Hypertrophic osteopathy and dysgerminoma in a mare.

This study describes a case of hypertrophic osteopathy in a female horse who had previously shown unexplained abdominal discomfort for a year, and was later found to have a dysgerminoma (ovarian tumour) that had spread to several lymph nodes and the main vein in the abdomen.

Hypertrophic Osteopathy

• The article reports a case of hypertrophic osteopathy, a disease that causes excessive bone growth, in a mare.
• The mare exhibited clear signs of the disease, such as bony swellings in the lower parts of both front legs (pastern area).
• Hypertrophic osteopathy often develops in response to a chronic disease or condition elsewhere in the body.

Dysgerminoma and Abdominal Discomfort

• The mare had a history of unexplained abdominal discomfort over the past 12 months.
• A diagnosis of dysgerminoma was made post-mortem. This is a type of ovarian cancer most common in young females, that is known to spread rapidly.
• The ovarian tumor had spread (metastasized) to several abdominal lymph nodes and infiltrated the posterior vena cava, the large vein that carries deoxygenated blood from the lower half of the body to the heart.

Metastasis and Pulmonary Involvement

• Even though there was no visible (gross) thoracic involvement, the researchers found microscopic tumor spread (metastasis) in some of the small blood vessels (pulmonary arterioles) in the mare’s lungs, suggesting a wider spread of the disease.

Implications of the Findings

• This case study highlights hypertrophic osteopathy as a potential physical manifestation of underlying diseases, such as ovarian cancer, in horses.
• It also emphasizes the importance of thorough examination and histological analysis to identify the primary source of the disease and any hidden metastasis.