Essentials for early diagnosis of primary intramedullary spinal cord lymphoma. How to suspect primary intramedullary spinal cord lymphoma early and proceed to invasive biopsy? A case report and literature review.

BACKGROUND: Primary intramedullary spinal cord lymphoma (PISCL) is an extremely rare condition. Early diagnosis is very difficult due to the nonspecific clinical and imaging findings. A biopsy is essential for a definitive diagnosis, but courage is required to perform the surgery. Here, we present a case of PISCL and suggest useful indicators for accurate diagnosis of this pathological entity.

CASE DESCRIPTION: A 70-year-old woman presented with subacute bilateral lower-limb paralysis, disturbance of warm and pain sensations, and vesicorectal disturbance. Magnetic resonance imaging showed a contrast-enhanced mass from C7 to Th2 and large, edematous lesions from the upper cervical to lower thoracic spinal cord. Elevated uptake of 18 F-fluoro-2-deoxy-D-glucose (FDG) was identified in the enhanced regions on FDG-positron emission tomography (PET). Cerebrospinal fluid (CSF) analysis revealed highly elevated levels of β2-microglobulin (β2-MG). Steroid pulse therapy and therapeutic plasma exchange were performed for suspected myelitis, but symptoms did not improve. Spinal cord biopsy was, therefore, performed for treatment-resistant myelopathy. Histopathological examination revealed diffuse large B-cell lymphoma, which was diagnosed as PISCL because systemic examination showed no other findings suggestive of malignant lymphoma.

CONCLUSION: In cases with poor response to treatment and a progressive course, PISCL should be considered, and spinal cord biopsy should be performed if PET shows increased 18 F-FDG uptake and β2-MG is elevated in CSF.