In an autopsy study of patients with cancer, 14.6% had pathologic evidence of cerebrovascular disease (CVD), and in 7.4% clinical symptoms of CVD had been present in life. The usual risk factors for CVD were overshadowed by pathophysiologic abnormalities related to the neoplasm, including direct effects of the tumor, coagulation disorders, infections and diagnostic or therapeutic procedures. In patients with leukemia, hemorrhages (72.4%) were much more common than ischemic infarcts. In lymphoma patients, the incidence of cerebral bleeding was lower (36.3%). In both groups, the leading causes of ischemic infarction were septic thrombi and intravascular coagulation. In patients with carcinoma, cerebral infarctions (54.1%) were more frequent than hemorrhages. NBTE (18.5%) and intravascular coagulation (9.6%) were the most common etiologies. Hemorrhages other than intratumoral bleeding in patients with melanoma or germ cell tumors were unusual. The clinical presentation of CVD in patients with cancer is more often a diffuse encephalopathy, with or without localizing signs, than the typical acute onset of a focal deficit. This was particularly true with intravascular coagulation, septic infarction and subdural hematoma. Our study suggests that by knowing the clinical setting, neurologic features and laboratory findings, one can, in many instances, make an accurate clinical diagnosis that, in some cases, leads to effective treatment.