Renal metastases: clinicopathologic and radiologic correlation

The clinical and radiologic features of 27 patients with renal metastases arising from eight different types of nonlymphomatous primary malignancies are presented. Renal metastases were generally detected late in the course of the malignancy. In 23 patients there were no symptoms referable to the kidney. Urinalysis was normal in nine patients and showed microscopic hematuria in nine, gross hematuria in four, and proteinuria in four. Radiologically, metastases were usually multifocal; however, metastases arising from colon, lung, and breast carcinoma were sometimes large, solitary, and otherwise indistinguishable from primary renal cell carcinoma. Three of four melanoma metastases and three of seven lung metastases infiltrated the perinephric space. Computed tomography was the most sensitive modality, depicting renal metastases in all 24 cases in which it was employed, followed by ultrasound and intravenous urography. In patients with a history of malignancy, renal metastases outnumbered renal cell carcinomas by approximately 4:1. This study indicates that a new renal lesion in a patient with advanced, noncurable cancer is more likely metastatic than primary and that biopsy in this setting is unlikely to be of aid.     

Color and spectral Doppler mirror-image artifact of the subclavian artery

The mirror-image artifact, which has been previously described in gray-scale sonographic imaging, is also readily visualized with both spectral and color Doppler flow imaging. In 10 consecutive healthy subjects, a mirror image of the subclavian artery was readily apparent at gray-scale, spectral Doppler, and color Doppler sonography. An experimental in vitro model was constructed to demonstrate that the lung apex, which is located immediately posterior to the subclavian artery, acts as the highly reflective acoustic interface to form this artifact. Knowledge of the presence of the mirror-image artifact should be helpful to the radiologist and sonographer in avoiding misinterpretation of this important pitfall in both spectral and color Doppler flow imaging of the subclavian region, where there is a plethora of branching vessels.     

IL-1β and Interferon-γ Induce Schwann Cell Proliferation And Death

Schwann cell apoptosis (programmed cell death) has been recently observed during the development and in rare pathological conditions of the peripheral nervous system (PNS) characterized by demyelination-remyelination. However, the relevance of the phenomenon, and the characterization of the involved molecules are still controversial. This study has been designed to detect in Schwann cell tissue culture whether the administration of different doses of the two pro-inflammatory cytokines IL-1β and IFN-γ, singly or in combination, can induce Schwann cell proliferation and/or death via apoptosis. Our results indicate that the administration of IL-1β and IFN-γ induced cell proliferation and concomitant apoptosis in Schwann cells that is numerically related to the different type and dosage of the two pro-inflammatory cytokines. Moreover, Schwann cell apoptosis was maximal within 24 hours following the administration of 50 U/mL of IFN-γ, and we did not observe any synergistic action of the two pro-inflammatory molecules. These findings provide further "in vitro" evidence that cytokines can interact with Schwann cells through a mechanism that is probably mediated by the modulation in time and concentrations of these different pro-inflammatory molecules.