Langerhans cell histiocytosis of skin: a clinicopathologic analysis of five cases.

ABSTRACT

BACKGROUND AND AIMS: Langerhans cell histiocytosis (LCH) is a rare proliferative disorder of histiocytes characterized by a proliferation of abnormal and clonal Langerhans cells. We retrospectively studied clinicopathologic features of this disorder in five cases. METHODS: Clinical and histopathological findings of five cases of cutaneous LCH were reviewed based on the hospital records. RESULTS: The age of patients ranged from 28 days to 5 years and M F ratio was 11.5. Clinically, the diagnoses suggested were histiocytosis, varicella, transient neonatal pustular melanosis, keloid, sarcoidosis, seborrheic keratosis and LCH. The most common type of skin lesion was a generalized papular lesion. Histologically, all cases showed aggregates of large mononuclear histiocytes (Langerhans cells) with reniform, irregular, cleaved nuclei and abundant eosinophilic cytoplasm. There was multi-systemic involvement in two patients and single-system involvement in three patients. CONCLUSION: Cutaneous lesions may be the sole presenting feature of LCH. Diagnosis is based on demonstration of S-100 positive histiocytes.