Meningioma Screening With MRI in Childhood Leukemia Survivors Treated With Cranial Radiation.

Abstract

Radiation-induced meningioma is a known late effect of cranial radiation therapy. Cranial magnetic resonance imaging (MRI) can detect small meningiomas, but its potential value as a screening tool is unknown. MRI was used to screen asymptomatic survivors of childhood acute lymphoblastic leukemia (ALL) treated with cranial radiation therapy ≥10 years previously. The incidence of radiation-induced meningioma and outcomes of this group were compared with a historical cohort of survivors with the same exposure who underwent imaging only to investigate clinical signs or symptoms. One hundred seventy-six childhood leukemia survivors were included in this study: 70 in the screening group and 106 unscreened. Screening MRI was performed a median of 25 years after radiation therapy and detected meningioma in 15 (21.4%). In the unscreened group, 17 patients (16.0%) had neurologic symptoms leading to an MRI a median interval of 24 years after radiation therapy, 9 of whom (8.5%) were diagnosed with meningioma. There was no significant difference between screened versus unscreened patients in the size of meningioma (mean diameter, 1.6 cm vs 2.6 cm; P = .13), meningioma incidence (7.4% vs 4.0% at 25 years; P = .19), or extent of resection. Three patients had persistent neurologic symptoms in the unscreened group versus none among screened patients (P = .28). Screening MRI was able to detect small meningiomas that were not clinically apparent; however, we could not demonstrate a significant improvement in the chance of total resection or a significant decrease in morbidity. A larger sample could clarify potential reduction in neurologic sequelae associated with screening.