Langerhans Cell Histiocytosis of the Clavicle

We report a rare case of solitary Langerhans cell histiocytosis (LCH) involving the clavicle of an adult female. The patient was a 32-year-old female presenting with 1 month history of progressive pain, swelling, and tenderness in the region near the left sternoclavicular joint. Radiograph, computed tomography, and magnetic resonance imaging showed an osteolytic lesion in the clavicle with tumor extension and soft tissue edema. Surgical curettage of the lesion was performed, and the histopathologic diagnosis was LCH. Because of its rarity and possibly variable presentation, LCH should be included and considered in the differential diagnosis when we encounter a clavicle lesion. (Medicine 93(20):e117) Abbreviations: CT = computed tomography, EG = eosinophilic granuloma, LCH = Langerhans cell histiocytosis, MRI = magnetic resonance imaging. INTRODUCTION Langerhans cell histiocytosis (LCH) is a rare disease of unknown etiology with an estimated annual prevalence of 1 case per 560,000 in adults and encompasses 3 disorders: eosinophilic granuloma (EG), Hand–Schuller–Christian syndrome, and Letterer–Siwe syndrome according to their clinical and pathologic features. One of the most frequent presenting imaging features in adults is skeletal involvement with lytic lesions, but clavicle lesions are extremely rare, especially in adults. Till now, almost no related articles report characteristic imaging of LCH in clavicle in adults. We report 1 female adult patient with solitary clavicle EG, with a literature review. CASE REPORT A 32-year-old female adult presented with 1 month history of progressive pain, swelling, and tenderness in the region near the left sternoclavicular joint. The patient denied fever, chills, night sweats, weight loss, and fatigue. There was no history of trauma. The posterior–anterior radiograph showed ill-defined osteolytic lesion without sclerotic margin in the left clavicle with soft tissue swelling above the lesion (Figure 1). Computed tomography (CT) multiplanar reconstruction images revealed the osteolytic lesion in the diaphysis of the left clavicle with surrounding swelling soft tissues (Figure 2). Moreover, there was no osteosclerosis and periosteal reaction. On magnetic resonance imaging (MRI), Editor: Liang Han. Received: June 21, 2014; revised: August 12, 2014; accepted: August 13, 2014. From the Department of Radiology (SW, WZ, LZ, ZL), First Affiliated Hospital of Dalian Medical University; and Department of Radiology (SN), Second People’s Hospital of Dalian, Dalian, China. Correspondence: Weisheng Zhang, Department of Radiology, First Affiliated Hospital of Dalian Medical University, Dalian 116011, China (e-mail: [email protected]). The authors have no funding and conflicts of interest to disclose. Copyright © 2014 Wolters Kluwer Health | Lippincott Williams & Wilkins. This is an open access article distributed under the Creative Commons Attribution License 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. ISSN: 0025-7974 DOI: 10.1097/MD.0000000000000117 A