Case Diagnosis: Diffuse Large B cell Lymphoma /Conus Medullaris Syndrome
Diffuse Large B cell Lymphoma (DLBCL) has been previously demonstrated to affect the spinal cord through extramedullary (extradural and intradural) and rarely as intramedullary lesions (1). However, the evaluation of patients with spinal disorders can be complex and fraught with diagnostic pitfalls and astute clinical nous is necessary to identify lesions that masquerade as mechanical spine disease (2).
Case Description: 63 year old female with no past medical history presented with progressive bilateral lower extremity weakness, urine incontinence, and saddle anesthesia. Pre-operative lumbar magnetic resonance imaging (MRI) demonstrated degenerative lumbar scoliosis, increased T2 signal in the conus medullaris with only mild central stenosis at L4-5. Patient was incorrectly presumed to have cauda equina syndrome and underwent L3-L5 laminectomy. Post-operative course complicated by continued neurological decline prompting transfer to an academic medical center for further evaluation. Initial exam was notable for diffuse weakness in bilateral lower extremities, impaired lumbosacral sensation and partial surgical incision dehiscence. Repeat MRI of the lumbar spine demonstrated enlarging, heterogeneous T2 lesion involving the lower thoracic cord and conus medullaris and expected post-surgical changes. Given enlarging lesion in the conus, concern for malignancy prompted further diagnostic studies and confirmed metastatic DLBCL. Additionally, patient developed an enterococcus surgical site infection requiring transfer to a higher level of care.
Discussions: Unfortunately, the lack of accurate and timely diagnosis resulted in increased morbidity for this patient. Poor interpretation of advanced neuroimaging in conjunction with poor clinical judgment led to inaccurate diagnosis and unwarranted surgical treatment, respectively (3). This case demonstrates an unusual presentation of DLBCL.
Conclusions: It is important for interventional spine physicians to be aware of this clinical entity, diagnostic testing, and treatment in order to prevent increased morbidity.