Follicular baso-squamous melanocytic tumour of the skin.

Aims: We describe a previously unrecognized pigmented tumour of the skin and suggest a possible relationship with the follicular bulb.

Methods And Results: A pigmented epithelial neoplasm clinically simulating a malignant melanoma of the skin was present in a 92-year-old woman, on her left leg. It was composed of three cell types: squamous cells with trichilemmal keratinization, basaloid cells and dendritic melanocytes. The presence of three cell types was confirmed by immunohistochemistry and electron microscopy.

Conclusions: The tumour showed differentiation towards the hair follicular bulb and the descriptive term of follicular baso-squamous melanocytic tumour is suggested.