Penile juvenile xanthogranuloma and neurofibromatosis type-1: risk association with juvenile myelomonocytic leukaemia?

Juvenile xanthogranuloma (JXG) is a benign, self-healing, non-Langerhans cell histiocytosis characterized by accumulation of lipid-laden macrophages. It occurs most commonly on the head and neck of infants and young children and resolves spontaneously without treatment [1]. Lesions may be single or multiple, congenital or acquired. Size varies from few millimetres to several centimetres. Two main clinical forms have been described: a small nodular form (60%) and a large nodular form (40%). Mixed forms and JXG “en plaque” have been described [2]. Moreover, different morphological types of JXG and atypical locations have been reported [3,4]. The first case of penile JXG was reported in 1993 [5]. The typical histologic appearance of JXG consists of a dense dermal infiltrate of foamy histiocytes, foreign body and Touton giant cells, the latter being nearly pathognomonic of JXG [1]. Several authors have reported the occurrence of café-au-lait macules (CALMs) or neurofibromatosis type-1 (NF-1) in patients with JXG [3,4,6]. In this report we describe a 7-year-old boy with a solitary penile JXG presentation at age of 2 years in association with NF-1. Case report