Vascular anomalies

Vascular anomalies are classified into two main groups: vascular tumours and vascular malformations.

Vascular malformations occur because of an error in the development of vascular embryogenic tissue, meaning that they are present at birth. Sometimes they are not visible at the time of birth and appear a bit later. They are considered vascular malformations because when they are studied under the microscope, an increase in vascular structures can be seen, and also because they grow abnormally, even though the endothelial cell count is normal. They grow proportionally with the child, since the abnormal vessels do not multiply at a faster rate. Vascular malformations do not disappear by themselves.

Conversely, in vascular tumours, an increase in endothelial cells is observed under the microscope, and it has been observed that they multiply in an accelerated manner. They tend to appear after the baby is born, a period that can vary from just a few weeks to several months or many years. But this is not the defining factor of a vascular tumour, as there are some tumours that are present at birth, such as congenital haemangiomas, kaposiform haemangioendothelioma, tufted angioma and certain pyogenic granulomas. Some vascular tumours may show regression (they may decrease or disappear) spontaneously when their cells suffer apoptosis (cell death).

We will describe tumours and malformations as different entities.