Intraspinal epidermoid cyst successfully treated with radiotherapy: case report

Epidermoid cysts are benign lesions that account for 0.7% of all intraspinal tumors. Standard treatment is complete resection. The recurrence rate after surgery cannot be estimated from the scarce literature, but it has been acknowledged that, in some patients, curative surgery may be impossible and temporary relief of symptoms is the only aim.

In 1996, a 59-year-old woman presented with a 30-year history of a spinal epidermoid cyst, for which she had previously undergone eight operations. Spastic paraplegia of the lower limbs had been present from initial diagnosis, and the neurological level had moved upward to C6. At the time of presentation, paresthesia in her arms and hands had developed. A magnetic resonance imaging scan revealed typical sequelae of previous surgery and a fibrotic region starting at the level of C5-C6 with formation of a cyst that extended to the conus terminalis. The spinal cord could not be visualized caudally at C7.

Because both patient and surgeons did not want further surgical interventions that might comprise upper limb function, radiotherapy was performed. A dose of 46 Gy was delivered to the cervicothoracic spine (C4-T1) by opposing anteroposterior high-energy photon beams. The treatment was well tolerated, and after treatment, the patient's clinical symptoms improved slightly, without evolution on magnetic resonance imaging.

Irradiation was effective in stabilizing the patient's disease. Although radiotherapy is not established in the treatment of epidermoid cysts, it should be considered as an alternative to palliative surgery and in patients who cannot undergo operations.