Oral Langerhans Cell Histiocytosis in Two Pediatric Patients.

We report two cases of Langerhans cell histiocytosis (LCH) in the oral cavity of children. An 11-month-old girl was referred for evaluation of a nodular and sessile lesion in the alveolar ridge covering the primary left mandibular central incisor. The second patient was a seven-year-old boy with an ulcerated lesion in the gingiva covered by necrotic areas, extending to the sulcus of the vestibule. The patients underwent incisional biopsies and histopathological exams showed a proliferation of Langerhans and eosinophil cells, suggesting a diagnosis of LCH, which was confirmed by positive immunohistochemical expression of S100 and CD1.