A benign hamartoma of skin. A vascular naevus has an extensive capillary network and as a result is red (‘strawberry birthmark’; sometimes the much more extensive ‘port wine stain’). A mole is a nonmalignant pigmented naevus, a cluster of highly pigmented melanocytes. A blue naevus is an unusual form of mole in which the melanocytes are deep in the dermis.
Subjects: Medicine and Health.