Adrenal Gland Adenomas in Raccoons (Procyon Lotor) from the Eastern United States

Abstract

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

Pathology of neurologic disorders of raccoons (Procyon lotor)

“…Neoplastic lesions have infrequently been documented in the family Procyonidae . With the exception of thyroid adenomas 76,85 and adrenal gland adenomas, 64 neoplasia appears to be rather rare in raccoons, and only infrequent case reports have been documented. In a retrospective survey of over 400 raccoon necropsies, 13 only 1 astrocytoma of the brain was found.…”

Procyonidae, Viverridae, Hyenidae, Herpestidae, Eupleridae, and Prionodontidae

“…Reported neoplasms in these groups include lymphoma ( Fig. 12.3), carcinomas of the urinary bladder, gastrointestinal tract (including anal sac glands), mammary gland, hepatobiliary, pulmonary, and renal systems (Aihara, 2009;Bjornson et al, 1999;Boonsri et al, 2013;Childs-Sanford et al, 2005;Chu et al, 2012;Dadone et al, 2014;Dawood, 2012;Effron et al, 1977;Goodnight et al, 2013;Hamir and Rupprecht, 1995;Hamir et al, , 2008Howard et al, 2007;Klaphake et al, 2005;Lombard and Witte, 1959;Marrow et al, 2014;Montali, 1980;Singh et al, 2005;Singleton et al, 2007;Thompson et al, 2016;Wadsworth et al, 1982;Wang et al, 2001). A single case of uterine adenocarcinoma in a captive coati associated with implantation of the contraceptive melengestrol acetate has also been reported (Chittick et al, 2001).…”

Diffuse Large B-Cell Lymphoma (DLBCL) in an Aged Raccoon (Procyon lotor)

“…In raccoons (Procyon lotor), neoplasms are rarely documented but the occurrence of cancer in raccoon populations might be underestimated due to the difficulty in estimating morbidity and mortality rates related to spontaneous diseases in wildlife [3]. Recent reports of neoplasm in raccoons include descriptions of raccoon polyomavirus-associated brain tumors [4][5][6], and a few offers concerning epithelial neoplasms [7][8][9]. Regarding round cell tumors, there are only two other earlier cases of lymphosarcoma in raccoons, both of which lack immunophenotype characterization [10,11].…”