Clinical occurrence of subclavian venous thrombosis due to indwelling catheters is rare, but there is some evidence that subclinical thrombosis frequently occurs. It is purpose of this study to report the results of a prospective investigation in patients with subclavian vein catheters. Fifty-two patients admitted to the Istituto Nazionale Tumori of Milan and candidate to infraclavicular percutaneous catheterization of the subclavian vein were evaluated. There were 26 polyvinyl chloride and 26 rubber silicone catheters, which were correctly positioned in the superior vena cava-atrium. Average duration of the intravenous stay was 12.8 days. Asymptomatic thrombosis was venographically demonstrated in 46.1% of the polyvinyl chloride catheters and in 11.5% of the silicone ones (p = 0.005). The average age of catheters with or without thrombosis was 10.8 and 13.8 days, respectively. Addition of heparin to the infusate (1 U/ml) did not reduce the thrombosis rate in polyvinyl chloride or in silicone catheters, but risk of thrombosis was significantly higher (p = 0.03) in polyvinyl chloride catheters without heparin in comparison to the silicone ones. Osmolarity of the infusional fluid, manipulation during the cannulation, colonization of the catheter tip, and duration of the intravenous stay of the catheter apparently did not influence the rate of thrombosis. Since the natural history of the thrombotic subclavian veins is not known, some caution must be paid to repeat the percutaneous cannulation of the same vein and the change the catheter over a guidewire.

Evaluation of the response to treatment by means of conventional imaging and clinical examination can be particularly difficult because of the fibrosis induced by cytotoxic drugs or the small volume of residual disease. The additional information supplied by MRI could therefore allow a more conservative surgical approach in selected cases of optimal response to treatment, as well as a much more accurate follow-up. Furthermore, the variation in dynamic parameters according to the vitality of residual disease could in the future become a useful tool for monitoring the effectiveness of anti-angiogenetic drugs.

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Background. A residual mediastinal mass after treatment represents a common diagnostic problem in the management of patients with Hodgkin lymphoma (HD). Conventional diagnostic radiology, computed tomography (CT), or ultrasonography (US) do not adequately reflect changes as fibrosis or necrosis. Gallium‐67 (67Ga) imaging has been proven to be useful for the evaluation of HD in the mediastinum. The authors compared the ability of gallium scan and magnetic resonance imaging (MRI) to evaluate the mediastinal disease in the follow‐up of patients with HD. Methods. Thirty‐four patients previously treated for HD were investigated with gallium scan, MRI, and all the other investigations to evaluate the mediastinal region. Sixteen patients were in restaging after treatment, and 18 were investigated for suspected radiologic recurrence in the mediastinum (follow‐up, 9–75 months). The results of gallium scan and MRI were matched with clinical findings during the follow‐up. Results. A sensitivity of 85.7% for 67Ga and 92.8% for MRI was found, while the specificity was 100% for the scan and 80.6% for MRI. The predictive positive value that resulted was 100% for 67Ga and 68.4% for MRI. Conclusions. Both examinations were accurate in assessing the activity of residual masses in the mediastinum after treatment. 67Ga showed a lower sensitivity in comparison with MRI, but 67Ga frequently overestimates the presence of pathologic tissue. The authors acknowledge the complementary role of these two tests, but if only one of these examinations can be performed for logistic or economic reasons, then gallium scan represents the single most adequate diagnostic procedure.