Neurologic Toxicity in Children with Acute Lymphoblastic Leukemia

Objective: The objective of this study was to evaluate the occurence of neurological complications and long-term neurological sequelae in children with acute lymphoblastic leukemia (ALL). These complications were examined in relation to demographic characteristics, leukemia risk groups, and chemotherapy type. Material and Methods: A total of 165 patients aged between 1 and 18 years of age who underwent ALL IC-BFM 2009 chemotherapy at the Pediatric Hematology Unit of Ankara Pediatric Hematology and Oncology Research and Training Hospital between June 2013 and December 2018 were retrospectively evaluated. Results: Forty-two neurological complication episodes (1 to 3 per patient) were observed in 37 (22.4%) patients during chemotherapy. No significant differences between groups with or without neurological complications were detected in terms of age, gender, type of leukemia, risk group assignment, and relapse status (p=0.150, p= 0.170, p= 0.810, p= 0.370, and p=0.340, respectively). Complications were more likely to occur in preB-ALL patients with intermediate to high-risk status, and approximately half of the complications were identified during the early phases of treatment, i.e., induction and early consolidation; also, vincristine, methotrexate, and corticosteroids were more likely to lead to neurotoxicity. The two most common complications included polyneuropathy in 47.6% of the patients and posterior reversible encephalopathy syndrome in 16.7%. Other complications included cranial neuropathy, secondary intracranial hypertension, cortical atrophy, epilepsy, encephalopathy, myopathy, cranial thrombosis, psychotic disorder, and cerebral edema. While none of the neurological complications were associated with mortality, 21.4% of the patients had varying types of sequela, the most common being epilepsy. Conclusion: Despite increased success rates with intense therapeutic approaches in pediatric ALL patients, 22.4% of this population experienced neurological complications. Long-term follow-up is warranted to evaluate the adverse effects and sequelae of chemotherapy more definitely.