[A case of cellular blue nevus with bone and meningeal invasion]

The blue naevus is an essentially benign tumour. However, the cellular variety may rarely undergo malignant transformation. The authors report an unusual case of blue naevus in terms of size and evolution. This tumour which involved the occipitovertebral and parotid regions infiltrated underlying tissues and organs, in particular, the occipital bone, the dura mater and the parotid gland. The clinical, histological and histogenic problems associated with the blue naevus are discussed. There are only scattered reports of tumours of a similar nature in the literature and for this reason we felt that this case merited being reported.