours (STT) are frequent heterogeneous lesions. Guidelines consider a mass larger than 5 cm 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 METHODS

216 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.

RESULTS

CEUS 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.

CONCLUSION

US 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.

Contrast-enhanced color Doppler ultrasonography increases diagnostic accuracy for soft tissue tumors

Resolution of ultrasonography (US) has undergone marked development. Additionally, a new-generation contrast medium (Sonazoid) used for US is newly available. Contrast-enhanced US has been widely used for evaluating several types of cancer. In the present study, we evaluated the ability of color Doppler US (CDUS) and Sonazoid to differentiate between benign and malignant soft tissue tumors. A total of 180 patients (87 male, 93 female) were enrolled in the present study. The patient ages ranged from 1 to 91 years (mean 58.1±20.0 years). The maximum size, depth, tumor margins, shape, echogenicity and textural pattern were measured on gray-scale images. CDUS was used to evaluate the intratumoral blood flow with and without Sonazoid. Peak systolic flow velocity (Vp), mean flow velocity (Vm), resistivity index (RI) and pulsatility index (PI) of each detected intratumoral artery were automatically calculated with power Doppler US (PDUS). The present study included 118 benign and 62 malignant tumors. Statistical significances were found in size, depth, tumor margin and textural pattern but not in shape or echogenicity on gray-scale images. Before Sonazoid injection, CDUS findings showed 55% sensitivity, 77% specificity and 69% accuracy, whereas contrast-enhanced CDUS showed 87% sensitivity, 68% specificity and 74% accuracy. There were no statistically significant differences between malignant and benign tumors regarding the mean Vp, Vm, RI and PI values determined on PDUS. In conclusion, contrast-enhanced CDUS proved to be a reliable diagnostic tool for detecting malignant potential in soft tissue tumors.

Imaging evaluation of musculoskeletal tumors

In this chapter, we review different imaging modalities, including radiography, computed tomography (CT), magnetic resonance imaging (MRI), ultrasound, and nuclear medicine scintigraphy, and their application to musculoskeletal neoplasm. Advantages and limitations of each modality are reviewed, and suggestions for imaging approach are provided.

Effects of hypoxia on human cancer cell line chemosensitivity

Background

Environment inside even a small tumor is characterized by total (anoxia) or partial oxygen deprivation, (hypoxia). It has been shown that radiotherapy and some conventional chemotherapies may be less effective in hypoxia, and therefore it is important to investigate how different drugs act in different microenvironments. In this study we perform a large screening of the effects of 19 clinically used or experimental chemotherapeutic drugs on five different cell lines in conditions of normoxia, hypoxia and anoxia.

Methods

A panel of 19 commercially available drugs: 5-fluorouracil, acriflavine, bortezomib, cisplatin, digitoxin, digoxin, docetaxel, doxorubicin, etoposide, gemcitabine, irinotecan, melphalan, mitomycin c, rapamycin, sorafenib, thalidomide, tirapazamine, topotecan and vincristine were tested for cytotoxic activity on the cancer cell lines A2780 (ovarian), ACHN (renal), MCF-7 (breast), H69 (SCLC) and U-937 (lymphoma). Parallel aliquots of the cells were grown at different oxygen pressures and after 72 hours of drug exposure viability was measured with the fluorometric microculture cytotoxicity assay (FMCA).

Results

Sorafenib, irinotecan and docetaxel were in general more effective in an oxygenated environment, while cisplatin, mitomycin c and tirapazamine were more effective in a low oxygen environment. Surprisingly, hypoxia in H69 and MCF-7 cells mostly rendered higher drug sensitivity. In contrast ACHN appeared more sensitive to hypoxia, giving slower proliferating cells, and consequently, was more resistant to most drugs.

Conclusions

A panel of standard cytotoxic agents was tested against five different human cancer cell lines cultivated at normoxic, hypoxic and anoxic conditions. Results show that impaired chemosensitivity is not universal, in contrast different cell lines behave different and some drugs appear even less effective in normoxia than hypoxia.

Ultrasound evaluation of superficial lumps and bumps of the extremities in children: a 5-year retrospective review

Ultrasonography is commonly requested for evaluation of palpable soft-tissue masses of the extremities in children. Although malignancy is quite rare in these children, it remains a primary diagnostic concern. As a result, knowledge of the common and uncommon soft-tissue lesions as well as sonographic techniques for optimized evaluation are crucial for accurate assessment. This review describe the sonographic imaging appearance of the most commonly encountered superficial soft-tissue lesions at a tertiary academic pediatric hospital. Features of malignancy and findings warranting further evaluation such as lesion size, heterogeneity, vascularity and depth of involvement are also discussed.

Contrast-enhanced ultrasound findings in soft-tissue lesions: preliminary results

OBJECTIVES

There is currently no widely available, minimally invasive first-level examination that allows physicians to identify soft-tissue lesions that are likely to be malignant. The aim of this pilot study was to explore the potential suitability of dynamic contrast-enhanced ultrasound (DCE-US) for this purpose.

MATERIALS AND METHODS

23 patients were referred to the Veneto Oncological Institute for work-up of superficial soft-tissue lesions. Fourteen lesions were examined with CEUS and enhancement kinetics was analyzed. Subsequently, all lesions were surgically removed and subjected to histological analysis.

RESULTS

The 14 lesions included in the study were histologically classified as malignant (n = 7) or benign (n = 7, including 3 schwannomas). A statistically significant difference between benign and malignant lesions was found in terms of mean times to peak enhancement intensity (p = 0.03) but not mean filling times (FT). When schwannomas were analyzed as a separate group, their mean FT was found to be significantly different from that of the other benign lesions (p = 0.001) and from that of the group comprising other benign lesions as well as malignant lesions (p < 0.005).

CONCLUSIONS

CEUS with analysis of contrast-enhancement kinetics is a relatively low-cost, minimally invasive imaging technique, which appears to be a potentially effective first-level method for identifying suspicious soft-tissue masses.

Tumours and pseudotumours of the soft tissue in adults: perspectives and current role of sonography

Soft tissue tumours of the musculoskeletal system are reported relatively frequently. The quality of the information gained from different imaging modalities (Doppler sonography, multislice CT, MRI spectroscopy, and diffusion MRI) means that in a growing number of situations, we can envisage determining with great accuracy not only the usual information of tumour size and topography, but often the exact nature of the tissue, almost always identifying whether a lesion is aggressive or not. Of all these techniques, Doppler sonography has become the most widely used due to the striking improvements in its sensors, especially for superficial applications. Some other recent developments are: panoramic imaging, elastography (although its current contribution is still to be determined but it seems to offer promising potential), and, most importantly, specific contrast agents. These techniques have considerably refined the quality of the information obtained, and have particularly enhanced the degree of sensitivity with which lesion progression can be assessed. Ultrasonography is the very first investigation in our protocol. It is also very often used to close investigations, as it accurately guides core needle biopsy from these generally accessible lesions. The purpose of this article is to bring together updated information on the various collections of sonographic features seen in soft tissue tumours and pseudotumours and to emphasise the considerable contributions of these new technological developments, in particular contrast-enhanced sonography. The discussion will follow the World Health Organisation's anatomical pathology classifications of soft tissue tumours. We will close with a synthesis that summarises the main steps in our diagnostic process.

Musculoskeletal tumors: how to use anatomic, functional, and metabolic MR techniques

Although the function of magnetic resonance (MR) imaging in the evaluation of musculoskeletal tumors has traditionally been to help identify the extent of disease prior to treatment, its role continues to evolve as new techniques emerge. Conventional pulse sequences remain heavily used and useful, but with the advent of chemical shift imaging, diffusion-weighted imaging, perfusion imaging and MR spectroscopy, additional quantitative metrics have become available that may help expand the role of MR imaging to include detection, characterization, and reliable assessment of treatment response. This review discusses a multiparametric approach to the evaluation of musculoskeletal tumors, with a focus on the utility and potential added value of various pulse sequences in helping establish a diagnosis, assess pretreatment extent, and evaluate a tumor in the posttreatment setting for recurrence and treatment response.

Peripheral nerve sheath tumors. Benign or malignant? The role of MRI and ultrasonography in a case report

A 31-year-old male patient admitted to another hospital for investigation of a localized painful hump in the medial surface of his left leg. The clinical examination revealed a painful palpable lump in the medial surface of left thigh that was initially thought to be a hematoma due to a history of recent trauma. However, an ultrasound was requested to exclude deep venous thrombosis (DVT). The US examination revealed a heterogeneous, fusiform lesion with elongated proximal and distal projections in close proximity to superficial femoral artery and vein and could not definitely exclude the DVT hypothesis. In a second ultrasound examination performed in our department, a neurogenic origin of the lesion was proposed. A consequent MRI examination confirmed the presence of a fusiform tumor in the anatomic path of the saphenous nerve. This was further confirmed intraoperatively, and pathologically was diagnosed as a malignant peripheral nerve sheath tumor (MPNST). In this present study the role of ultrasonography, the correlation between MRI and ultrasonographic findings are discussed and a review of the literature is presented.

Color Doppler ultrasonography evaluation for chemotherapy treatment response of osteogenic sarcoma

The aim of this study was to evaluate the vascular parameters of the proximal peripheral arteries of limbs by color Doppler ultrasonography (CDUS) in individuals with osteogenic sarcoma (OGS) after neoadjuvant chemotherapy and their relation to the tumor necrosis rate. We recruited 50 individuals with osteogenic sarcoma who were scheduled for neoadjuvant chemotherapy before elective surgery from 2003 to 2010. Once enrolled, we evaluated these 50 subjects using color Doppler sonography to identify vascular parameters of tumor vessels before and after neoadjuvant therapy. The vascular parameters of the proximal peripheral arteries of limbs (peak systolic velocity [PSV], end-diastolic velocity [EDV], resistive index [RI]) and tumor neovascularity were compared before and after neoadjuvant chemotherapy using CDUS. Before chemotherapy, the PSV, EDV and RI differed significantly between the diseased and contralateral normal limbs (p < 0.001). Among the factors relating to the tumor necrosis rate before chemotherapy, the EDV of the diseased limb (p = 0.047) and tumor neovascularity (p = 0.027) showed significant differences. After chemotherapy, the PSV of the diseased limb (p = 0.022) and the difference in PSV between the diseased and contralateral limbs (p = 0.003) showed significant differences. The vascular parameters of the proximal peripheral arteries of limbs owing to tumor burden differ significantly between the diseased and contralateral normal limbs. For individuals with osteogenic sarcoma who still have a higher difference in PSV between the diseased and contralateral limbs after chemotherapy, another course of chemotherapy after surgery and close follow-up should be considered.

Intraoperative ultrasound assistance for excision of impalpable musculoskeletal soft tissue tumors

Intraoperative ultrasonography is a useful tool for the detection and extirpation of liver metastases, breast masses, and melanoma. However, the efficacy of this technology in intraoperative localization and resection of small soft tissue tumors has not been addressed. The purpose of this study is to report on the efficacy of intraoperative ultrasound assistance in excising impalpable musculoskeletal soft tissue tumors. Twenty-two soft tissue tumors <3 cm (range, 0.7-3 cm) were resected with intraoperative ultrasound assistance. All tumors were localized in the deep panniculus, fascia, or muscle. Surgical time and length of incisions was recorded in all the cases. Intra- and postoperative reregistration was made to confirm the tumor resection. Ultrasound assistance was successful in obtaining an accurate localization in all treated cases. Mean surgical time was 30 minutes (range, 13-87 minutes). Average incision length was 5.7 cm (range, 2.5-10.6 cm). Reregistration allowed intraoperative confirmation of the adequacy of the excision. The procedure allowed recognized and excised additional nodules not previously diagnosed in 3 cases. Postoperative echography done in all patients confirmed complete extirpation of the tumors, and histopathology confirmed adequate margins obtained. Intraoperative ultrasound can be used as an efficient tool to localize and treat impalpable small soft tissue tumors.

Soft-tissue tumor differentiation using 3D power Doppler ultrasonography with echo-contrast medium injection

BACKGROUND

We aimed to evaluate the ability of 3-dimensional power Doppler ultrasonography to differentiate soft-tissue masses from blood flow and vascularization with contrast medium.

METHODS

Twenty-five patients (mean age, 44.1 years; range, 12-77 years) with a palpable mass were enrolled in this study. Volume data were acquired using linear and convex 3-dimensional probes and contrast medium injected manually by bolus. Data were stored and traced slice by slice for 12 slices. All patients were scanned by the same senior sonologist. The vascular index (VI), flow index (FI), and vascular-flow index (VFI) were automatically calculated after the tumor was completely traced. All tumors were later confirmed by pathology.

RESULTS

The study included 8 benign (mean, 36.5 mL; range, 2.4-124 mL) and 17 malignant (mean, 319.4 mL; range, 9.9-1,179.6 mL) tumors. Before contrast medium injection, mean VI, FI and VFI were, respectively, 3.22, 32.26 and 1.07 in benign tumors, and 1.97, 29.33 and 0.67 in malignant tumors. After contrast medium injection, they were, respectively, 20.85, 37.33 and 8.52 in benign tumors, and 40.12, 41.21 and 17.77 in malignant tumors. The mean differences between with and without contrast injection for VI, FI and VFI were, respectively, 17.63, 5.07 and 7.45 in benign tumors, and 38.15, 11.88 and 16.55 in malignant tumors. Tumor volume, VI, FI and VFI were not significantly different between benign and malignant tumors before and after echo-contrast medium injection. However, VI, FI and VFI under self-differentiation (differences between with and without contrast injection) were significantly different between malignant and benign tumors.

CONCLUSION

Three-dimensional power Doppler ultrasound is a valuable tool for differential diagnosis of soft-tissue tumors, especially with the injection of an echo-contrast medium.

Soft tissue tumours: imaging strategy

Vascular tumours and malformations, fibrous and fibrohistiocytic tumours and pseudotumours are the most common benign soft-tissue masses observed in children, and can be treated conservatively. Rhabdomyosarcomas are the most frequent malignant tumours, accounting for about half of soft tissue sarcomas. A child referred for a soft-tissue mass should ideally be managed by a multidisciplinary team and primary excision should be proscribed until a definite diagnosis has been established. Clinical examination, conventional radiography and US with Doppler represent the first-line examinations and are sometimes sufficient to make a diagnosis. In all other situations, MRI is mandatory to establish the aggressiveness and extension of the tumour. This technique provides the relevant data to guide the decision regarding tissue sampling.

Distinguishing between primary endocervical and endometrial adenocarcinomas: is a 2-marker (Vim/CEA) panel enough?

Gynecological pathologists are used to operating many panels of various markers in combination for the diagnostic distinction between primary endocervical and endometrial adenocarcinomas. The conventional 3-marker (ER/Vim/CEA) panel is the most promising tool. In this study, our aim is to investigate whether a 2-marker panel is enough to distinguish between these two gynecologic malignancies. Additionally, we wish to determine which one is the most favorable among eight panels tested, including six 2-marker (ER/CEA, PR/CEA, Vim/CEA, ER/p16(INK4a), PR/p16(INK4a), Vim/p16(INK4a)) and two 3-marker (ER/Vim/CEA, ER/Vim/p16(INK)) panels. A tissue microarray was constructed using paraffin-embedded, formalin-fixed tissues from 35 hysterectomy specimens, including 14 primary endocervical adenocarcinomas and 21 primary endometrial adenocarcinomas. Utilizing the avidin-biotin complex (ABC) method, tissue array sections were immunostained with five commercially available antibodies (ER, Vim, CEA, PR, and p16(INK4a)) to evaluate their individual frequencies of expression. We found that all eight aforementioned panels showed an encouraging range of overall accuracy (69.2% to 78.3%). However, one panel of 2-markers (Vim, CEA) exhibited the most efficiency (78.3%) in the diagnostic distinction between primary endocervical and endometrial adenocarcinomas. Based on the analyzed data, we conclude that the 2-marker (Vim/CEA) panel seems adequate to be an appropriate, convenient, and efficient means to distinguish between primary endocervical and endometrial adenocarcinomas. Even though there were a limited number of cases, this study still provides valuable references to help avoid wasting resources and unnecessary marker testing.