3D representations of the observed distributions of brain metastases according to primary origin. Stereotactic volumetric Cartesian coordinates obtained from the Leksell surgical coordinate frame in the x, y, and z planes at the time of GKRS treatment were recorded for each individual metastatic lesion (breast [285 lesions], colon [52], lung [502], melanoma [1099], and renal cell carcinoma [168]). Figure is available in color online only.