Case report

A 24-year-old male came to seek medical attention for three months history of low back pain associated with the burning sensation of bilateral lower limbs. For the last 12 days, he was unable to walk due to gradually progressive weakness in bilateral lower limbs. These symptoms were not accompanied by fever, headache, and night sweats. He could not recall any history of trauma in the past. His past medical and surgical history was not significant.
On examination, there was a localized tenderness over the thoracolumbar region. Lower limb motor power varied across muscle groups: hip flexors (2/5 bilaterally), knee extensors (2/5 bilaterally), ankle dorsiflexors (2/5 bilaterally), long toe extensors (3/5 bilaterally), and ankle plantar flexors (3/5 bilaterally). The sensation of lower limbs was altered bilaterally, but bowel and bladder habits were normal. Deep tendon reflexes in the knee and the ankle joints were absent. Plantar reflexes were downgoing bilaterally.
With the clinical diagnosis of a space-occupying lesion in the thoracolumbar spine region, an X-ray of dorsolumbar spine was done. Apart from the loss of lumbar lordosis, the rest of the X-ray findings were normal. Magnetic resonance imaging (MRI) of the thoracolumbar spine with screening of the whole spine revealed extradural lesion extending from T10 to L2 vertebral level. T1W image showed homogenous lesion which was iso to hypo-intense and the T2W image showed heterogeneous lesion which was iso to hyperintense, compressing over the spinal cord dorsally (Figure 1, 2). Sagittal short tau inversion recovery (STIR) image also revealed an extra-medullary lesion with high signal intensity to the vertebral marrow (Figure 3). Chest X-ray, complete blood count (CBC), liver and renal function tests, erythrocyte sedimentation rate (ESR), c-reactive protein (CRP), peripheral blood smear, lactate dehydrogenase (LDH), uric acid and urinalysis were normal. The diagnosis of the extradural tumor over the T10-L2 vertebrae was made.
Decompression (laminectomy) and excision biopsy of the mass was planned. The thoracolumbar spine (T9 to L3) was approached midline posteriorly. After laminectomy, a dorsally located greyish red extradural tumor extending from T10 to L2 was removed in strips. One of the long strips of the excised mass (approximately 15 x 1 cm) was sent for histopathological examination (Figure 4). Histopathology identified it as DLBCL (Figure 5). Immunohistochemistry analysis showed CD3-, CD20+, CD30+, CD10+, ALK-1-, BCL-6+, MUM-1- and Ki-67+. No other lesion was detected on staging evaluation which included contrast-enhanced computed tomography (CECT) of chest, abdomen, and pelvis, and bone marrow aspiration and biopsy.
His postoperative period was uneventful with successful recovery in his symptoms including neurology. He was referred to a cancer center after 16 days of hospital stay where he obtained six cycles of chemotherapy with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisolone (R-CHOP) regimen. After the treatment, the tumor regressed and he fully regained his muscle power. At the latest, one-year follow-up, he is asymptomatic and is performing his routine daily activity.