Veterinary oncology: a survey

Spontaneous squamous cell carcinomas of the oral region in domestic animals: a review and consideration of their relevance to human research

Spontaneous squamous cell carcinomas of the oral region in domestic animals have the potential of providing additional information about the pathology of oral cancer and may be useful in therapeutic research. Moreover, they exhibit definite advantages over chemically induced tumors in rodents. This article provides background information on spontaneous oral squamous cell carcinomas in dogs, cats, cattle, horses and sheep and then discusses the use in research of such tumors in dogs and cats. These two species are potentially the most useful because they are numerous, suffer quite commonly from squamous cell carcinoma of the oral cavity and oropharynx, and are usually allowed to live approximately normal life spans. Moreover, they are being treated routinely in veterinary hospitals.

Histopathology of melanocytic lesions in goats and establishment of a melanoma cell line: a potential model for human melanoma

Melanocytic cells from white Angora goats were studied in vivo and in vitro. The histopathology of pigmented areas of skin from the most common sites of melanoma (solar-exposed areas of the ear, face, and perineum) resembled that of the epidermal melanocytes in Hutchinson's melanotic freckle in humans. Seven melanoma biopsies from 6 Angora goats showed histopathological features in common with human melanoma. A melanoma cell line, GM-1, was established in culture from a lymph node metastasis obtained from an animal that had a primary tumor excised and later developed extensive metastatic disease. GM-1 cells were mainly diploid, amelanotic, proliferated rapidly, spontaneously formed vacuolated cells, and were tumorigenic in nude mice. The species of origin of the GM-1 line was confirmed by isozyme profiles. GM-1 cultured cells and the original biopsy both expressed S-100 protein and tyrosinase antigen. Using GM-1 cells as the immunogen, a monoclonal antibody (MoAb 1F1) was derived that reacted strongly with a 116 kDa antigen in 50% of the GM-1 cells, but had little activity with goat fibroblasts (GM-F) or with human melanoma cells. GM-F, on the other hand, yielded more intense staining than GM-1 with an intermediate filament antibody (IFA), reacting with a 58 kDa antigen in both cell lines. The sensitivity of GM-1 to anticancer agents was similar to that of human melanoma cells. The pathology of caprine melanoma and its association with sun-exposed sites in relatively young animals suggest that it may be a suitable model for studying induction of melanoma by natural sunlight.

Malignant melanoma in goats: a clinico-pathological study

The clinicopathological features of 62 cases of malignant melanoma in goats in Sudan are described. The tumours occurred most frequently in grey or brown goats. The predilection site was the perineum. The tumour invaded locally and metastasized through lymphatics and blood vessels. Surgical excision of the tumour was followed or preceded by lymphadenectomy in some cases. The tumour was highly malignant and carried a poor prognosis. Possible aetiological factors are discussed.