PREDILECTION OF BRAIN METASTASIS IN GRAY AND WHITE-MATTER JUNCTION AND VASCULAR BORDER ZONES

BACKGROUND, The purpose of this study was to assess the importance of the vascular border zone and the gray and white matter junction in the distribution of brain metastases. METHODS, We reviewed the medical re cords, computed tomography (CT) or magnetic resonance imaging (MRI) of 105 patients with secondary brain tumors. The metastatic lesions note d on CT scans or MRI were marched with a predetermined standard sheet containing axial images with shading on the border zones. To be includ ed in the border zones, the center or more than 50% of the lesion had to be situated within these zones. RESULTS. Among 100 evaluable patien ts, there were 302 metastatic brain lesions. Of the 302 lesions, 210 l esions were 2 cm or smaller in greatest dimension and located in cereb ral and cerebellar hemispheres. The major vascular border zones were t he site of predilection for 103 lesions (62%) although the border zone s constitute only 29% of the area. Gray and white matter junction was the preferred site for 135 lesions (64%). CONCLUSIONS. The results dem onstrated that brain metastasis occurs in the vascular border zone reg ions and the gray and white matter junction more frequently than previ ously recognized, and also supported the notion that metastatic emboli tend to lodge in an area of sudden reduction of vascular caliber (gra y/white matter junction) and in the area most distal vascular field (b order zone). (C) 1996 American Cancer Society.