Chronic progressive radiation myelopathy (CPRM) is a clinical syndrome that manifests with spinal cord signs and symptoms. These can be severe and result in pain, paraesthesia, sensory deficits, paralysis, Brown-Sequard syndrome, and bowel/bladder incontinence.r
CPRM is an uncommon development, but usually occurs when portions of the spinal cord are included in radiotherapy treatment fields. This may occur when treating malignancies in the thoracic region, head and neck, abdomen and pelvis.
CPRM is a serious late effect of radiation treatment and can occur 6-24 months following RT.r
The estimated cumulative risks of CPRM have been reported between 0.5 to 10%. The risk of CPRM is related to the total dose of radiation delivered to the spinal cord. When conventional fractionation is used at doses of 1.8 to 2 Gy per fraction to the full thickness cord, the estimated risk of myelopathy is less than 1% for doses of up to 54 Gy. For doses of up to 61 Gy, the estimated risk is less than 10%. There is also a strong correlation between increased risk and dose per fraction.r