4 Risk factors for melanomas in most domestic animals have not been fully described. ![]() In humans, risk factors such as race, lack of skin pigmentation, excessive exposure to sunlight, and presence of preexisting nevi have been described. ![]() The mass was diagnosed as a malignant melanoma arising from the horn base with local spread to the frontal sinuses and metastases to the parotid salivary gland, regional lymph nodes, and liver ( Figs. No oral masses or other epithelial masses were present. As a positive control, melanocytes from the skin of an adult caprine were labeled appropriately using the same technique. Negative controls included nonspecific immunoglobulin as the primary antibody. The primary antibody was used at a 1:100 dilution. Deparaffmized sections were labeled for Melan A using the indirect immunoperoxidase method and using the envision polymer (Dako) as the second step. The tumor cells were positive for Melan A by immunohistochemical staining. Histologically, the masses consisted predominantly of moderately pleomorphic, polyhedral-shaped to spindle-shaped cells containing variable amounts of dark brown intracytoplasmic pigment granules. Multiple black foci (0.5 to 1.0 cm) were observed in the liver. The left maxillary premolars and molars were loosened from the periodontia. ![]() The submandibular lymph node and the left parotid salivary gland were markedly enlarged, firm, and diffusely black on cut surface. ![]() A firm black mass, approximately 3 × 3 × 2 cm, extended from the base of the horn subcutaneously over the frontal bones, invading the bones and infiltrating into the frontal sinuses as multiple nodules ranging from 0.5 to 1.0 cm in diameter. There was a perforating corneal ulcer approximately 1 cm in diameter on the left eye. On gross postmortem examination, the tissue at the site of the horn fracture was ulcerated and extensively discolored black. All subjects Allied Health Cardiology & Cardiovascular Medicine Dentistry Emergency Medicine & Critical Care Endocrinology & Metabolism Environmental Science General Medicine Geriatrics Infectious Diseases Medico-legal Neurology Nursing Nutrition Obstetrics & Gynecology Oncology Orthopaedics & Sports Medicine Otolaryngology Palliative Medicine & Chronic Care Pediatrics Pharmacology & Toxicology Psychiatry & Psychology Public Health Pulmonary & Respiratory Medicine Radiology Research Methods & Evaluation Rheumatology Surgery Tropical Medicine Veterinary Medicine Cell Biology Clinical Biochemistry Environmental Science Life Sciences Neuroscience Pharmacology & Toxicology Biomedical Engineering Engineering & Computing Environmental Engineering Materials Science Anthropology & Archaeology Communication & Media Studies Criminology & Criminal Justice Cultural Studies Economics & Development Education Environmental Studies Ethnic Studies Family Studies Gender Studies Geography Gerontology & Aging Group Studies History Information Science Interpersonal Violence Language & Linguistics Law Management & Organization Studies Marketing & Hospitality Music Peace Studies & Conflict Resolution Philosophy Politics & International Relations Psychoanalysis Psychology & Counseling Public Administration Regional Studies Religion Research Methods & Evaluation Science & Society Studies Social Work & Social Policy Sociology Special Education Urban Studies & Planning BROWSE JOURNALS
0 Comments
Leave a Reply. |