Brain abscess mimicking brain tumor.

We review our experience with brain abscesses presenting as primary brain tumor over a 5-year period (1983 to 1988). Four of 66 (6%) patients admitted with the diagnosis of primary brain tumor by computed tomographic scans were found at craniotomy to have brain abscesses. Periapical abscesses found after surgery were determined to be the cause of brain abscess in two of four patients. Our experience suggests that periapical abscess may be a more frequent cause of brain abscess than previously thought, and should be considered before surgery in patients with a suspected brain tumor.