Incidence of epithelial tumor developing on the eye-ball, cornea, and conjunctiva has been recognized among cattle in America and it. has been established that many, if not all, cases of benign neoplasm, if left untreated, will undergo a transformation into carcinoma. The affected eye was descrivd as cancer eye. No cancer of the orbital region has not been found in Japan.
The authors encountered a case of malignant neoplasm on the right nictitating membrane of a 9-year-old Holstein cow at the Breeding Stock Farm of the Prefecture of Saga. This report deals with clinical, anatomical, and histological views on this case.
The neoplasm grew on the nictitating membrane at first and then gradually affected the neighboring orbital region. It was metastasized to the right part of the parotid and submaxillary lymph nodes. Histopathological observation disclosed that this neoplasm belonged to glandular-cell carcinoma, or carcinoma simplex, which was different from squamous-cell carcinoma of the typical cancer eye found in America. No bacteria nor virus was isolated from this case in mice and hen's eggs. Cultivation in vitro of this neoplasm was not successful in No.199 media containing 30 per cent bovine serum by the plasma clot method and the trypsindispersed method.
