Two distinct carcinomas of mammary gland origin in a California sea lion
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Published on: October 16, 2010
Michiko Matsuda1, Shinichiro Hashiura, Yumi Une
1Department of Veterinary Pathology, School of Veterinary Medicine, Azabu University, 1-17-71 Fuchinobe, Sagamihara, Kanagawa 229-8501, Japan. matsuda@nval.go.jp
Abstract:
Two histologic types of mammary cancer were encountered in an aged captive California sea lion (Zalophus californianus). A cancer with myoepithelial cell proliferation, which had metastasized to distant viscera, was located in the left cranial mammary region. Another cancer without myoepithelial cell proliferation was located in the right posterior mammary region, formed secondary nodules, and had metastasized to a regional lymph node. The presence of two different neoplasms in this sea lion is unusual.
