Fine-needle cytology of cutaneous juvenile xanthogranuloma and langerhans cell histiocytosis.

BACKGROUND: In pediatric patients, a cutaneous nodule is usually diagnosed by performing an excisional biopsy, but fine-needle cytology (FNC) is a safer and noninvasive diagnostic method widely used to obtain diagnostic specimens with little stress to the patient. The authors compared the ability of FNC and biopsy to differentiate Langerhans cell histiocytosis (LCH) from juvenile xanthogranuloma (JXG). METHODS: Correlating cytological results with histological findings, the authors reviewed 27 patients (15 males and 12 females; mean age, 37 months; range, 1 month to 14 years) admitted to the University of Padua Department of Pediatrics from 1998 to 2010. RESULTS: Cytology smears were adequate in all 27 (100%) patients: 14 (52%) were classified as having JXG, 12 (44%) as having LCH, and 1 (4%) as having a doubtful finding. A biopsy was also performed in 20 of these patients, and in all but 1, the 2 methods were completely concordant. CONCLUSIONS: FNC is safe and useful in the diagnostic workup of pediatric patients with cutaneous nodules and has no contraindications to its use as the initial diagnostic procedure. Cancer (Cancer Cytopathol) 2011;119:134-40. (C) 2010 American Cancer Society.