Langerhans cell histiocytosis on the penis: a case report

The patient was a 13-year-old boy who had a history of lymph node, femur bone, and pituitary-thalmic axis lesions from Langerhans cell histiocytosis who noticed a painful nodule on the prepuce of his penis. The histological and immunohistochemical examination fulfilled the criteria of Langerhans cell histiocytosis.We herein describe the case reported of Langerhans cell histiocytosis on the penis.Langerhans cell histiocytosis (LCH) is characterized by an organ-specific infiltration of cells with many morphological features and immunohistochemical markers of Langerhans cells. Clinically, LCH ranges from self-healing lesions to a multi-system involvement with organ dysfunction resistant to current therapies. The lesions appear in multiple organs, for example in the bones, skin, and lungs, but a lesion localized on the penis is uncommon. We herein report a case of LCH on the penis.A 13-year-old boy presented with a nodular lesion on the prepuce of his penis. A diagnosis of LCH had been made at the age of 3 years. The first lesion was on a cervical lymph node. After the administration of chemotherapy with vincristine, cyclophosphamide, and predonisone, the lesion resolved. When the patient was 11 years old, he restarted chemotherapy (cyclophosphamide and 6-mercaptopurine) because of a recurrent lesion in the femur bone and along the pituitary-thalmic axis. At this time, he noticed a painful nodule, 5 mm in diameter, which was elastic, hard, and reddish, with a smooth surface (Fig. 1). Surgical resection of the nodule in the foreskin, without amputation or circumcision, was performed. Histologically, the lesions consisted of diffuse infiltrates of Langerhans cells with indented or grooved nuclei and eosinophilic or pale cytoplasm. Also present were various numbers of eosinophils, lymphocytes, and neutrophils. The lesions represented stromal edema and mild fibrosis. Their surface was focally eroded. Scattered vascular proliferation was present (Fig. 2). Both S-100 protein