Excimer Laser as Adjuvant Therapy for Adult Cutaneous Langerhans Cell Histiocytosis

Abstract

An 86-year-old man with a history of chronic lymphocytic lymphoma presented for evaluation of a persistent erythematous, eroded eruption of the bilateral inguinal folds and gluteal cleft of 6 years’ duration. The lesions were characterized by burning, stinging, and weeping. Previous treatments included systemic and topical antifungal agents, topical glucocorticoid preparations, topical immunomodulators, topical antibacterial agents, barrier creams, and various emollients, with minimal benefit. Previous biopsy findings were consistent with nonspecific spongiotic dermatitis. The results of TRUE Test (Thin-layer Rapid Use Epicutaneous Test; Allerderm Laboratories Inc, Phoenix, Arizona) allergen testing were negative. The patient denied bone pain, dyspnea, cough, abdominal pain, polydipsia, polyuria, urinary retention, fevers, chills, or weight loss. Physical examination revealed circumscribed erythematous plaques with superficial maceration and erosions involving the bilateral inguinal creases and lateral scrotum, with extension to the perineum and gluteal cleft. Erythematous papules measuring 2 to 3 mm in diameter were found at the periphery (Figure 1). There was no evidence of lymphadenopathy or hepatosplenomegaly. The differential diagnosis included Langerhans cell histiocytosis (LCH), intertrigo, contact dermatitis, nutritional deficiency, Paget disease, psoriasis, erosive lichen planus, cutaneous T-cell lymphoma, and sarcoidosis. A punch biopsy specimen revealed dense aggregates of large epithelioid cells with abundant cytoplasm and reniform nuclei filling the papillary dermis (Figure 2). Similarappearing cells were also scattered throughout the epidermis and reticular dermis. Immunohistochemical staining of these mononuclear cells demonstrated CD1a and S-100 protein (Figure 3). A diagnosis of LCH was made. The patient underwent a complete evaluation, including determination of serum zinc levels, complete blood cell count, complete metabolic panel, skull films, chest roentgenogram, skeletal survey, and bone scan. There was no evidence of extracutaneous disease, and the results of all laboratory tests were within normal limits except for an elevated lymphocyte count, which was consistent with the patient’s history of chronic lymphocytic lymphoma. THERAPEUTIC CHALLENGE