Adult-onset Langerhans cell histiocytosis of the sternum.

Langerhans cell histiocytosis (LCH) is a rare disease with uncertain etiology that is more prevalent in children. LCH typically invades skeletal systems, but in rare cases, it has been reported in the ribs or sternum. Optimal treatment choices for single-site, skeletal LCH are still undefined. We report a case of adult-onset LCH of the sternum. The range of surrounding soft tissue invasion was confirmed by three-dimensional fusion and reconstruction of chest computed tomography and magnetic resonance images. Our patient was successfully treated by local surgical curettage and adjuvant radiation therapy. We concluded that postoperative adjuvant radiation therapy may be advantageous for single-site LCH of bones with soft tissue invasion.