Natural History and Management of Incidentally Discovered Focal Brain Lesions Indeterminate for Tumor in Children.

Background: The incidental discovery of brain lesions in children has increased due to greater utilization of neuroimaging. Standardized surveillance and management guidelines following the discovery of such lesions remain nonexistent.

Objective: To study the natural history and management of incidental brain lesions in children.

Methods: A retrospective analysis of pediatric patients who were treated at our institution between 2000 and 2016 with incidentally detected brain lesions that were indeterminate for neoplasm on MRI.

Results: We identified 445 patients with incidental brain abnormalities of whom 144 had lesions indeterminate for neoplasm. Average age at diagnosis was 11.2 (SD = 4.14) yr and average follow-up was 3.8 yr (range 1-13.2 yr). Lesions showed no progression in 112 patients (77.8%), whereas progression was detected in 31 patients (21.5%). Mean time to progression was 32.3 months (SD = 24.4). A change in management was made in 13/144 patients (9%), which included surgical resection (n = 11), biopsy (n = 1), and lumbar puncture (n = 1). Lesion size, location, multiplicity, new-onset symptoms, associated contrast enhancement, or edema were not predictive of radiologic progression. Larger lesions and those with contrast enhancement or edema were significantly more likely to undergo surgery (P < .001 each). Median geometric diameter of lesions that did not undergo surgery was 6.5 mm, whereas that of surgically resected lesions was 12.5 mm (P < .001).

Conclusion: Most incidental brain lesions indeterminate for neoplasm have an indolent, benign course. For asymptomatic patients with radiologically stable lesions, we recommend conservative management with MRI and clinical surveillance at 6, 12, 24, 36, and 60 mo after detection.