Recurrent nevus: Case-report about a pagetoid form occurring from a congenital nevus in infancy

Introduction. - Recurrent nevus (RN) is a cutaneous benign tumour with similarities with malignant lesions. Typically, it occurs after a partial resection of commun-acquired nevus. Its incidence varies from 0.3 to 27% according to the studies. We present here a pediatric case of a pagetoid form of a recurrent nevus occurring from a congenital nevus. Case report. - A congenital nevus was removed from a 9-month-old girl. Pathologists concluded to a commun-acquired nevus of complete exeresis. Two other cutaneous lesions appeared and we decided to realise a total removal. Analysis showed a recurrent nevus with some atypical histological features. No recurrence has occurred during the three post-operative of follow-up. Discussion. - It is an interesting case because of the occurrence of a RN after the removal of a congenital nevus in a child. Furthermore, it displayed some atypical histological features. Practicians, such as surgeons, dermatologists or pathologists, have to be aware of the risk of misdiagnosis with this lesion, which presents some similarities with SSM melanoma. It would be interesting to determinate some markers to statuate about its benign feature. There is no management recommendation about this lesion but it seems to be necessary to remove it to eliminate a malignant tumour. (C) 2018 Elsevier Masson SAS. All rights reserved.