Retrospective Analysis of T2-Hyperintense Lesions in Children With Neurofibromatosis Type 1.

Objective: The aim of this study is to determine whether a previously reported three-tiered classification scheme for T2-hyperintense brain lesions in children with neurofibromatosis type 1 (NF1) was associated with distinct radiographic or clinical characteristics after 10 years of real-world follow-up data were obtained. Methods: In this single-center retrospective study, we analyzed T2-hyperintense lesions identified on brain magnetic resonance imaging (MRI) of 58 children with NF1. Lesions were categorized as "Low Likelihood of Tumor," "Intermediate Likelihood of Tumor," or "High Likelihood of Tumor" using predefined imaging criteria adopted by our institution. Clinical and radiologic data were evaluated with generalized estimating equations (GEEs). Results: No demographic variables were associated with lesion category, apart from small age differences and a lower proportion of "High Likelihood of Tumor" lesions occurring in males compared with "Low Likelihood of Tumor." Localization patterns differed modestly, but anatomic site was not associated with radiographic evolution or treatment. Most lesions initially classified as "Low Likelihood of Tumor" or "Intermediate Likelihood of Tumor" remained stable or resolved, and none required therapy. Even among lesions initially classified as "High Likelihood of Tumor," only a small subset required treatment, most often those demonstrating pronounced T1 hypointensity. Interpretation: NF1-associated T2-hyperintense lesions demonstrate substantial overlap in clinical and radiographic characteristics, particularly those classified as "Low Likelihood of Tumor" and "Intermediate Likelihood of Tumor," while generally following a benign course. Features such as lesion location, enhancement, or mass effect are not consistently associated with treatment. These findings support close monitoring of lesions classified as "High Likelihood of Tumor" with pronounced T1 hypointensity.