High incidence of radiation-induced cavernous hemangioma in long-term survivors who underwent hematopoietic stem cell transplantation with radiation therapy during childhood or adolescence.

Radiation-induced cavernous hemangioma (RICH) is a late complication of cerebral radiation therapy. Long-term survivors of hematopoietic stem cell transplantation (HSCT) who underwent radiation therapy could be at increased risk for RICH. We investigated records of 68 patients who underwent HSCT during childhood or adolescence and were assessed by magnetic resonance imaging (MRI), including T2*-weighted imaging of the brain, annually for 5 years over a range of 6 to 29 years after HSCT. We developed a scoring and grading system for RICH to monitor the process and the progress of radiologic changes. Among the 68 patients investigated, 28 (41.2%) were diagnosed with CH. All 28 patients had received total body irradiation as a conditioning treatment for HSCT and/or cranial radiation therapy before HSCT as part of the treatment of their primary disease. RICH was diagnosed in none of the patients who did not receive radiation (n = 19), in 46.2% of those who received 6 to 12 Gy (n = 39), and in all of those who received 18 to 36 Gy (n = 10). Total RICH scores were correlated with higher radiation doses. Careful and long-term evaluation with MRI, including T2*-weighted imaging, is necessary for HSCT recipients who received radiation therapy before and/or during HSCT.