Senile sebaceous nevus degenerating to a pseudo glandular basal cell carcinoma

epidermis and dermis, with a triphasic evolution: alopecic patch with underdeveloped adnexal structures. In puberty, the second phase shows a proliferative and veracious plaque. While the third phase is characterized by the occurrence of benign or more rarely invasive tumors in the preexistent plaque. Dermoscopy finds an important place in the characterization of these stages of evolution, and especially in the detection of transformation. 10-20% of sebaceous nevus is transformed into benign or malignant tumors that Abstract Jadassohn nevus is a congenital hamartoma that is characterized by natural evolution in three stages, with a risk of malignancies occurring in the last phase. This benign adnexal tumor often affects the face and scalp. Dermoscopy can provide a major help for detecting transforming tumors. We report the case of a senile sebaceous Nevus which has been diagnosed after the occurrence of Basal cell carcinoma in a 60 years old man. The originality of this observation remains in the rarity of the pseudo glandular basal cell carcinoma that, in the best of our knowledge, has never been reported in underlying nevus sebaceous.