A 67-year-old female presented with a low back pain and left sciatica. Although the patient had experienced occasional mild low back pain for several years, her low back pain markedly worsened 2 months before her first visit to our service. She also complained of newly developed left sciatica during this period, resulting in intermittent claudication. She had not noticed her urinary symptoms specifically, until she was asked at the examination, but she stated that those symptoms had started several months before her first visit. She denied any history of trauma, infectious diseases, or surgeries related to her spine. She had a history of several abdominal surgeries: cholecystectomy for gallstone and Hartmann’s procedure for rectal cancer 10 years ago and Miles’ surgery for anal cancer 9 years ago. She also had a mesh repair surgery for ventral hernia 5 years ago. All abdominal procedures were performed under general anesthesia with epidural anesthesia in her thoracolumbar spine. Radiographs of her lumbar spine showed some degenerative changes including decreased disc height and mild scoliotic changes. Magnetic resonance imaging (MRI) of her lumbar spine demonstrated an intradural extramedullary spinal cord tumor at the T12–L1 level (2.1 cm × 1.2 cm), and her spinal cord was markedly shifted anteriorly by the enlarged tumor. Computed tomography (CT) of her thoracolumbar spine did not show any calcification in the spinal canal. Because she had a history of contrast dye anaphylactic shock, a myelography was not performed. She also denied taking an MRI with contrast. Spinal dysraphism or skin abnormalities were not observed in her lumbar/sacral region. On her neurological examination, she showed full strength and an unremarkable sensory deficit in bilateral upper extremities. The patient showed motor weakness 4/5 in the left lower extremity (iliopsoas, hamstring, quadriceps, foot dorsiflexion, and plantar flexion). Decreased sensation in the left L1 to L3 (6/10) and the left L4 to S1 (8/10) distribution was observed. The right lower extremity demonstrated full strength, and her sensation was intact in the right lower extremity. Although sphincter tone was not diminished and perianal sensation was intact, she was found to have urinary symptoms, such as urinary frequency and a feeling of residual urine. Reflexes were normal in the upper extremities bilaterally; however, hyperreflexia was observed in the patellar reflex bilaterally. Babinski sign was negative bilaterally. Because her symptoms deteriorated, a surgical treatment was performed. A laminectomy from T12 to L1 was performed, and the local dura mater was incised in the midline until the tumor was exposed. The tumor excision was performed using microscopy. There was a mild adhesion between the tumor and the arachnoid membrane. Lumbar spinal nerve roots were not involved. Because there was some adherence between the tumor’s thin capsule and the conus medullaris, the capsule ruptured during resection. The spilled tumor contents were removed as well as the tumor itself. The thin capsule attached to the conus medullaris was also removed carefully. After the spinal canal was flushed by large amount of water, the dura mater and arachnoid membrane were sutured tightly. The surgical time was 151 min, and the estimated blood loss was 48 ml. Motor evoked potentials were used for neurological monitoring, and there was no alarm during the procedure. Histological examination of the specimens demonstrated that the cyst walls lined with stratified squamous keratinizing epithelium surrounded by the outer layer of collagenous tissue with the absence of skin adnexa. Abundant keratin material was also observed. A diagnosis of epidermoid cysts was confirmed. She could ambulate immediately postoperatively, and her left sciatica and leg weakness significantly improved 3 months after the surgery. Her MRI showed complete resection of the tumor, and there was no recurrence at 2-year follow-up.