Tumours of the dermis

 Benign

Developmental abnormalities of blood vessels

These are either present at birth or appear soon after. They can be classified clinically (Table 18.6) but there is no good clinicohistological correlation. A capillary malformation is composed of a network of capillaries in the upper and mid dermis. A capillary cavernous haemangioma has multiple ectatic channels of vary-ing calibre distributed throughout the dermis and even the subcutaneous fat.

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