Childhood Leukemia, Brain Tumor Survivors Risk Stroke
Cranial radiation therapy dose linked to stroke risk
WEDNESDAY, Nov. 22 (HealthDay News) -- Long-term childhood leukemia or brain tumor survivors have a sixfold to 29-fold higher risk of stroke later in life than their cancer-free siblings, researchers report in the Nov. 20 issue of the Journal of Clinical Oncology.
Daniel C. Bowers, M.D., of the University of Texas Southwestern Medical Center at Dallas, and colleagues compared the incidence of late-occurring strokes reported by 1,871 long-term brain tumor survivors, 4,828 leukemia survivors, and 3,846 cancer-free siblings. Sixty-three brain tumor survivors and 37 leukemia survivors had strokes.
Leukemia survivors had a higher relative risk of stroke (RR, 6.4) than cancer-free siblings, for a stroke rate of 57.9 per 100,000 person-years. Brain tumor survivors had a late stroke rate of 267.6 per 100,000 person-years, for a 29.0 relative risk of stroke versus cancer-free siblings. Higher stroke risk in brain tumor and leukemia survivors was associated with a 30 Gy or higher mean cranial radiation therapy dose, the greatest risk occurring in 50 Gy doses or higher.
"Survivors of childhood leukemia and brain tumors, particularly those with brain tumors treated with cranial radiation therapy at doses of greater than 30 Gy, are at an increased risk of stroke," the authors conclude.