Spontaneous Seminoma in Captive Chipmunk Tamias sibiricus

Abstract

A chipmunk presented with marked swelling of the left testicle. Histologically, the testicular mass was composed of sheets of polyhedral cells consistent with a seminoma. Invasion of the neoplastic cells to the adjacent tissues and marked atypia were noted, such as atypical karyomegalic cells and multinucleated cells, as well as abnormal mitotic figures. The neoplasm was considered to be potentially malignant. To the best knowledge of the authors, this is the first report of seminoma in a chipmunk.