Neoplasms appear to be rather rare in the raccoon (Procyon lotor). In a retrospective survey of over 400 raccoon necropsies, only an astocytoma of the brain and a fibroma of the skin were observed. 3 However, 16 tumors were observed in 93 raccoons that were necropsied at zoological facilities. 10 Thirteen of these tumors were of the thyroid glands, and 1 each involved the liver, kidney, and uterus. The paucity of reported cases of neoplasia in this species may be due to genetic resistance of the raccoon to neoplasia, high turnover in free-ranging populations, or a lack of thorough pathologic examination of sufficient numbers of raccoons.The recent epizootic of raccoon rabies in the eastern USA 11 and subsequent development and experimental evaluation of a genetically engineered vaccinia-rabies glycoprotein (V-RG) recombinant virus vaccine 12 provided an opportunity to examine a large number of raccoons for pathologic changes. This communication documents adrenal gland tumors in 8 raccoons.The animals used for this investigation were obtained from 4 different locations in the eastern USA. During a 5-year period (1986)(1987)(1988)(1989)(1990), 322 raccoons (113 from Pennsylvania, 85 from Ohio, 73 from Virginia, 51 from South Carolina) were necropsied, and their tissues were examined histopathologically. The Pennsylvania raccoons were from raccoon rabies-enzootic areas and were rabies suspects. The raccoons from Ohio were obtained from the wild and were used for experimental evaluation of the V-RG vaccine, rabies pathogenesis, and adenovirus studies. 7 The Virginia and the South Carolina raccoons were obtained from off-shore islands. 12 These island raccoons were from rabies-free areas and were used to compile baseline data for pathologic conditions prior to proposed V-RG release. Included in the Virginia raccoons were 53 raccoons that were necropsied for field evaluation of the V-RG vaccine. Raccoons from all 4 locations were either subadults or adults.At the time of necropsy, representative tissue samples of all major organs 5 were placed in 10% neutral buffered formalin. The tissues were processed for routine histology, embedded in paraffin, cut at 5 µm, and stained with hematoxylin and eosin (HE) for examination by light microscopy.Gross adrenal gland lesions were observed in 5 raccoons. The lesions were visible only when the adrenal glands were bisected. On cut section of the affected gland, a white round to oval mass, approximately 0.5 cm in diameter, was present From the