Chemotherapy-refractory cutaneous Langerhans cell histiocytosis treated with radiotherapy

Abstract

Langerhans cell histiocytosis (LCH) is a clonal, neoplastic proliferation of dendritic cells exhibiting morphologic and immunophenotypic features of Langerhans cells. Nezelof et al were the first to correctly recognize that the Langerhans cell, a member of bone-marrow derived dendritic cells and an important antigen-presenting cell, was, in fact, the cell of origin for LCH.1,2 LCH has a variety of presentations, ranging from isolated or multifocal bone disease to systemic involvement. Prognosis is variable and is influenced by multiorgan involvement. Cutaneous involvement is also common in LCH and may occasionally be unresponsive to standard treatments, including steroids, chemotherapy, and psoralen and ultraviolet A (PUVA) therapy. When unchecked, however, disease progression in the skin can lead to serious morbidity, including pain, infection, and disfigurement. Given the relative radiosensitivity of lymphoid malignancies, radiation has been utilized to help with symptoms and tominimize the burden of disease.3-5 Nonetheless, there are very little data on the use of radiation for skin-limited LCH and most of it is based on widely disparate irradiation methods from, primarily, the palliative setting. Here, we