Imaging Of Soft Tissue Sarcomas Research Articles

Virtual Biopsy in Soft Tissue Sarcoma. How Close Are We?

A shift in radiology to a data-driven specialty has been unlocked by synergistic developments in imaging biomarkers (IB) and computational science. This is advancing the capability to deliver “virtual biopsies” within oncology. The ability to non-invasively probe tumour biology both spatially and temporally would fulfil the potential of imaging to inform management of complex tumours; improving diagnostic accuracy, providing new insights into inter- and intra-tumoral heterogeneity and individualised treatment planning and monitoring. Soft tissue sarcomas (STS) are rare tumours of mesenchymal origin with over 150 histological subtypes and notorious heterogeneity. The combination of inter- and intra-tumoural heterogeneity and the rarity of the disease remain major barriers to effective treatments. We provide an overview of the process of successful IB development, the key imaging and computational advancements in STS including quantitative magnetic resonance imaging, radiomics and artificial intelligence, and the studies to date that have explored the potential biological surrogates to imaging metrics. We discuss the promising future directions of IBs in STS and illustrate how the routine clinical implementation of a virtual biopsy has the potential to revolutionise the management of this group of complex cancers and improve clinical outcomes.

Candidate Biomarkers for Specific Intraoperative Near-Infrared Imaging of Soft Tissue Sarcomas: A Systematic Review.

Simple SummaryNear-infrared imaging of tumors during surgery facilitates the oncologic surgeon to distinguish malignant from healthy tissue. The technique is based on fluorescent tracers binding to tumor biomarkers on malignant cells. Currently, there are no clinically available fluorescent tracers that specifically target soft tissue sarcomas. This review searched the literature to find candidate biomarkers for soft tissue sarcomas, based on clinically used therapeutic antibodies. The search revealed 7 biomarkers: TEM1, VEGFR-1, EGFR, VEGFR-2, IGF-1R, PDGFRα, and CD40. These biomarkers are abundantly present on soft tissue sarcoma tumor cells and are already being targeted with humanized monoclonal antibodies. The conjugation of these antibodies with a fluorescent dye will yield in specific tracers for image-guided surgery of soft tissue sarcomas to improve the success rates of tumor resections.Surgery is the mainstay of treatment for localized soft tissue sarcomas (STS). The curative treatment highly depends on complete tumor resection, as positive margins are associated with local recurrence (LR) and prognosis. However, determining the tumor margin during surgery is challenging. Real-time tumor-specific imaging can facilitate complete resection by visualizing tumor tissue during surgery. Unfortunately, STS specific tracers are presently not clinically available. In this review, STS-associated cell surface-expressed biomarkers, which are currently already clinically targeted with monoclonal antibodies for therapeutic purposes, are evaluated for their use in near-infrared fluorescence (NIRF) imaging of STS. Clinically targeted biomarkers in STS were extracted from clinical trial registers and a PubMed search was performed. Data on biomarker characteristics, sample size, percentage of biomarker-positive STS samples, pattern of biomarker expression, biomarker internalization features, and previous applications of the biomarker in imaging were extracted. The biomarkers were ranked utilizing a previously described scoring system. Eleven cell surface-expressed biomarkers were identified from which 7 were selected as potential biomarkers for NIRF imaging: TEM1, VEGFR-1, EGFR, VEGFR-2, IGF-1R, PDGFRα, and CD40. Promising biomarkers in common and aggressive STS subtypes are TEM1 for myxofibrosarcoma, TEM1, and PDGFRα for undifferentiated soft tissue sarcoma and EGFR for synovial sarcoma.

Functional imaging in soft tissue sarcomas: Update of the indications for 18F-FDG-PET/CT

Soft tissue sarcomas (STS) are a rare and heterogeneous group of tumors. They account for 1% of solid malignant tumors in adults and 7% in children and are responsible for 2% of cancer mortality. They require a multidisciplinary approach in centers with experience. This collaboration aims to update the scientific evidence to strengthen, together with clinical experience, the bases for the use and limitations of 18F-FDG-PET/CT in STSs. The general recommendations for the use of PET/CT in STS at present are summarized as the initial evaluation of soft tissue tumors when conventional image does not establish benignity with certainty and this determines the approach, in biopsy guiding in selected cases, in the initial staging, as additional tool, for rhabdomyosarcoma and STS of extremities or superficial trunk and head and neck tumors, in the suspicion of local recurrence when the CT or MRI are inconclusive and in the presence of osteosynthesis or prosthetic material and in assessment of therapy response to local/systemic therapy in stages ii/iii. In addition, PET/CT has the added value of being a surrogate marker of the histopathological response and it provides prognostic information, both in the baseline study and after treatment.

Imaging of soft tissue sarcomas.

Soft tissue sarcomas are rare and a heterogeneous group of neoplasms. Over the years imaging has played a crucial role in the initial staging, monitoring response to chemotherapy, and surveillance for recurrence. In the era of rapidly evolving individualized treatment due to evolving chemotherapies, increasing demand has been placed on the role of imaging in the management of this heterogeneous group. The rapidly evolving technologies in imaging are trying to keep up with the challenge, with development of newer strategies and hybrid imaging. However, many of these newer technologies are either not available or too costly, even in advanced countries, and hence their exact role remains uncertain. Due to this, and the vast diversity of sarcomas, the imaging appearance and management strategies vary and there is no universally accepted algorithm for the role of individual imaging technologies. The basic imaging techniques; however, remain the same, with these newer techniques and strategies vying for their roles in management. We review current imaging techniques and their role in the management of soft tissue sarcomas.

18F-FDG PET-CT in soft tissue sarcomas: staging, restaging, and prognostic value?

The aim of this article was to review the current role of PET/computed tomography (CT) in soft tissue sarcomas with respect to staging, restaging, and prognostic value. Fluorine-18-fluorodeoxyglucose PET, for instance, can be very useful in differentiating recurrent disease from scar tissue during follow-up. Other indications of PET-CT are still evolving, especially in the light of new molecular drugs. Different aspects of PET/CT imaging in soft tissue sarcomas are overviewed including organ-specific merits, limitations, and potential pitfalls. Finally, methodological considerations on PET/MRI are also briefly discussed.

Contemporary imaging of soft tissue sarcomas.

Imaging plays an important role in the diagnosis, biopsy, staging, and follow-up of patients with soft tissue sarcomas. General principles of imaging diagnosis of soft-tissue sarcomas using radiography, ultrasound, CT, MRI, and PET/CT will be discussed, with emphasis on the role of location, internal fat and calcification, presence of myxoid stroma, and enhancement characteristics.

9431 POSTER Whole-body-PET/MRI a New Way of Imaging in Soft Tissue Sarcomas

9431 POSTER Whole-body-PET/MRI a New Way of Imaging in Soft Tissue Sarcomas

Imaging of Soft Tissue Sarcomas

Imaging of Soft Tissue Sarcomas

Imaging of Soft Tissue Sarcomas

Soft-tissue sarcomas are encountered only infrequently, but their diagnosis is important because the long-term prognosis is usually good if the tumour is properly managed. The role of various imaging modalities in the evaluation of these neoplasms is discussed, with special emphasis on magnetic resonance imaging. The authors review the importance of imaging in tumour detection, characterization, staging and surveillance after therapy, and they emphasize the critical subject of proper biopsy technique.

Histology and imaging of soft tissue sarcomas

Imaging and histology are two complementary morphological techniques which play a fundamental role in the diagnosis and management of soft tissue sarcomas. Imaging allows to identify some pseudosarcomatous benign lesions such as myositis ossificans, intramuscular hemangioma, angiomyolipoma, intramuscular lipoma, giant cell tumour of tendon sheath, desmoid tumour and elastofibroma. There is no formal criterion for diagnosing a sarcoma on magnetic resonance imaging (MRI) but malignancy is strongly suspected with the presence of necrosis and vascular, bone or joint invasion. Imaging may also suggest some histological types of sarcoma such as well-differentiated liposarcoma, dedifferentiated liposarcoma, synovial sarcoma or extraskeletal osteosarcoma. Imaging is also extremely helpful in determining the appropriate kind of sampling to carry out and in guiding the performance of a microbiopsy. The appearance observed on imaging should always be taken into consideration for the interpretation of the microbiopsy by the pathologist.

Post-operative imaging of soft tissue sarcomas

Soft tissue sarcomas are uncommon malignancies that have a high risk of local recurrence despite adequate initial surgery. The aim of follow-up imaging with any malignancy is to detect recurrence promptly so that treatment can be instigated at the earliest possible opportunity. In this review article, we discuss the imaging modalities that can be employed to detect local recurrence following surgery for an extremity soft tissue sarcoma. The role of radiographs, computed tomography, magnetic resonance imaging and positron emission tomography is reviewed followed by a discussion on the imaging modalities useful in the detection of metastatic disease. Finally, we present a robust pathway that is suggested for the follow-up of patients with an extremity soft tissue sarcoma.

Imaging of soft-tissue sarcomas.

A multidisciplinary approach that includes active participation by a radiologist is beneficial for optimal diagnostic evaluation and treatment of soft-tissue sarcomas. Recent advances in diagnostic imaging include a better understanding of the practical roles of ultrasonography, computed tomography, and magnetic resonance imaging in the evaluation of primary and recurrent soft-tissue sarcomas. The potential role of positron emission tomography scanning and dynamic magnetic resonance imaging in the evaluation of soft-tissue sarcomas has been preliminarily evaluated. The clinically practical utility of radiologic imaging in the evaluation of soft-tissue sarcomas is discussed, and ongoing research is briefly reviewed.

Clinical value of [18-F]] fluorodeoxyglucose positron emission tomography imaging in soft tissue sarcomas.

To evaluate positron emission tomography (PET) using 2-fluoro-2-deoxy-D-glucose (FDG) for clinical application in soft tissue sarcomas. FDG PET is a promising noninvasive method for the preoperative assessment of soft tissue sarcomas and may complement radiologic tomography. Data from 50 consecutive patients with 59 masses, either suspicious for primary or locally recurrent soft tissue sarcoma, were prospectively gathered. The semiquantitative FDG uptake (standardized uptake values [SUVs]) was calculated in tumor and normal tissue (muscle). Histopathology of surgical specimens and follow-up data were used as control criteria. In primary soft tissue sarcomas, PET displayed a sensitivity of 91% and a specificity of 88%. Local recurrence was detected with a sensitivity of 88% and a specificity of 92%. All intermediate-grade and high-grade soft tissue sarcomas (primary and locally recurrent) were visualized with a precise differentiation from muscle. Fifty percent of the low-grade sarcomas showed an FDG uptake equivalent to muscle (false-negative results in one primary and three recurrent soft tissue sarcomas). Benign soft tissue tumors (e.g., lipoma, leiomyoma, ganglion) did not accumulate FDG. Inflammation resulted in an increased FDG uptake. The semiquantitative FDG uptake (SUVs) correlated with tumor grade but not with size and histologic type. High-grade and intermediate-grade soft tissue sarcomas are amenable to PET imaging, whereas low-grade lesions may not be depicted. SUVs for FDG correlate with tumor grade in soft tissue sarcomas. Benign soft tissue tumors are differentiated from higher-grade soft tissue sarcomas. These data show that FDG-PET can complement preoperative radiologic assessment for soft tissue sarcomas and that FDG-PET is a powerful diagnostic tool for detecting high-grade and intermediate-grade local recurrence.

Optimal radiologic imaging of soft tissue sarcomas.

Radiologic evaluation of the patient with soft tissue sarcoma may include conventional radiography, scintigraphy, ultrasonography (US), computed tomography (CT), and magnetic resonance (MR) imaging. The radiologist also plays a critical role in the evaluation of the patient with soft tissue sarcoma by guiding and performing aspiration biopsies. This review discusses the use of radiological techniques to evaluate the primary lesion and to detect recurrences. In adults, soft tissue sarcoma most commonly occurs in the extremities, and this review emphasizes the role of MR imaging in the pre- and post-treatment evaluation of extremity soft tissue sarcomas. The role of imaging studies in the evaluation of soft tissue sarcomas in the abdomen, thorax, and the head and neck region is also discussed.

Instructional Course Lectures, The American Academy of Orthopaedic Surgeons - New Developments in the Staging and Imaging of Soft-Tissue Sarcomas*†

New developments in staging have given greater importance to the imaging of soft-tissue sarcomas since the time of the last articles on soft-tissue tumors in the Instructional Course Lectures9,19 or even more recent reviews37. Whereas previous articles have focused on the diagnosis, treatment, and molecular biology of benign19 and malignant9 soft-tissue tumors, the current article will present a new modification of the staging system that has been proposed by the American Joint Committee on Cancer38. Imaging techniques and unique characteristics of soft-tissue tumors will be discussed in order to demonstrate how they are related to the new criteria for staging. The main purpose of staging a tumor is to determine a patient's prognosis and to help to direct treatment. Malignant tumors have been described as having a life cycle. Therefore, staging identifies specific time-points in a tumor's life cycle (Fig. 1). Staging is usually done at the time that a malignant tumor is diagnosed, but restaging may be performed if the disease progresses and the patient becomes a candidate for various treatment protocols or other clinical research trials46. Pathological criteria, such as the histological grade, amount of necrosis, and size of the tumor as determined at the time of excision, are commonly used for the staging of carcinomas of the skin, bowel, prostate, cervix, and so on. However, in the case of soft-tissue sarcomas, the initiation of treatment such as chemotherapy or radiation before the tumor is excised may alter such factors as the size of the tumor and the amount of necrosis, thus reducing the accuracy of pathological staging that is based on the resected tumor. Therefore, staging based on the pathological characteristics of the resected tumor has given way to staging based on both clinical factors (such …

Imaging of Soft Tissue Sarcomas

Imaging of soft tissue sarcomas is critically important in the management of these patients. Whether CT scanning or MR imaging is the best test remains controversial; studies to support either modality exist and are reviewed. An integrated approach using clinical algorithms and radiologic studies to preoperatively stage and follow these patients seems to provide optimal care.

Imaging of Hepatobiliary Neoplasms

Improvements in imaging have markedly improved the ability to detect hepatobiliary masses. The radiologic features of a lesion when considered in the context of the medical history, physical findings, and laboratory data can often provide a diagnosis. Investigative modalities can accurately stage hepatobiliary tumors and determine their resectability so that the patient may be offered appropriate therapeutic interventions. This article summarizes the essential imaging techniques and their application to common hepatobiliary neoplasms.

PET imaging in soft tissue sarcomas.

Positron emission tomography (PET) was conceived in the early years of nuclear medicine; however, until about 1980 the technology was insufficiently developed to allow its routine application. Furthermore, the high cost of construction and operation of a PET facility delayed its use in the clinical arena and also limited the number of sites available for its development. Today, only 15 years later, PET instrumentation is very sophisticated, costs are decreasing relative to other clinical studies, and clinical PET procedures are proliferating rapidly. In the last few years the application of PET to oncology has proven to be very successful, and there is now a significant literature on PET imaging of many different cancers [1–18].KeywordsPositron Emission TomographyLocal Cerebral Glucose UtilizationMalignant Fibrous HistiocytomasPositron Emission Tomography TechniquePositron Emission Tomography EvaluationThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.