James G. Lorigan

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.

MR imaging of malignant pleural mesothelioma.

The magnetic resonance (MR) findings in three patients with malignant pleural mesothelioma are described. All patients had a circumferential pleural mass surrounding the lung on the affected side. These tumors had a signal of intermediate intensity on T1-weighted images. The T2-weighted images showed a slight increase in signal intensity of the mass, with focal areas of very high signal intensity due to pleural fluid. Adenopathy was demonstrated by CT and MR in two patients. The extent of the tumor and its effects on adjacent structures were well appreciated on the coronal MR images.

Detection of hepatic metastases in breast cancer: the role of nonenhanced and enhanced CT scanning.

Nonenhanced and enhanced CT was compared in 88 patients with breast cancer and hepatic metastasis. Twenty-five patients had bolus, sequential dynamic CT, and 63 patients were scanned more slowly after a bolus or during drip infusion. Metastatic lesions were more conspicuous on nonenhanced CT and became isodense or nearly isodense after contrast medium administration in 28% of the patients scanned dynamically and in 29% of those scanned more slowly. Although breast cancer has not generally been considered a common origin of hypervascular metastases, we recommend that it be treated as such and that both enhanced and nonenhanced CT of the liver be obtained when patients are screened for metastasis.

Synovial sarcoma: MR imaging

Ten patients with biopsy-proved synovial sarcoma were evaluated by magnetic resonance (MR) imaging on a 1.5-T unit. The lesions showed intermediate signal intensity on T1-weighted images and heterogeneous high signal intensity on T2-weighted images. Tumors were well-demarcated from normal tissues. Additional information included adjacent bone involvement (one case), femoral vein invasion by tumor (one case), and hemorrhage within the tumors (one case). Four patients underwent a repeat MR examination following chemotherapy. This showed a decrease in size and increase in the signal intensity of three tumors on T2-weighted images, proven to be due to necrosis in one. These changes correlated with clinical regression of disease. While MR in synovial sarcoma does not have any specific signal intensity, it proved to be useful in defining the extent of disease and in determining the response to chemotherapy.

CT and MR imaging of malignant germ cell tumor of the undescended testis

Preoperative localization of the impalpable undescended testis is necessary to facilitate proper surgical planning. There is an increased incidence of malignant change in the undescended testis; demonstration of malignancy before surgery will significantly alter the treatment. We describe the computed tomographic (CT) and magnetic resonance (MR) findings in 2 patients with malignant change in an intraabdominal testis. The CT scan revealed lesions with areas of low density, 1 of which had focal calcifications; MR revealed lesions of predominantly low or intermediate signal intensity on both long and short TR/TE images, with some areas of very high signal on both sequences. After initial management with chemotherapy, the residual tumor was surgically resected. In neither instance was residual normal testis demonstrated.Both CT and MR are ideal methods of examining malignant transformation of the undescended testis, because of their ability to characterize the internal structure of the organ and, in the case of MR, its capacity for multiplanar imaging. They are almost of equal value except for the ability of CT to identify calcification and of MR to diagnose hemorrhage.

Results of radical nephrectomy for peripheral well-circumscribed renal cell carcinoma

Recently, several authorities have argued that, whenever surgically feasible, parenchyma-conserving surgery rather than radical nephrectomy should be the preferred treatment for renal cell carcinoma. They affirm that the results reported following partial nephrectomy are as good as those reported following radical nephrectomy for renal cell carcinoma. However, parenchyma-conserving surgery is usually performed only for relatively small, well-circumscribed tumors that do not involve the collecting system extensively or the renal hilum. To determine the results when radical nephrectomy is used to manage similar tumors, we reviewed the clinical records and arteriograms of 111 patients with renal cell carcinoma. Review of the arteriograms showed that parenchyma-conserving surgery could have been performed in 10 cases (9%). The disease-free survival rate for these 10 patients after radical nephrectomy was 100 percent, and they had no local recurrences. On the basis of these data, we believe that radical nephrectomy remains the best treatment for all patients who have renal cell carcinoma and a normal contralateral kidney.

Macroglobulinaemic lymphoma presenting with perirenal masses

Perirenal masses are an uncommon manifestation of lymphoma. They are almost always associated with lymphoma elsewhere and usually represent direct spread from retroperitoneal lymph nodes (Jafri et al, 1982; Heiken et al, 1986). Renal or perirenal lymphoma may present as an abdominal mass, hydronephrosis, impairment of renal function, or as an incidental finding (Jafri et al, 1982; Horii et al, 1983; Heiken et al, 1986). We describe an unusual case of macroglobulinaemic lymphoma in a patient who presented with perirenal masses, correlating the findings on ultrasound, computed tomography (CT) and magnetic resonance (MR).

Open-quiz solution: Case report 578

This 18-year-old w o m a n was referred for eva lua t ion o f a painful , en la rg ing mass on the inner aspect o f her left uppe r an~ . On examina t ion , a 5 x 7 cm mobi le mass on the media l aspect o f the left u p p e r a r m was no t ed to extend into the axilla. P la in r a d i o g r a p h s showed a lucent defect in the head o f the humer us (Fig. I) . M a g n e t i c r esonance ( M R ) imag ing was p e r f o r m e d in the co rona l and axial p lanes on a Signa (Genera l Electric, Mi lwaukee ) 1.5-T unit , using a surface coil. A 3 x 3 x 8 cm mass was demons t r a t ed , ex tending d is ta l ly f rom the co raco id process , be tween the heads o f the biceps muscle in to the an te r io r aspect o f the u p p e r arm. O n T l w e i g h t e d images, the s ignal in tens i ty o f the mass was sl ightly h igher than tha t o f su r round ing muscle wi th an a rea o f very high signal infer ior ly (Fig. 2A) . On T2-weighted images, a h igh signal t h r o u g h o u t the lesion was presen t with the distal p o r t i o n again sl ightly br igh te r (Fig. 2 B). N o areas o f s ignal d r o p o u t were ident i f ied. The mass was resected.

Case report 578

Address reprint requests to: Herman I. Libshitz, M.D., Department of Diagnostic Radiology, The University of Texas M.D. Anderson Cancer Center, 1515 Holcombe Blvd., Houston, TX 77030, USA performed in the coronal and axial planes on a Signa (General Electric, Milwaukee) 1.5-T unit, using a surface coil. A 3 x 3 x 8 cm mass was demonstrated, extending distally from the coracoid process, between the heads of the biceps muscle into the anterior aspect of the upper arm. On T1 weighted images, the signal intensity of the mass was slightly higher than that of surrounding muscle with an area of very high signal inferiorly (Fig. 2A). On T2-weighted images, a high signal throughout the lesion was present with the distal port ion again slightly brighter (Fig. 2B). No areas of signal dropout were identified. The mass was resected.