Early disc degeneration in radiotherapy-treated childhood brain tumor survivors.

BACKGROUND: Childhood brain tumor (BT) survivors have an increased risk of treatment-related late effects, which can reduce health-related quality of life and increase morbidity. This study aimed to investigate lumbar disc degeneration in magnetic resonance imaging (MRI) in adult survivors of radiotherapy-treated childhood BT compared to age and sex-matched population controls. METHODS: In this cross-sectional comparative study, 127 survivors were identified from hospital registries. After a mean follow-up of 20.7 years (range 5-33.1), 67 survivors (mean age 28.4, range 16.2-43.5) were investigated with MRI and compared to 75 sex-matched population-based controls. Evaluated MRI phenotypes included Pfirrmann grading, , intervertebral disc protrusions, extrusions, and high-intensity-zone-lesions (HIZ). Groups were also compared for known risk factors of lumbar intervertebral disc (IVD) degeneration. RESULTS: Childhood BT survivors had higher Pfirrmann grades than controls at all lumbar levels (all p < 0.001). Lumbar disc protrusions at L4-5 (p = 0.02) and extrusions at L3-4 (p = 0.04), L4-5 (p = 0.004), and L5-S1 (p = 0.01) were significantly more common in the BT group compared to the control. The survivor cohort also had significantly more HIZ-lesons than the controls (n=13 and n=1, p=0.003). Age at diagnosis was associated with lower degree of IVD degeneration (p < 0.01). Blood pressure correlated with IVD degeneration (P < 0.05). CONCLUSIONS: Signs of early disc degeneration related to tumor treatment can be seen in the IVDs of survivors. Disc degeneration was more severe in children treated in adolescence.

Epidemiological, clinical, and genetic characteristics of paediatric genetic white matter disorders in Northern Finland.

AIM: To examine the epidemiological, clinical, and genetic characteristics of paediatric patients with genetic white matter disorders (GWMDs) in Northern Finland. METHOD: A longitudinal population-based cohort study was conducted in the tertiary catchment area of Oulu University Hospital from 1990 to 2019. Patients were identified retrospectively by International Statistical Classification of Diseases and Related Health Problems codes in hospital records and prospectively by attending physicians. Inclusion criteria were children younger than 18 years with defined GWMDs or genetic disorders associated with white matter abnormalities (WMAs) on brain magnetic resonance imaging. RESULTS: Eighty patients (mean age [SD] at the end of the study 11y [8y 6mo], range 0-35y; 45 males, 35 females) were diagnosed with a defined GWMD. The cumulative childhood incidence was 30 per 100 000 live births. Regarding those patients with 49 distinct GWMDs, 20% had classic leukodystrophies and 80% had genetic leukoencephalopathies. The most common leukodystrophies were cerebral adrenoleukodystrophy, Krabbe disease, and Salla disease. Additionally, 29 patients (36%) had genetic aetiologies not previously associated with brain WMAs or they had recently characterised GWMDs, including SAMD9L- and NHLRC2-related neurological disorders. Aetiology was mitochondrial in 21% of patients. The most common clinical findings were motor developmental delay, intellectual disability, hypotonia, and spasticity. INTERPRETATION: The cumulative childhood incidence of childhood-onset GWMDs was higher than previously described. Comprehensive epidemiological and natural history data are needed before future clinical trials are undertaken. What this paper adds Forty-nine distinct genetic white matter disorders (GWMDs) were identified, with 20% of cases being classic leukodystrophies. The cumulative childhood incidence of GWMDs was higher than described previously. A considerable proportion (36%) of GWMDs were previously undefined or recently characterised GWMDs. Mitochondrial aetiology was more common (21%) than previously reported.

Radiation-Induced Meningiomas After Childhood Brain Tumor: A Magnetic Resonance Imaging Screening Study.

Purpose: Childhood brain tumors (CBTs) and their treatment increase the risk of secondary neoplasms (SNs). We studied the incidence of secondary craniospinal tumors with magnetic resonance imaging (MRI) screening in a national cohort of survivors of CBT treated with radiotherapy, and we analyzed the Finnish Cancer Registry (FCR) data on SNs in survivors of CBT with radiotherapy registered as a part of the primary tumor treatment. Methods: A total of 73 survivors of CBT participated in the MRI study (mean follow-up of 19 ± 6.2 years). The incidence of SNs in a cohort of CBT patients (N = 569) was retrieved from the FCR (mean follow-up of 11 ± 12.9 years). Brain tumors were diagnosed at age ≤16 years between the years 1970 and 2008 in the clinical study and the years 1963 and 2010 in the FCR population. Results: Secondary brain tumors, meningiomas in all and schwannoma in one, were found in 6 of the 73 (8.2%) survivors with a mean of 23 ± 4.3 years after the diagnosis of the primary tumor. The cumulative incidence was 10.2% (95% confidence interval [CI] 3.9-25.1) in 25 years of follow-up. In the FCR data, the 25-year cumulative incidence of SNs was 2.4% (95% CI 1.3-4.1); only two brain tumors, no meningiomas, were registered. Conclusion: Survivors of CBT treated with radiotherapy have a high incidence of meningiomas, which are rarely registered in the FCR.