[Clinicopathologic analysis of Langerhans cell histiocytosis in adults].

OBJECTIVE: To explore the clinical features, pathomorphology, immunohistochemical characteristics and prognosis of Langerhans cell histiocytosis (LCH) in adults. METHODS: Twenty-three cases of adult LCH were retrieved from Ningbo Diagnostic Pathology Center during the period from January 2005 to December 2011. And their clinical presentation, pathomorphology and immunohistochemical characteristics were analyzed. RESULTS: The mean age of patients was 37.2 years (range: 20 - 58). The male-to-female ratio was 1.6:1. Of 23 LCH patients, 26 lesions were found including 14 bone tissue lesions (53.8%), followed by 4 lymph node lesions and 4 skin lesions (both 15.4%), as well as 1 soft tissue, liver, parotid and buccal lesion respectively (all 3.8%). Clinically, uni-system and unifocal disease was predominant (19 cases, 82.6%), followed by uni-system and multifocal disease (1 case, 4.3%), multi-system disease (3 cases, 13.0%). Histologically, all cases of LCH revealed diffused distribution of Langerhans cells, accompanied by a variable number of eosinophils, lymphocytes, neutrophils and multinucleated giant cells. Immunohistochemically, the expression of CD1a, Langerin, S-100 protein and CD68 was 100% (23/23), 100% (20/20), 95.6% (22/23) and 90.5% (19/21) respectively. All lesions were treated by surgical therapy. Sixteen patients were available for follow-up examination and 14 patients survived. The 3 and 5-year cumulative survival rates were 92.9% and 79.6% respectively. CONCLUSIONS: LCH of adults occurs predominantly in bone and presents mainly as uni-system or unifocal defects. Surgical excision is generally effective and the prognosis is fair.