gms | German Medical Science

Objective: Inflammatory pseudotumor represents a heterogeneous group of benign tumor-like lesions with diverse localization and histopathological presentation. The aetiology of inflammatory pseudotumor still remains unclear. It is a rare disease occurring in various organs such as the lung, gastrointestinal tract, thyroid gland, kidney, lymph nodes, and skin. Till date, only a few cases with spinal manifestation have been described. Hence, it is important to consider inflammatory pseudotumor as a differential diagnosis to provide the exact therapy regimen.

Methods: An 80-year-old female patient presented with chronic thoracolumbar back pain for 10 years that aggravated in terms of spinal claudication. The MRI revealed a tumor-like lesion in the T11–T12 vertebrae, suggesting the presence of a meningioma. Based on the clinical presentation and the MRI findings, we decided to perform a resection, followed by a histopathological investigation, to define the exact pathology to suggest the accurate therapy.

Results: Surprisingly, we could not confirm any of the suspected differential diagnoses. Instead, we detected cellular connective tissue with lymphoplasma cellular and monocytic infiltrates, suggested as being reactive. Since no S-100 expression could be verified, the findings were not conclusive for the presence of histiocytosis. Further immunohistochemical investigations revealed several CD163-positive cells as well as a few plasma cells expressing Ig-kappa and Ig-lambda chains equally. Since there was also no evidence of a meningioma, the histopathological results were attributed to the morphogenetic region of the inflammatory pseudotumor.

Conclusion: Although spinal inflammatory pseudotumors have a rare occurrence, we consider this disease as an important differential diagnosis in the tumor-like lesions of the spinal cord. This is because, as shown in earlier cases, the therapy requires the inclusion of glucocorticoids for a long period of time to prevent a rapid relapse and recurrent surgical treatments. As proven in our case, a therapy containing glucocorticoids can efficiently cure the inflammatory pseudotumor with a good outcome. However, the initial surgical treatment is still recommended to reduce the tumor mass and cure the spinal compression.