Lobular capillary haemangiomas in young horses.

This study discusses seven cases of skin tumours (haemangiomas) found in young horses, characterized by unique structures comprised of small blood vessels. The researchers suggest that these tumours share features with certain conditions seen in cows and humans, and they propose the name “lobular capillary haemangioma” for this specific type of skin tumour.

Background of the Research

• This study looks into seven instances of a specific type of skin tumour known as haemangiomas in young horses. This tumour, according to the researchers, is predominantly made up of small capillary-sized blood vessels and fibrous tissues connecting these vessels.

Key Findings of the Study

• The researchers observed that these lesions are notable for being scattered, easily distinguishable, but not encompassed within a distinct boundary or capsule. These characteristics differentiate them from other types of skin anomalies.
• In a single case, the researchers found a more cellular variant of the haemangioma, showing lesser capacity for forming new blood vessels (vasoformative capacity).

Comparative Analysis

• The researchers draw a parallel between these skin tumours in horses and two other conditions found in different species. In their morphological features, these haemangiomas appear similar to bovine cutaneous angiomatosis, a condition in cows, and human granuloma pyogenicum, a skin condition in humans.

Proposed Terminology

• The team suggests the term “lobular capillary haemangioma” as an appropriate name for these skin tumours, emphasizing that these are indeed vascular tumours, not hamartomas (a benign, focal malformation that resembles a neoplasm in the tissue of its origin) or granulation tissue (the new connective tissue that forms on the surface of a wound).

Diverse Nature of the Tumour

• In one tumour, the researchers discovered both capillary structures and larger, cavernous vascular structures. This suggests a dual nature for these haemangiomas – they can be both capillary (consisting of small blood vessels) and cavernous (consisting of large, often irregular blood-filled spaces).