Résumé : Langerhans' cell histiocytosis (LCH) may be associated with a wide range of neoplastic disorders. However, the combination of a LCH and a basal cell carcinoma (BCC) of the skin still represents a highly unusual condition. In this publication, we report the case of a 48-year-old woman who developed a localized LCH involving the area of a previously excised BCC. Although the exact pathogenesis of this peculiar association remains yet to be elucidated, the hypothesis of an exaggerated Langerhans' cell reaction in response to the underlying BCC appears to be attractive.