Clinical Analysis Of45Cases Of Langerhans Cell Histiocytosis And PET/CT In Diagnosis Of Langerhans Cell Histiocytosis

OBJECTIVE:The first aim of the present study is to analyze and discuss the clinical features, diagnosis, treatment and follow-up of Langerhans cell histiocytosis (LCH). The second objective is to assess the value of18F-FDG PET/CT in the diagnosis, staging before chemotherapy, and evaluation of efficacy of chemotherapy in LCH.METHODS:Clinical data including gender, age, clinical features, imaging examination of PET/CT, diagnosis, efficacy of treatments, and follow-up of45children with LCH who were admitted into the First Affiliated Hospital of Guangxi Medical University during January1,2009-January1,2014, was collected to conduct a retrospective analysis. A Chi-square test and Fisher’s exact test were performed by employing SPSS version16.0for statistical analysis. Bilateral P<0.05was considered as statistically significant.RESULTS:Fourty-five patients conformed to the classification standard of the Histiocyte Society in2009, including28males and17females (M:F ratio,1.65:1). There were22patients with Single System LCH (SS-LCH)(14boys and8girls), six of who were≤2years old, four were2～5years old, seven were 5～10years old, five patients were>10years old. And23patients were diagnosed as multisystem LCH (MS-LCH)(14boys and9girls), including13of them were≤2years old,4of them were2～5years old,2of them were5～10years old,4patients were>10years old. There was no significant difference in distribution of age or sex between SS-LCH and MS-LCH. Twenty-seven patients underwent PET/CT scans. Twelve cases took this examination before chemotherapy, including3with no obvious lesion,9with25lesions in total, which included16lesions matched with clinical features and9new lesions. Eight cases underwent PET/CT scans both before and after chemotherapy, including3with moderate response for inactivation of primary lesions and occurrence of new lesions,4with good efficacy for inactivation of all the lesions,1with poor efficacy for occurrence of new lesions without any improvement of the primary. There were7cases undergoing scans after chemotherapy, including5with good efficacy for inactivation of all the lesions,2with poor efficacy for the activation of primary lesions. The treatment methods of all included patients were as follows:3with symptomatic treatment only,2with hormone only,10with surgery only,23with chemotherapy only,7with combination of surgery and chemotherapy;26of chemotherapy patients received the regimen for LCH-III, including18had finished chemotherapy,6were undergoing chemotherapy, and3had died during chemotherapy. After finishing chemotherapy, there were16(88.89%) patients cured or better,1with moderate response and1died post-chemotherapy. The efficacy was evaluated in33patients(SS-LCH18, MS-LCH15), including23cured or better (SS-LCH15, MS-LCH8),5with reccurence(SS-LCH2, MS-LCH3),4dead (MS-LCH),1with liver dysfunction after discontinuing drugs(SS-LCH).12patients lost follow-up(SS-LCH4, MS-LCH8). CONCLUSIONS(1) There was no significant difference in distribution of age or sex between SS-LCH and MS-LCH.(2) Bone is the mainly damaged organ in Langerhans cell histiocytosis, and liver and spleen are also likely to be involved.(3)18F-FDG PET/CT plays an important role in the staging and therapeutic evaluation of LCH pre-and post-chemotherapy.(4) The prognosis of SS-LCH is better than MS-LCH.