Correspondence Fine needle aspiration cytology of Langerhans cell sarcoma DOI:10.1111/j.1365-2303.2006.00403.x Dear Editor, Langerhans cell (LC) sarcoma is a neo- plastic proliferation of LC with evident malignant histological features. 1,2 It is considered as an aggres- sive variant of LC histiocytosis and the World Health Organization classification refers to it as a specific entity. 1 Histology reveals an anaplastic neoplasm and immunohistochemical studies are necessary for a precise diagnosis. In some cases, nuclear indentations may suggest the diagnosis. In this report, we describe a patient with LC sarcoma that was initially evaluated by fine needle aspiration cytology (FNAC). The tumour presented as a cervical adenopathy and resulted in a troublesome cytological diagnosis. The rarity of this neoplasm is reflected by the existence of very few previous cytological descriptions. 3 A 67-year-old man was referred to our laboratory for FNAC of a laterocervical mass. Physical examina- tion revealed a cervical 3 · 4 cm, non-mobile, firm mass that was aspirated by a pathologist by using a 23-gauge needle. At the time of aspiration no other lesions were present. Smears were hypercellular and showed a single cell population of large neoplastic cells. Naked nuclei were present but most cells had a small to moderate amount of deeply stained cytoplasm (Figure 1). Nuclei were pleomorphic with irregular contours and indentations (Figure 2). A few cells were binucleated and others had a multilobated nucleus. Mitotic figures were common. In addition to the neoplastic population, small lymphocytes, neutrophils and a few eosinophils were present. The background was granular, with numerous necrotic cells. Lympho- glandular bodies were not a prominent finding. These cytological features raised the possibilities of high- grade, non-Hodgkin’s lymphoma and metastatic car- cinoma. Immunocytochemistry revealed an intense expression of CD45 in the neoplastic cells. It was performed on alcohol-fixed material using a strept- avidin–biotin method. Cytokeratins AE1/A3 were not expressed. A preoperative cytological diagnosis of Ômalignant, high-grade lymphoproliferative neoplasmÕ was given. Surgical biopsy revealed a diffuse growth of large, anaplastic cells with a moderate amount of cytoplasm and areas of necrosis (Figure 3). Although a Correspondence: J. A. Jime ´ nez-Heffernan, Servicio de Anatomı ´a Patolo ´ gica, Hospital Universitario, Donantes de Sangre s/n, 19002 Guadalajara, Spain. Tel.: +34 949209220; Fax: +34 913572145; E-mail: jjheffernan@yahoo.com Figure 1. Smear showing a single cell pattern of large neoplastic cells with moderate amount of cytoplasm and a few small lymphocytes (Diff-Quik, ·177). Figure 2. Some neoplastic cells showed nuclear indentations and multilobated forms (Diff-Quik, ·200). Cytopathology 2008, 19, 59–64 ª 2008 The Authors Journal compilation ª 2008 Blackwell Publishing Ltd 59