Soft tissue tumor imaging in adults: whole-body staging in sarcoma, non-malignant entities requiring special algorithms, pitfalls and special imaging aspects. Guidelines 2024 from the European Society of Musculoskeletal Radiology (ESSR).

OBJECTIVES: The revised European Society of Musculoskeletal Radiology (ESSR) consensus guidelines on soft tissue tumor imaging represent an update of 2015 after technical advancements, further insights into specific entities, and revised World Health Organization (2020) and AJCC (2017) classifications. This second of three papers covers algorithms once histology is confirmed: (1) standardized whole-body staging, (2) special algorithms for non-malignant entities, and (3) multiplicity, genetic tumor syndromes, and pitfalls. MATERIALS AND METHODS: A validated Delphi method based on peer-reviewed literature was used to derive consensus among a panel of 46 specialized musculoskeletal radiologists from 12 European countries. Statements that had undergone interdisciplinary revision were scored online by the level of agreement (0 to 10) during two iterative rounds, that could result in 'group consensus', 'group agreement', or 'lack of agreement'. RESULTS: The three sections contain 24 statements with comments. Group consensus was reached in 95.8% and group agreement in 4.2%. For whole-body staging, pulmonary MDCT should be performed in all high-grade sarcomas. Whole-body MRI is preferred for staging bone metastasis, with [18F]FDG-PET/CT as an alternative modality in PET-avid tumors. Patients with alveolar soft part sarcoma, clear cell sarcoma, and angiosarcoma should be screened for brain metastases. Special algorithms are recommended for entities such as rhabdomyosarcoma, extraskeletal Ewing sarcoma, myxoid liposarcoma, and neurofibromatosis type 1 associated malignant peripheral nerve sheath tumors. Satisfaction of search should be avoided in potential multiplicity. CONCLUSION: Standardized whole-body staging includes pulmonary MDCT in all high-grade sarcomas; entity-dependent modifications and specific algorithms are recommended for sarcomas and non-malignant soft tissue tumors. CLINICAL RELEVANCE STATEMENT: These updated ESSR soft tissue tumor imaging guidelines aim to provide support in decision-making, helping to avoid common pitfalls, by providing general and entity-specific algorithms, techniques, and reporting recommendations for whole-body staging in sarcoma and non-malignant soft tissue tumors. KEY POINTS: An early, accurate, diagnosis is crucial for the prognosis of patients with soft tissue tumors. These updated guidelines provide best practice expert consensus for standardized imaging algorithms, techniques, and reporting. Standardization can improve the comparability examinations and provide databases for large data analysis.

Soft tissue tumor imaging in adults: European Society of Musculoskeletal Radiology-Guidelines 2023-overview, and primary local imaging: how and where?

OBJECTIVES: Early, accurate diagnosis is crucial for the prognosis of patients with soft tissue sarcomas. To this end, standardization of imaging algorithms, technical requirements, and reporting is therefore a prerequisite. Since the first European Society of Musculoskeletal Radiology (ESSR) consensus in 2015, technical achievements, further insights into specific entities, and the revised WHO-classification (2020) and AJCC staging system (2017) made an update necessary. The guidelines are intended to support radiologists in their decision-making and contribute to interdisciplinary tumor board discussions. MATERIALS AND METHODS: A validated Delphi method based on peer-reviewed literature was used to derive consensus among a panel of 46 specialized musculoskeletal radiologists from 12 European countries. Statements were scored online by level of agreement (0 to 10) during two iterative rounds. Either "group consensus," "group agreement," or "lack of agreement" was achieved. RESULTS: Eight sections were defined that finally contained 145 statements with comments. Overall, group consensus was reached in 95.9%, and group agreement in 4.1%. This communication contains the first part consisting of the imaging algorithm for suspected soft tissue tumors, methods for local imaging, and the role of tumor centers. CONCLUSION: Ultrasound represents the initial triage imaging modality for accessible and small tumors. MRI is the modality of choice for the characterization and local staging of most soft tissue tumors. CT is indicated in special situations. In suspicious or likely malignant tumors, a specialist tumor center should be contacted for referral or teleradiologic second opinion. This should be done before performing a biopsy, without exception. CLINICAL RELEVANCE: The updated ESSR soft tissue tumor imaging guidelines aim to provide best practice expert consensus for standardized imaging, to support radiologists in their decision-making, and to improve examination comparability both in individual patients and in future studies on individualized strategies. KEY POINTS: • Ultrasound remains the best initial triage imaging modality for accessible and small suspected soft tissue tumors. • MRI is the modality of choice for the characterization and local staging of soft tissue tumors in most cases; CT is indicated in special situations. Suspicious or likely malignant tumors should undergo biopsy. • In patients with large, indeterminate or suspicious tumors, a tumor reference center should be contacted for referral or teleradiologic second opinion; this must be done before a biopsy.

Tumor-like Lesions of Bone and Soft Tissues and Imaging Tips for Differential Diagnosis.

In the musculoskeletal system, tumor-like lesions may present similar imaging findings as bone and soft tissue tumors and can be defined as tumors on radiologic examinations. Misinterpretation of the imaging findings can lead to inappropriate clinical management of the patient.There is still some debate regarding the pathophysiology and origin of tumor-like lesions that include congenital, developmental, inflammatory, infectious, metabolic, reactive, posttraumatic, post-therapeutic changes, and some miscellaneous entities causing structural changes. Although tumor-like lesions are historically defined as non-neoplastic lesions, some of them are classified as real neoplasms.We discuss a spectrum of entities mimicking tumors of bone and soft tissues that include various non-neoplastic diseases and anatomical variants based on imaging findings.

The value of magnetic resonance arthrography in the evaluation of repaired menisci.

AIM: To evaluate the diagnostic value of direct magnetic resonance (MR) arthrography in detection of re-torn or unhealed menisci which were previously repaired. MATERIALS AND METHODS: Twenty-six menisci of 24 symptomatic patients who had undergone a meniscus repair surgery were included in this retrospective study. These patients had been evaluated with gadolinium-enhanced direct MR arthrography. A subsequent second-look arthroscopy was performed thereafter. The findings of MR arthrography were compared with the arthroscopic findings. RESULTS: Sixteen recurrent meniscal lesions were detected with MR arthrography; the remaining ten repaired menisci were evaluated as healed. At second-look arthroscopy, six out of 26 repaired menisci were evaluated as completely healed. Eight of them had incomplete healing, and 12 of them were unhealed. MR arthrography had four false-negative results, but there were none false-positive results. It was arthroscopically shown that three of these four false-negative results were belonged to patients who had incomplete healing. MR arthrography had a sensitivity, specificity, and overall accuracy of 80, 100, and 84.6 %, respectively. When incomplete lesions were left out of analysis, its sensitivity and accuracy reached to 94.8 and 94.4 %. CONCLUSION: The findings of this study showed that MR arthrography was a reliable diagnostic tool in evaluating previously repaired menisci. Yet diagnosis of incomplete meniscal lesions seemed to be challenging.

Primary tumors of the spine.

Spinal tumors consist of a large spectrum of various histologic entities. Multiple spinal lesions frequently represent known metastatic disease or lymphoproliferative disease. In solitary lesions primary neoplasms of the spine should be considered. Primary spinal tumors may arise from the spinal cord, the surrounding leptomeninges, or the extradural soft tissues and bony structures. A wide variety of benign neoplasms can involve the spine including enostosis, osteoid osteoma, osteoblastoma, aneurysmal bone cyst, giant cell tumor, and osteochondroma. Common malignant primary neoplasms are chordoma, chondrosarcoma, Ewing sarcoma or primitive neuroectodermal tumor, and osteosarcoma. Although plain radiographs may be useful to characterize some spinal lesions, magnetic resonance imaging is indispensable to determine the extension and the relationship with the spinal canal and nerve roots, and thus determine the plan of management. In this article we review the characteristic imaging features of extradural spinal lesions.

Pitfalls in MR imaging of musculoskeletal tumors.

A wide range of musculoskeletal tumors and tumor-like conditions may be encountered when patients undergo radiologic examinations. Although MR imaging is a powerful medical imaging method that has been used extensively in the evaluation of musculoskeletal tumors, nontumoral or tumorlike lesions may have similar imaging findings. The imaging features of certain normal, reactive, benign neoplastic, inflammatory, traumatic, or degenerative processes in the musculoskeletal system may mimic malignant tumors. Misinterpretation of the imaging findings can lead to inappropriate clinical management of the patient. We review and describe the MR imaging characteristics of nontumoral bone lesions that are located in the marrow cavity, cortical bone, or in both, and soft tissue lesions that may be misinterpreted as sarcoma.

Musculoskeletal brucellosis.

Brucellosis is a zoonosis of worldwide distribution caused by small gram-negative nonencapsulated coccobacilli of the genus Brucella. It is characterized by a granulomatous reaction in the reticuloendothelial system. Because it affects several organs and tissues, it may have various clinical manifestations. Musculoskeletal involvement is one of the most common locations, and the frequency of bone and joint (osteoarticular) involvement of brucellosis varies between 10% and 85%. Osteoarticular involvement includes spondylitis, sacroiliitis, osteomyelitis, peripheral arthritis, bursitis, and tenosynovitis. The most common osteoarticular finding in children is monoarticular arthritis, mostly located in the knees and hips; whereas in adults, sacroiliitis is the most frequent. Imaging studies, including radiography, computed tomography (CT), magnetic resonance (MR) imaging, and bone scintigraphy, have been used for diagnosis. Radiography is limited to evaluating the focal form of spinal brucellosis and advanced disease at the joints. CT and bone scintigraphy have limited value because of their inadequate soft tissue resolution. MR imaging is the method of choice to assess the extent of disease and follow up the treatment response. However, MR imaging has a low specificity to predict the exact cause of an osteoarticular lesion, and in case of arthralgia or symptoms of osteomyelitis or spondylodiscitis, the index of suspicion should be high in regions where the disease is endemic.

Musculoskeletal hydatid disease.

Hydatid disease is an infectious disease caused by the larval stage of the parasitic tapeworm Echinococcosis granulosus. Its distribution is worldwide. Although hydatid disease can develop in almost any part of the body, it is most commonly found in the liver and lung. Musculoskeletal involvement is rare. The radiological appearance of the hydatid disease of musculoskeletal system mimics tumors and other inflammatory conditions. Therefore preoperative diagnosis of musculoskeletal hydatid disease is sometimes difficult clinically and radiologically. On radiography, different radiographic changes may occur. In cases of osteolytic and inflammatory changes, it may mimic any variant of nonspecific or specific osteomyelitis. Bone erosion and destruction may lead to almost complete osteolysis, bone may distort, and on occasion, its radiologic appearances may be confused with those of a malignant bone tumor. Computed tomography (CT) is more accurate in delineating the area of destruction. The primary role of CT and magnetic resonance imaging is in the recognition of extraosseous spread of the hydatid disease within the soft tissues. This article reviews the pathological basis and the clinical and imaging features of musculoskeletal hydatid disease.

Intraosseous lipoma: radiological findings / Lipoma intra-ósseo: achados radiológicos

OBJECTIVE: Intraosseous lipomas may be less rare lesions than previously suggested in the literature. They have frequently been misdiagnosed as other benign bone lesions. A combination of computed tomography, magnetic resonance imaging and radiography is essential for decreasing misdiagnosis rates. MATERIALS AND METHODS: This retrospective study presents ten cases of intraosseous lipoma. The patients' ages ranged from 25 to 80 years, and six of them were female. Six patients presented with bone pain, whereas four patients were asymptomatic with incidentally discovered lesions. The involved bones were: femur (four patients), tibia (two patients), calcaneus (one patient), sacrum (one patient), iliac bone (one patient), navicular bone (one patient). All of the patients were assessed by means of conventional radiography, computed tomography and magnetic resonance imaging of the affected region. RESULTS: In all of the cases, plain films revealed well-defined lytic lesions. Both computed tomography and magnetic resonance imaging were quite useful in demonstrating fat within the femur. The histologic pattern of all tumors was that of mature adipose tissue. CONCLUSION: Intraosseous lipoma is a well-defined entity that may develop with varying presentations. Plain radiographs alone cannot establish the diagnosis of this lesion. However, both computed tomography and magnetic resonance imaging are quite useful methods in these cases.

OBJETIVO: Lipomas intra-ósseos podem ser lesões menos raras do que anteriormente sugerido na literatura. Freqüentemente têm sido erroneamente diagnosticados como outras lesões ósseas benignas. A combinação de tomografia computadorizada, ressonância magnética e radiografia é essencial para reduzir as taxas de erro diagnóstico. MATERIAIS E MÉTODOS: Este estudo retrospectivo apresenta dez casos de lipoma intra-ósseo. As idades dos pacientes variavam entre 25 e 80 anos, e seis deles eram do sexo feminino. Seis pacientes apresentavam dor óssea, enquanto quatro eram assintomáticos com lesões descobertas casualmente. Os ossos afetados foram: fêmur (quatro pacientes), tíbia (dois pacientes), calcâneo (um paciente), sacro (um paciente), osso ilíaco (um paciente), osso navicular (um paciente). Todos os pacientes foram avaliados por meio de radiografia convencional, tomografia computadorizada e ressonância magnética das regiões afetadas. RESULTADOS: Em todos os casos, as radiografias revelaram lesões líticas bem delimitadas. Tanto a tomografia computadorizada como a ressonância magnética foram bastante úteis para demonstrar gordura dentro do tumor. O padrão histológico de todos os tumores caracterizou-se por tecido adiposo maduro. CONCLUSÃO: Lipoma intra-ósseo é uma entidade bem definida que pode se desenvolver com variadas apresentações. Radiografias convencionais, isoladamente, não podem diagnosticar essas lesões. Entretanto, a tomografia computadorizada e a ressonância magnética são métodos bastante úteis nesses casos.

Solitary osteochondroma causing popliteal pseudoaneurysm that presented as a mass lesion.

Osteochondromas are the most frequently occurring bone tumors and can rarely lead to vascular complications. A 14-year-old boy with solitary exostosis of the right femur presented with a mass lesion at the posterior aspect of the thigh. Radiological studies demonstrated a popliteal artery pseudoaneurysm. In this case report, radiological findings of this lesion are reviewed.

[Imaging of articular cartilage]. / Kikirdak lezyonlarinda görüntüleme.

There have been many improvements in joint cartilage imaging in recent years with the development of new imaging methods. The purpose of cartilage imaging is to assess the integrity of the cartilage surface, the thickness and volume of the cartilage matrix and its relationship with the subchondral bone. Direct radiography, the conventional imaging method for the skeletal system, is not sufficient for assessing the joint cartilage, nor are arthrography, computed tomography, and arthrography together with computed tomography. Moreover, biomechanical changes in the joint cartilage cannot be assessed with these methods. Magnetic resonance imaging (MRI), with its superior contrast resolution and multiplanar imaging capability across tissues, has become the primary diagnostic method for assessment of joint pathologies. The morphological features of the joint cartilage can be assessed adequately with the use of MRI sequences specific to the cartilage. Appropriate use of MRI sequences to determine the type of cartilage damage, the presence and degree of accompanying pathologies in the subchondral bone will help minimize diagnostic errors. This article reviews cartilage imaging in the following aspects: the technique used in MRI for cartilage imaging, findings of cartilage pathology, and anticipation of future cartilage imaging.

The level of quality of radiology services in Turkey: a sampling analysis.

PURPOSE: To determine the quality of radiographs, which have been referred from 40 different institutions for consultation, to discuss the causes of wasted resources, and to present possible solutions. MATERIALS AND METHODS: Five experienced radiology instructors determined the types of radiological examinations referred for consultation (conventional radiography, mammography, computed tomography and magnetic resonance imaging), the institutions at which they were performed (university or state hospital, private health center), and assessed the coverage area, field of vision (FOV), and dosage of x-ray. They also investigated problems in film processing, defects in sequence-printing windows, checked window levels, and checked the amount and timing of contrast material used. According to these criteria, the reviewers subjectively classified each radiograph as: 1. Poor, examination should be completely repeated, 2. Fair, examination should be partially repeated, 3. Good, accepted as adequate, no need for an additional examination, 4. Excellent, examination was as it should be. RESULTS: We reviewed 120 radiological examinations from 40 different institutions in 4 reference centers. Frequency of problems determined for each category was as follows: coverage area 32.5% (39/120), FOV 16% (14/86), X-ray dosage 16% (15/94), film processing 31% (37/120), sequence or window 65% (53/81), window level 44% (36/81); contrast material 51% (25/49), timing of contrast material 61% (30/49). Only 22% of the examinations were classified as excellent, whereas 47% required complete or partial repetition. CONCLUSION: Approximately half of the radiological examinations in our sampling required partial or complete repetition. Health, ethical, and economic aspects of the problem necessitates the prompt application of measures to establish radiological quality control and standardization procedures.

The safety and efficacy of intraarticular hyaluronan with/without corticosteroid in knee osteoarthritis: 1-year, single-blind, randomized study.

The goal of this study was to assess the safety and efficacy of hyaluronan (HA) with/without corticosteroid in patients with knee osteoarthritis (OA). In a 1-year, randomized, single-blind trial, 24 patients were treated with HA weekly for 3 weeks, then three injections on the 6th month for a total of six injections. Sixteen patients were treated the same but with the addition of 1 ml triamcinolone acetonide prior to the first and fourth HA injection. The treatment was repeated at the sixth month. The patients were evaluated with the Western Ontario and McMaster University Osteoarthritis Index (WOMAC) and the visual analog pain scale (VAS). After 1 year, progression of OA was evaluated with magnetic resonance imaging (MRI). During the study, pain relief was marked in patients who received combined treatment with respect to WOMAC pain and VAS (p<0.05). At the first year, no progression was observed in either treatment group. Although all patients had improvement for both pain and function, HA together with corticosteroid was superior to HA alone for early pain relief. The MRI findings showed that neither treatment showed a progression on the damage of the cartilage.

[Ganglion cysts of the knee originating from tendons and ligaments]. / Diz tendon ve baglarindan köken alan gangliyon kistleri: klinik ve MRG bulgulari.

PURPOSE: To investigate the clinical features and MR imaging findings of the ganglion cysts arising from the tendons and ligaments of the knee. MATERIALS AND METHODS: One thousand six hundred and twenty knee MR examinations that had been performed in a three-year period were evaluated retrospectively for the presence of ganglion cysts originating from tendons or ligaments. Clinical findings and MRI features of the lesions were noted. RESULTS: Twenty-three patients had a ganglion cyst originating from a tendon or a ganglion, with an incidence of 1.4%. Six lesions were associated with the anterior cruciate ligament, six with the posterior cruciate ligament, six with the medial collateral ligament, two with the lateral collateral ligament, two with the transverse ligament, and one with the patellar tendon. The most common clinical finding was knee pain. There were swelling at the medial side of the knee in two patients, swelling at the lateral side of the knee in one patient and swelling in the popliteal region in one patient. CONCLUSION: MR appearance of ganglion cysts arising from the tendons and ligaments of the knee is characteristic. Meniscal cysts, pigmented villonodular synovitis, and synovial hemangioma should be considered in the differential diagnosis.

Parasitic and fungal disease of bones and joints.

Among the musculoskeletal infections, fungal and parasitic diseases are infrequent and may have a nonspecific imaging factor. The incidences of fungal and parasitic bone infections are related to geographic distribution, ethnic and nutritional factors, and occupation. Immunocompromise and ease of travel can lead to increased incidence. These are a group of chronic disorders, and delayed diagnosis is common because radiographs, computed tomography, isotope studies, and magnetic resonance imaging are useful but often do not have specific signs for determination of the causative infective fungal or parasitic organism. Definitive diagnosis is possible with a high index of clinical suspicion and aspiration.

MRI evaluation of patellar tendon defect after harvesting its central third.

PURPOSE: the purpose of this study was to evaluate defect width of patellar tendon after harvest for anterior cruciate ligament reconstruction. MATERIALS AND METHODS: we performed MRI at various time interval after graft harvest (2-96 months) on 28 patients who had had reconstruction of the anterior cruciate ligament using mid-third patellar tendon. T1 and T2 weighted axial images were obtained to assess donor site defect of the patellar tendon. Measurement of the defect width was performed at the level of menisci on the axial images. The patients were divided into two groups according to the time interval between operation and imaging. The defect width of patients with short time interval (2-12 months) was compared to the defect width of patients with long time interval (12-96 months). RESULTS: the average defect width of patients with short time interval was 6.4 mm and it was 2.2 mm for the patients with long time interval. Decreased defect width was obtained from MRI images in the patients with long time interval. Closed donor site defect was detected in 1 out of 14 patients with short time interval and 6 out of 14 patients with long time interval. DISCUSSION AND CONCLUSION: these results show that there is no complete closure of donor site defect up to 1 year. However, it seems to be nearly complete closure of patellar tendon defect in the long time period.

[Case report: MRI findings in gout]. / Gut hastaliginin MRG bulgulari.

MR imaging is not routinely used for the evaluation of tophaceous gout. However, gout may have atypical clinical and radiologic findings. It should be considered in the differential diagnosis when a mass reveals heterogeneous and low signal intensity on T2 weighted images. We present MR imaging characteristics of gout tophi and arthritis in two patients.

[Diagnostic imaging of the rotator cuff]. / Rotator manset: Görüntüleme.

The importance of imaging modalities in the evaluation of the rotator cuff has increased thanks to the development of non-invasive methods. An optimum application of the technique, appreciation of the anatomical details and imaging pitfalls, and proper interpretation of clinical findings should be incorporated in order to increase diagnostic accuracy. Ultrasonography (US) and magnetic resonance imaging (MRI) are commonly used for rotator cuff pathologies. The former has a high diagnostic accuracy in full-thickness tears, but requires operator dependency and long-term training. Both US and MRI require sophisticated equipment and present difficulties in distinguishing between partial and small full-thickness tears. In full-thickness tears, MRI may be more appropriate if imaging findings are likely to alter the course of surgical treatment. However, it is not necessary in patients in whom US may clearly show tendinosis. Magnetic resonance imaging or MR arthrography may be required in order to evaluate partial tears or suspicious small full-thickness tears in patients unresponsive to conservative therapy. A close collaboration is essential between the radiologist and the shoulder surgeon in the interpretation of clinical findings. The diagnostic accuracy will increase if the examinations are performed by a musculoskeletal radiologist.

Clear cell chondrosarcoma: unusual radiologic appearances with histologic correlation.

Clear cell chondrosarcoma is a rare variant of the bone tumors with distinct radiologic and pathologic features. In this report two cases of clear cell chondrosarcomas with atypical radiologic appearances are presented. The findings of X-ray films and MRI are described with histologic correlation. In the first case the lesion showed a very expansile and long segment involvement of the humerus. In the second case the lesion was located in the diaphysis of the femur causing a large cortical destruction.