Langerhans cell histiocytosis: unusual dorsal spine localization in an adult male.

This case report describes the clinical, imaging, and pathological features of a case of Langerhans cell histiocytosis affecting a patient suffering from chronic thoracic spine pain. Spinal localizations of Langerhans cell histiocytosis have been rarely described and they are usually characterized by involvement of vertebral bodies with osteolytic lesions. Our case presented with several unusual features that delayed the diagnosis, including the age of patient and the involvement of left T10 costovertebral junction with relative sparing of vertebral body and costal bone. The clues for diagnosis were represented by increased signal intensity both on T ₂W fat-saturated and T ₁W images after administration of gadolinium. The diagnosis was finally confirmed by means of percutaneous biopsy with subsequent histological/immunohistochemical study.