Radiological findings of primary retroperitoneal Ewing sarcoma

Ewing sarcomas are most commonly located in bone, while extraskeletal involvement of the retroperitoneum is extremely rare. We describe the radiologic and pathological findings in an adult patient with retroperitoneal extraskeletal Ewing sarcoma.     

Ewing sarcoma: MR imaging of chemotherapy-induced changes with histologic correlation.

In a study group of 18 consecutive patients with Ewing sarcoma proved by means of biopsy, the signal intensity characteristics of tumor on magnetic resonance (MR) images were assessed before and after chemotherapy. Sixteen patients underwent MR imaging at 1.5 T before chemotherapy; all 18 patients underwent MR imaging at 1.5 T within 10 days after chemotherapy. Standard spin-echo sequences were used with T1 and T2 weighting in all patients. The primary tumor was visualized in all 16 patients who underwent MR imaging before chemotherapy. Histologic correlation, obtained in 14 patients, showed that areas of high T2-weighted signal intensity on MR images obtained after chemotherapy may represent tumor necrosis, cystic hemorrhagic areas, and fibroblastic repair tissue. In 10 patients (71%), microscopic clusters of viable tumor cells were depicted in areas of both low and high signal intensity after treatment. It is concluded that MR imaging is unreliable for exclusion of active disease, although a pattern of change in signal intensity is qualitative evidence of chemotherapeutic effect.     

Central nervous system extraosseous Ewing sarcoma: radiologic manifestations of this newly defined pathologic entity

Although these entities are histologically similar, recent advances in molecular genetics have allowed the distinction of central nervous system extraosseous Ewing sarcoma (CNS-EES) from central primitive neuroectodermal tumors (c-PNET) including medulloblastoma and supratentorial PNET. We present 2 cases of pathologically confirmed CNS-EES. Knowledge of CNS-EES as a distinct entity enables the neuroradiologist to suggest the proper diagnosis and the need for special immuno-histochemical and molecular studies to confirm the diagnosis. Because treatment and prognosis are vastly different, the proper diagnosis of CNS-EES versus c-PNET is critical.     

Imaging of primary Ewing sarcoma with 13N-L-glutamate

Eleven patients with untreated primary Ewing sarcoma were studied with intravenously administered 13N-labeled L-glutamate. Seven were repeatedly scanned during chemotherapy using this agent and 99mTc-methylene diphosphonate (99mTc-MDP). The untreated primary tumor was distinctly visualized with 13N-L-glutamate in all cases; the distribution of 13N label in the tumor sometimes differed from that of 99mTc. A kinetic study showed rapid uptake of 13N by tumor tissue. Repeat scans following therapy indicated that 13N-L-glutamate and 99mTc-MDP uptake showed changes consistent with histological findings following subsequent surgery. 13N uptake often decreased more markedly than 99mTc uptake during chemotherapy, but metastatic lesions were not visualized with 13N-L-glutamate. Tumor imaging with this labeled amino acid may be of value in assessing the response of primary Ewing sarcoma to chemotherapy.     

Radiology-pathology conference: primary perinephric and renal extraosseous Ewing's sarcoma

Ewing's sarcoma/primitive neuroectodermal tumor is a rare entity belonging to a family of neoplasms of neuroectodermal origin. These highly aggressive neoplasms overwhelmingly affect children and young adults. A quarter of Ewing's sarcomas occur principally in the soft tissues with primary involvement of the perinephric fat and kidney being exceptionally rare. We present a 38-year-old man with primary Ewing's sarcoma of the perinephric fat and kidney diagnosed 2 years earlier who subsequently developed an infiltrating left renal and perinephric mass.     

Spinal epidural extraskeletal Ewing sarcoma: MR findings in two cases

SUMMARY: We report the CT myelography and MR findings of two cases of extraskeletal Ewing sarcoma involving the spinal epidural and paravertebral spaces in a middle-aged man (case 1) and a young woman (case 2). In both cases CT myelography showed epidural and paravertebral masses on one side, with widening of the ipsilateral neural foramina at the C5-C6 level in case 1 and at the C7-T1 level in case 2. On MR images, the masses were isointense to muscle on T1-weighted images, hyperintense on T2-weighted images, and showed moderate enhancement on contrast-enhanced T1-weighted images. In one case, all pulse sequences showed linear signal voids, representing the vertebral artery encasement within the mass. The intradural component connected with the main mass was detected in the other case.     

Use of MR imaging to assess results of chemotherapy for Ewing sarcoma

MR imaging was used to monitor the results of initial chemotherapy of primary Ewing sarcoma of bone. The signal intensities of the soft-tissue and marrow components of the tumor were evaluated on T2-weighted images obtained in 10 patients (nine with responsive tumors) at presentation and during and immediately after completion of two cycles of chemotherapy. MR evidence of marrow and soft-tissue involvement was seen in all tumors at presentation. After treatment, the bone-marrow component of the nine drug-sensitive tumors showed an increase in signal intensity that in eight cases became comparable to that of water. Changes in signal intensity of the soft-tissue component were variable, consisting of increases in two of the responsive lesions, no change in three, a decrease in two, and complete resolution of the soft-tissue mass in two. There was no increase in signal intensity of either the bone-marrow or the soft-tissue component of the single nonresponsive tumor. All of the responsive tumors showed advanced healing, and abundant bony sclerosis was apparent on CT. Bone-marrow examinations, performed in seven of the nine patients with responsive lesions, disclosed no evidence of tumor in four. Two patients had residual extramedullary tumor; the nonresponsive lesion contained sheets of tumor cells. The increase in marrow signal intensity on T2-weighted images was associated with replacement of marrow elements by a loose, hypocellular myxoid matrix containing modest amounts of collagen, consistent with response to chemotherapy and eradication of disease. Therefore, an increase in the T2-weighted signal intensity of the bone-marrow component of Ewing sarcoma of bone reflected a favorable response to chemotherapy. MR signal changes, however, were not predictive of resolution of malignant disease within adjacent soft tissue.     

骨外尤文肉瘤的超声诊断价值

目的探索骨外尤文肉瘤的声像图特点。方法回顾性分析3例经病理证实的骨外尤文肉瘤的声像图表现。结果3例骨外尤文肉瘤均呈实性,呈低或极低回声,内部回声紊乱,分布不均,彩色多普勒超声检查显示内部血流丰富,呈低速低阻动脉血流。结论超声检查可清晰显示骨外尤文肉瘤的声像图改变,结合临床病史,可以提供提示性诊断信息,但缺乏特异性表现,尚需与其他软组织肿瘤相鉴别。     

Primary extraosseous pulmonary osteogenic sarcoma: CT findings.

This is a report of a primary extraosseous osteogenic sarcoma of the lung. The patient presented with fever and productive cough. Chest radiography and CT showed a cavitary lesion with an air-fluid level. The lesion was treated as an abscess. Despite aggressive antibiotic therapy and drainage, the patient continued to deteriorate rapidly. At autopsy the lesion was found to be a primary extraosseous pulmonary osteogenic sarcoma.     

子宫内膜少见原发性肉瘤的MR表现

目的探讨子宫内膜少见原发性肉瘤的MR表现及特征,并与病理学对照,以提高对该类疾病的诊断及鉴别诊断能力。方法回顾性分析经手术病理证实的6例子宫内膜少见原发恶性肿瘤的MR表现并复习相关文献。结果子宫腺肉瘤2例,平扫T1WI呈等低信号T2WI呈不均匀高信号影,结合带连续性中断,伴肌层受侵,肿块内信号不均匀可见囊变坏死。子宫癌肉瘤3例,表现为T1WI呈等低混杂信号,T2WI呈不均匀高信号影,增强后呈不规则明显强化,其中1例合并盆腔及腹膜种植转移,1例合并大量盆腔积液。子宫间质肉瘤1例,表现为宫腔内巨大软组织肿块,T1WI等、低信号,T2WI呈高信号,伴出血及坏死表现为不均匀高信号影,增强扫描后实质部分呈不规则明显强化。结论 MRI平扫及动态增强扫描并结合临床资料可以提高子宫内膜少见原发性肉瘤的诊断,但确诊仍需依靠病理学检查。     

Primary Ewing sarcoma of rib

Ewing sarcoma is a relatively common, highly malignant bone tumor that typically occurs in adolescents and young adults aged 10-25 years. Our archives contain 328 cases of histologically proved and radiologically correlated Ewing sarcoma collected in consultation over 40 years. From this series, we identified 34 lesions (10%) arising in ribs. Radiographically, the affected rib was predominantly lytic in most (82%) cases, but mixed lytic-sclerotic (9%) and even predominantly sclerotic (9%) patterns were also encountered. The affected rib was "expanded" in 35% of cases, although the contour change was usually mild. Abnormalities of the affected ipsilateral hemithorax varied from subtle, isolated rib involvement to solitary rib involvement accompanied by complete opacification of the hemithorax. We describe the spectrum of radiologic findings of primary Ewing sarcoma of rib, augmented where appropriate by accompanying pathologic material.     

Limited remodelling of expansile Ewing sarcoma after treatment.

Radiological findings of Ewing sarcoma have been well documented, and bone expansion or cystic change is known to be a relatively uncommon finding. On the other hand, expected changes in Ewing sarcoma after treatment have also been reported, e.g. regression of extraosseous soft tissue mass, regression and organization of the periosteal reaction, and remodelling of the lytic or sclerotic bone changes. However, remodelling of bone is often limited or incomplete. We saw an atypical change in Ewing sarcoma after treatment due to lack of significant remodelling of the expanding bone. Because such changes might be a cause of misdiagnosis, knowledge of it will help the radiologist in the follow up evaluation.     

Ewing sarcoma of the skull with an unusual pattern of reactive sclerosis: MR characteristics

A case of primary Ewing sarcoma involving the occipital bone with an unusual radiographic feature--markedly thickened bone--is described. Magnetic resonance imaging was more helpful than CT in determining the lesion extent due to lack of bone artifact and since it showed the precise relationship of the neoplasm to the tentorium on direct coronal imaging.     

Radiological features of extraskeletal Ewing sarcoma

The radiological features of extraskeletal Ewing sarcoma were reviewed in 22 patients whose average age was 22 years. Tumours were located in the extremities (11 patients), abdomen or pelvis (six patients) and the chest (five patients). The tumours ranged in size from 2 cm to 20 cm, were mainly well circumscribed and showed no evidence of calcification prior to treatment. Most tumours (13 out of 14) were of low attenuation or contained areas of lower attenuation than muscle on computed tomographic examination, and in six out of seven patients studied by ultrasound the tumours were hypoechoic or partly anechoic. No distinctive post-contrast medium enhancement pattern on CT examination (11 patients) or angiographic features (three patients) were evident. Tumour haemorrhage was a frequent microscopic finding and changes consistent with this were present in one patient on magnetic resonance imaging examination. Distant metastases or local recurrence developed in 13 patients with lung being the most frequent metastatic site (eight patients). Although its radiological features are non-specific, extraskeletal Ewing sarcoma should be included in the differential diagnosis of noncalcified soft-tissue tumours especially in a young age group and where located in an extremity or paravertebral region of the chest.     

Spinal Ewing sarcoma: Misleading appearances

The plain radiographic and computed tomographic (CT) findings in two unusual cases of spinal Ewing sarcoma are reported. Radiographic features resembling neuroblastoma in one case and aneurysmal bone cyst in the other were present. These findings may be misleading and distinguishing characteristics in each case are discussed.     

MR imaging of synovial sarcoma.

The MR imaging findings in 12 cases of synovial sarcoma are illustrated. The MR appearance most indicative of the tumor is an inhomogeneous septated mass with infiltrative margins located close to a joint, a tendon, or bursae, especially if soft-tissue calcification can be seen on CT scans or plain radiographs.     

Ewing’s sarcoma of the thumb

 The case of a 51-year-old man with Ewing’s sarcoma of the thumb is presented. The tumor involved the distal phalanx of the right thumb, associated with an impressive extraskeletal mass. Histology revealed a round cell sarcoma with a positive immunoreactivity with monoclonal antibody O13. Five years after disarticulation at the metacarpophalangeal joint, the patient is alive without recurrence or metastasis.     

肾尤文肉瘤一例

患者男,26岁.右侧腰背部间隙性胀痛2周,于2009年11月10日入我院就诊.B超示右肾实质性占位性病变. CT检查:平扫右肾于肾门上方体积增大,见混杂密度影,高密度血块CT值68 HU,等密度肿瘤实质CT值35 HU,肾包膜下见半月形低密度影,未凝固的血液CT值14 HU.