ALK positive anaplastic large cell lymphoma of the thoracic spine

Primary bone lymphoma (PBL) is an uncommon extra nodal disease that represents about 1-3% of lymphoma cases. Imaging findings are variable and non-specific. Computed tomography may demonstrate lytic lesions with sequestra and periosteal reaction. On magnetic resonance imaging, lesions are T1WI hypointense and T2WI hyperintense, related to peritumoral edema or bone marrow replacement. Rarely lesions may have associated fibrosis and show a more hypointense signal pattern on T2WI. After administration of contrast, PBL tends to enhance avidly. We present a case of a 24 years old African American female patient with history of back pain. Initial imaging examinations showed lesions involving the T12 and T11 vertebral bodies with initial negative biopsy results. One month later, the patient returned with worsening back pain, and the follow up studies depicted collapse of the T12 vertebral body. A diagnosis of anaplastic large cell lymphoma in T12 was made. A brief review of the literature, imaging and pathological findings, and treatment options are also discussed.