Magnetic resonance imaging of musculoskeletal soft tissue masses

The role of MR imaging in the evaluation of children with large, deep, or infiltrative soft tissue masses is to characterize and determine the extent of the lesion for treatment planning. There are a small number of soft tissue tumors with MR imaging appearances characteristic enough to allow a specific diagnosis, obviating biopsy. In the remaining cases with nonspecific imaging appearances, MR imaging is used for anatomic staging, but tissue sampling is still required for determining histology and grading.     

软组织滑膜肉瘤的CT和MRI诊断

目的：探讨软组织滑膜肉瘤的影像学表现。方法：回顾性分析17例经手术病理证实的软组织滑膜肉瘤患者的临床及影像学资料,分析其影像学征象。结果：大部分滑膜肉瘤影像表现为邻近关节边界较为清楚的团块状或分叶状软组织肿块,肿瘤体积一般较大（〉5 cm,88%）。CT平扫可见肿瘤大部分密度与肌肉密度相似,其内可见范围不等的低密度区,1例见团块状钙化,2例见斑点状钙化,主要位于肿块的周边。较大的肿瘤（〉5 cm）在MR T1WI上与肌肉信号相比呈不均匀等信号或稍高信号,在T2WI上表现为以高信号或稍高信号为主的混杂信号,5例肿块内可见低信号分隔;较小的肿瘤（〈5 cm）在各序列上均表现出信号的均匀性;增强扫描大部分肿瘤呈明显不均匀强化。结论：软组织滑膜肉瘤的影像学表现具有一定的特征性,CT和MRI综合评价有助于提高滑膜肉瘤的诊断准确性。     

Magnetic resonance imaging of musculoskeletal tumors: skeletal and soft tissue masses

The purpose of this article is to review the MRI characteristics of musculoskeletal tumors, including skeletal and soft tissue masses. MRI has become the premier imaging modality for the evaluation of musculoskeletal tumors because of its excellent soft tissue contrast, its sensitivity to bone marrow and soft tissue edema, and its multiple imaging planes. In a substantial subset of cases, MRI can provide a diagnosis or a short differential diagnosis, while certain tumors have no distinguishing signal characteristics. MRI of musculoskeletal tumors can also be challenging, because the MRI appearance of certain lesions can be misleading, and a knowledge of the instances in which MRI over- and underestimates the malignancy of lesions is invaluable. The importance of correct protocols for tumor evaluation, both in diagnosis and in pre-operative evaluation, are discussed. Common pitfalls that may over- or underestimate the aggresivity of lesions will be highlighted, as will the role of gadolinium enhancement in the evaluation of lesions. The MRI appearance of common benign and malignant muculoskeletal lesions will be illustrated.     

Challenges to implementation of the new Coroners' (Amendment) Rules 2005: experience from a tertiary paediatric pathology centre

In the UK sudden unexpected childhood deaths are referred to Her Majesty's Coroner (HMC) for postmortem examination during which small tissue samples are obtained for diagnostic purposes. Recent changes to regulate tissue use include the Coroners' (Amendment) Rules 2005. We audited the impact of these at a specialist paediatric centre. A retrospective audit of HMC tissue forms for autopsies was performed between 1 June 2005 - 31 May 2006, with regard to the options provided to, and chosen by, parents. Of 213 coronial autopsies, 178 were non-forensic. Tissue forms were submitted pre-autopsy in 25 (14%). An additional 47 were received after sending follow-up letters for a total of 72/178 (40%). Forms varied between coroners, but most failed to distinguish between blocks, slides, and other tissue samples and 6/40 (15%) forms did not specifically allow an option for research consent. Forty-three (60%) parents opted for retention, with 34 (79%) also consenting to research. Only six (8%) requested return of tissue. A simple, unified tissue disposal form and information sheet for all HMC districts, which includes appropriate options, would ensure that parents' wishes are met, to achieve best practice, maximise sample availability for positive societal outcomes such as teaching and research, and to comply with new regulations.     

Radiologic manifestations of proximal-type epithelioid sarcoma of the soft tissues

OBJECTIVE: This study describes the MR imaging findings of focal osteochondral lesions found in the hips of 11 athletes with persistent pain and normal findings on radiographs. CONCLUSION: Osteochondral lesions of the femoral head are seen on MR imaging as focal, medial areas of high T2-weighted and low T1-weighted signals and should be considered as a possible cause of persistent hip or groin pain in young, high-level athletes because the institution of appropriate treatment may help to prevent late degenerative sequelae.     

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

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

Reinterpretation of radiological imaging in patients referred to a tertiary referral centre with a suspected pancreatic or hepatobiliary malignancy: impact on treatment strategy

Our objective was to determine the clinical importance of reinterpretation of radiological investigations performed in a referring hospital and the value of additional investigations in a referral centre. A panel of four experts retrospectively evaluated the technical quality of radiological investigations and made reinterpretation reports, of 78 patients referred with a suspected pancreatic or hepatobiliary malignancy. The value of additional radiological investigations performed in the referral centre was assessed. The quality of ultrasound and CT examinations was sufficient for reinterpretation in (36 of 69) 52% and (42 of 60) 70%, respectively. The reinterpretation reports of the ultrasound investigations were scored as "in accordance" in (30 of 36) 83%, as "minor discordance" in (3 of 36) 8% and as "major discordance" in (3 of 36) 8%. For CT proportions of (29 of 42) 69%, (8 of 42) 19% and (5 of 42) 12%, respectively, were found. Additional ultrasound (n=55) showed no additional findings in 16%, minor additional findings in 53% and major additional findings in 31% of cases. For additional spiral CT scan (n=47) results were of 21, 47 and, 32%, respectively. Reinterpretation of ultrasound and CT resulted in a change in treatment strategy for 7 patients (9%). Additional ultrasound or CT resulted in a change in treatment strategy for 24 patients (30%). Improved communication and reinterpretation of radiological investigations may reduce unnecessary referral. Electronic Publication     

Ewing's sarcoma of the soft tissues: apropos of 3 cases and review of the literature]

Three cases of extraosseous Ewing sarcoma are reported. This pathology of the young adult is very rare as shown by the review of the literature. Clinical or imaging (CT or MRI) findings are non-specific and diagnosis is based on histology. Nonetheless, this diagnosis should be considered in all patients with primary soft tissue tumors.     

The diagnosis of pulmonary metastases on chest computed tomography in primary bone sarcoma and musculoskeletal soft tissue sarcoma

The lungs are the commonest site of metastasis for primary high-grade bone and soft tissue sarcoma, but current guidelines on the management of pulmonary nodules do not specifically cater for this group of patients. The current article reviews the literature from the past 20 years that has reported the CT features of pulmonary metastases in the setting of known primary bone and soft tissue sarcoma, with emphasis on osteosarcoma, chondrosarcoma, and trunk and extremity soft tissue sarcoma, the aim being to aid radiologists who report chest CT of musculoskeletal sarcoma patients in deciding which lesions should be considered metastatic, which lesions are indeterminate and require follow-up, and which lesions are of no concern.     

A review of staging chest CT in trunk and extremity soft tissue sarcoma

Objectives:To determine the incidence of pulmonary metastases on chest CT in trunk and extremity soft tissue sarcoma based on two size criteria, and to identify factors associated with metastases.Methods:Retrospective review of chest CT studies in patients with trunk and extremity soft tissue sarcoma over an 18-month period. Data collected included patient age/sex, tumour location, size and relationship to fascia. All chest CTs were reviewed for the presence of metastases which were diagnosed according to two size criteria: multiple nodules > 5 mm in size or multiple nodules > 10 mm in size. Follow-up CT studies were reviewed in cases initially considered indeterminate.Results:127 males and 73 females were included (mean age 57.1 years; range 10–90 years). 147 (73.5%) tumours were deep to the fascia and 53 (26.5%) superficial. Tumour size classified according to the 12 AJCC 2019 criteria was: T1 = 52, T2 = 76, T3 = 39, T4 = 33. Based on nodule size >5 mm, 73 (36.5%) patients had no metastases, 42 (21%) had metastases, while 85 (42.5%) studies were indeterminate. Based on nodule size >10 mm, 73 (36.5%) patients had no metastases, 28 (14%) had metastases, while 99 (49.5%) studies were indeterminate. Larger maximum dimension of the primary tumour was a risk factor for pulmonary metastases using both size criteria.Conclusion:The incidence of pulmonary metastases at presentation in trunk and extremity soft tissue sarcoma is 14–21%. 42.5–49.5% of chest CTs were indeterminate.Advances in knowledge:The incidence of pulmonary metastases at presentation in trunk and extremity soft tissue sarcoma is 14–21%. Indeterminate pulmonary nodules are also very common.     

Synovial sarcoma of the soft tissues: prognostic significance of imaging features

OBJECTIVE: This study assessed the prognostic value of computed tomography (CT) and magnetic resonance (MR) imaging features in synovial sarcoma of the soft tissues. METHODS: CT and MR imaging studies were performed in 30 patients with pathologically confirmed synovial sarcoma of the soft tissues. CT and MR imaging findings obtained by 2 radiologists with agreement by consensus were compared for histopathologic features including tumor grade. Univariate analyses were conducted to clarify the impact of imaging findings on overall survival with a medium duration of 32 months. Multivariate analysis was estimated using a Cox proportional hazards model with the relative risk of each variable. RESULTS: Statistically significant imaging findings favoring a diagnosis of high-grade tumor included proximal distribution (P < 0.01), large tumor size (>10 cm, P < 0.05), the absence of calcification (P < 0.05), tumor possessing cyst (P < 0.01), the presence of hemorrhage (P < 0.05), and the presence of triple signal pattern (P < 0.05). Univariate analysis showed that proximal distribution (P < 0.05), tumor size larger than 5 cm (P < 0.01), the absence of calcification (P < 0.01), the presence of hemorrhage (P < 0.05), and the presence of triple signal pattern (P < 0.05) had a significant association with the disease-free survival (DFS). Multiple logistic regression models revealed that tumor size larger than 10 cm had a significant impact on the DFS with relative risk of 18.8 (P < 0.05). CONCLUSION: CT and MR imaging studies allow prognosis prediction in patients with synovial sarcoma of the soft tissues.     

Primary alveolar soft part sarcoma of vertebra: a case report and literature review

Alveolar soft part sarcoma (ASPS) is a rare malignant soft tissue tumor, which rarely occurs in bone. We present a case of ASPS in a 23-year-old man with a 2-month history of back pain. Computed tomography scanning and magnetic resonance images demonstrated a destructive process in the 12th thoracic vertebra associated with a unilateral soft tissue mass. The tumor showed evidence of hypervascularity on MRI; it obviously was enhanced on T1-weighted images after injection of Gd-GDPA, and signal voids were shown on all pulse sequences which may help to differentiate ASPS from other tumors of the vertebra. We believe that this is the first case of ASPS arising in a vertebra.     

成人腰部软组织透明细胞肉瘤1例

透明细胞肉瘤(clear cell sarcoma,CCS)又称为软组织恶性黑色素瘤(malignant melanoma of soft parts,MMSP),是一种发病率较低的恶性软组织肉瘤,约占软组织肉瘤的1％.现报道1例如下.     

The differential diagnosis of trunk and extremity dermal and sub-dermal lesions referred to a musculoskeletal oncology service

ObjectivesTo determine the differential diagnosis of dermal and sub-dermal soft tissue masses which do not extend to the deep fascia that are referred to a specialist musculoskeletal oncology service.Materials and methodsReview of all patients referred to a specialist musculoskeletal oncology service over a 13-month period with a dermal or sub-dermal soft tissue mass which did not extend to the deep fascia based on MRI appearances. Data collected included age, gender, site and maximal lesion size, and final histological diagnosis for biopsied and/or excised lesions.Results56 patients were included, 21 (37.5%) males and 35 (62.5%) females with mean age 49.75 years (range 5–86 years). 3 patients had 2 lesions making a total of 59 lesions, 11 (18.6%) dermal and 48 (81.4%) sub-dermal. Histological diagnosis was available in 44 (74.6%) cases, of which 11 (25%) were non-neoplastic, 23 (52.3%) were benign neoplasms, and 10 (22.7%) were malignant neoplasms. Although older age at presentation and greater mean maximal tumour dimension were seen with malignant lesions, these did not reach statistical significance (p = 0.154 and 0.102 respectively). There was also no relationship between skin involvement from sub-dermal lesions and malignancy, but 5 of 6 dermal lesions which showed an exophytic growth pattern were malignant.ConclusionsThe differential diagnosis of dermal and sub-dermal lesions which do not reach the deep fascia is wide with a malignant lesion being the cause in almost one-quarter of cases.