[Langerhans cell histiocytosis involving the oral and maxillofacial region: an analysis of 12 cases].

OBJECTIVE: To study the clinical features of Langerhans cell histiocytosis (LCH) involving the oral and maxillofacial region in children. METHODS: A retrospective analysis was performed for the clinical data of 12 children with LCH involving the oral and maxillofacial region who were hospitalized and treated from September 2012 to September 2017, including clinical manifestations, pathological features, treatment and prognosis. RESULTS: Of the 12 children, 8 (67%) had multiple system involvement and 7 (58%) had the involvement of organs at risk. Bone was the most common affected site (11 children, 92%), among whom 7 children had the involvement of the mandible. Oral soft tissue involvement manifested as gingival ulcer or hyperplasia in 4 children, loose teeth in 5 children, oral mucosal lesions in 2 children, and nodular lesions in 1 child. Pathological examination showed positive CDla in 11 children and positive CD207, CD68, S-100, and LCA in 12 children. Surgery combined with chemotherapy was the major treatment method, and surgical resection alone was performed for focal lesions. After treatment, 11 children were cured or improved and 1 gave up treatment and was lost to follow-up. No recurrence was observed. CONCLUSIONS: LCH children with oral and maxillofacial involvement often have the involvement of multiple systems and organs at risk, with the mandible as the most common affected site. These children may also have the involvement of gingiva, oral mucosa and teeth. Surgery combined with chemotherapy is the major treatment method, and the patients generally have a good prognosis without recurrence.