Purpose: Children with acute lymphoblastic leukemia (ALL) are often cured, but the therapies they receive may be neurotoxic. Little is known about the incidence and severity of late-occurring neurologic sequelae in ALL survivors. Data were analyzed to determine the incidence of adverse long-term neurologic outcomes and treatment-related risk factors.
Patients and methods: We analyzed adverse neurologic outcomes that occurred after diagnosis in 4,151 adult survivors of childhood ALL who participated in the Childhood Cancer Survivor Study (CCSS), a retrospective cohort of 5-year survivors of childhood cancer diagnosed between 1970 and 1986. A randomly selected cohort of the survivors' siblings served as a comparison group. Self-reported auditory-vestibular-visual sensory deficits, focal neurologic dysfunction, seizures, and serious headaches were assessed.
Results: The median age at outcome assessment was 20.2 years for survivors. The median follow-up time to death or last survey since ALL diagnosis was 14.1 years. Of the survivors, 64.5% received cranial radiation and 94% received intrathecal chemotherapy. Compared with the sibling cohort, survivors were at elevated risk for late-onset auditory-vestibular-visual sensory deficits (rate ratio [RR], 1.8; 95% CI, 1.5 to 2.2), coordination problems (RR, 4.1; 95% CI, 3.1 to 5.3), motor problems (RR, 5.0; 95% CI, 3.8 to 6.7), seizures (RR, 4.6; 95% CI, 3.4 to 6.2), and headaches (RR, 1.6; 95% CI, 1.4 to 1.7). In multivariable analysis, relapse was the most influential factor that increased risk of late neurologic complications.
Conclusion: Children treated with regimens that include cranial radiation for ALL and those who suffer a relapse are at increased risk for late-onset neurologic sequelae.