儿童四肢长骨郎格汉斯细胞组织细胞增生症影像表现与临床病理对照分析

Imaging findings of Langerhans cell histiocytosis in limbs of children： comparison with clinical and pathological findings

目的探讨儿童四肢长骨郎格汉斯细胞组织细胞增生症（Langerhans cell histiocytosis，LCH）的影像表现及临床病理特点，提高影像诊断水平。方法回顾性分析12例经手术及病理证实的四肢长骨LCH患儿临床及影像资料。本组病例中10例行X线检查，9例行CT检查，7例行MRI检查，对其影像特征进行分析。结果本组单发病灶7例，其中胫骨4例、桡骨2例、尺骨1例；多发病灶5例，均为长骨病变，共12处病灶，股骨6处、肱骨3处（其中1处累及骨骺）、胫骨2处、桡骨1处。X线及CT检查病灶表现为溶骨性、虫蚀样或膨胀性骨质破坏，骨膜反应常见；周围软组织肿胀常见，仅1例伴软组织肿块形成。MRI检查病灶表现为T1WI等或稍低信号，T2WI为高信号或混杂高信号。初次就诊，根据影像诊断LCH6例、感染性病变6例。12例患儿治疗后均定期随访，单发病例且病程长者预后较好。结论四肢长骨LCH好发于长骨骨干及干骺端，表现为溶骨性、虫蚀样或膨胀性骨质破坏伴软组织肿胀或肿块形成，发病部位及影像征象具有一定特点，但与恶性骨肿瘤等鉴别仍有一定难度。综合X线、CT及MRI表现能提高术前诊断率，并为评估预后提供重要依据。

Objective To study the imaging findings, clinical and pathological characteristics of langerhans cell histiocytosis （LCH）in limbs of children, and to improve the imaging diagnostic accuracy of LCH . Methods Imaging findings and clinical data of 12 patients with limbs LCH were analyzed retrospectively. X-ray examination was performed in 10 cases, while 9 cases underwent CT and 7 cases underwent MRI examination. All imaging findings were analyzed. Results Seven lesions were solitary, including 4 lesions in the tibia, 2 in the radius and lin the ulna. Five cases had limbs lesion in multiple sites, which included 12 bone lesions in total, with 6 lesions in the femur, 3 in the humerus （1 case involved the epiphysis）, 2 in the tibia and lin the radius. The X-ray or CT images of the lesions showed osteolytic destruction and swelling of the bone, which was commonly associated with the reaction of periosteum. Eleven cases were with peripheral soft tissue swelling, and one case had soft tissue mass. The lesions showed low signal on T^WI and high signal or mixed signal on T2WI. Six cases were diagnosed as LCH at the first time and the other 6 cases were diagnosed as infectious lesions. Twelve cases were regularly followed up after the treatment, and the prognosis of the patients with single lesion was better. Conclusions LCH of limbs usually involves diaphyseal and metaphyseal bone. The imaging features include osteolytic destruction and swelling of the bone, with peripheral soft tissue swelling or mass of the soft tissue. Although LCH of limbs has some specific imaging features, it is difficult to differentiate it from malignant bone tumors. Multi-imaging modalities such as radiography, CT and MRI imaging may suggest the diagnosis and provide important information for evaluating prognosis.