Adult Langerhans cell histiocytosis involving adjacent vertebra on F-FDG PET/CT imaging.

Langerhans cell histiocytosis (LCH) of the spine involving the intervertebral disk and adjacent vertebra is rare in adults. We report a case of a 56-year-old woman with neck pain and right upper limbs numbness. Fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography (F-FDG PET/CT) showed an osteolytic bone lesion in the fourth cervical vertebra (C4) with soft-tissue mass, invading the adjacent intervertebral disc and posterior vertebral body of C3, compressing dural sac and cervical spinal cord. The lesion showed increased F-FDG uptake with a maximum standardized uptake value (SUVmax) of 6.75. Subsequently, the histopathologic examination confirmed the diagnosis of LCH.