Intravascular Lymphoma Presenting with Cauda Equina Syndrome: Treated with CHOP and Rituxan

An 86-year-old man presented in October of 2001 with sudden loss of bowel and bladder control accompanied by bilateral lower extremity weakness and radicular pain. His past medical history was significant for an aortic valve replacement at age 80 followed 2 years later by the onset of chronic atrial fibrillation and intermittent lower extremity edema. Subsequently the patient underwent placement of a dual chamber pacemaker. In the 12 months prior to presentation the patient had noted an increased frequency of fatigue in the legs with intermittent cramping, weakness and burning pains. ABIs, lower extremity dopplers, echo, abdominal CT and labs were all unremarkable. The patient reported that in the weeks prior to presentation his sensation of fatigue in the lower extremities was significantly increased. He found that walking more than 100 yards required rest. On the evening of presentation the patient was awakened from sleep by severe shooting pains in both lower extremities. He attempted to ambulate but collapsed due to weakness and found that he was unable to maintain fecal or urinary continence. Physical exam revealed 1/5 lower ext weakness and decreased reflexes. Laboratory results at that time demonstrated a WBC of 6.2, Hb of 12.2 and platelets of 138. All of these results were commensurate with routine lab work from the prior year. A lumbar spine CT scan demonstrated only mild to moderate spinal stenosis. CT of the head, chest abdomen and pelvis were unremarkable. Myelogram confirmed the finding of mild spinal stenosis. There was no evidence of cord compression or vertebral fracture. Subsequent nerve conduction studies and EMG were consistent with acute denervation and changes consistent with demyelinating disease. Nerve biopsy demonstrated moderate loss of myelinated fibers with rare degenerating fibers. Several endoneurial vessels showed marked basement membrane thickening and very rare large nucleated cells present within the lumina. Muscle biopsy demonstrated a few vessels with large nucleated discohesive cells which in some sections occluded the entire vessel (Fig. 1). Immunohistochemistry demonstrated strong reactivity for CD20, but not for CD3 or CD5 (Fig. 2). Bone marrow biopsy was normocellular with normal maturation. A diagnosis of intravascular lymphoma (IVL) was made. The patient underwent two cycles of CHOP therapy. Due to a transient decrease in ejection fraction by MUGA scan the patient subsequently received six more cycles of cytoxan, etoposide and prednisone. Subsequently, the patient was given 500 mg of rituxan every 2 weeks for a total of six doses. He had no complications. His strength improved to the point that he could ambulate with a walker. He required daily straight catheterization for urination and complained of intermittent anal leakage. Ten months following the initial diagnosis of IVL, the patient continues to slowly regain strength and improve in bowel continence. His atrial fibrillation resolved and ejection fraction has improved. Repeat CT evaluation at 8 months after diagnosis shows no focal indication of disease and CBC remains normal.