Introduction: The extensive use of magnetic resonance imaging (MRI) has led to increased detection of incidental intracranial abnormalities. Optimal management of asymptomatic children with small, nonenhancing intracranial lesions, presumed to be low-grade gliomas (LGG) is not entirely clear in the literature. However, surgical intervention via resection or biopsy is not without risk and is of questionable long-term benefit in children. We describe our experience with non-surgical, conservative management of these incidental lesions in series of pediatric patients treated by a multidisciplinary team at a tertiary care center.

Methods: The authors retrospectively reviewed a series of eleven cases of children with T1 hypointense and T2 hyperintense intracranial lesions less than 2 cm without enhancement or surrounding edema. The subjects were all managed non-surgically with serial MRI studies and neurologic assessment by a neurosurgeon or neuro-oncologist.

Results: Eleven patients (8 male, 3 female) presented to neurosurgery clinic with intracranial lesions. Virtually all of the patients were asymptomatic. Most patients (n=5, 45.5%) received MRI studies after suffering a traumatic injury with evidence of an abnormality seen on computed tomography (CT) scan. Others received MRI scan as part of headache work-up (n=4, 36.4%). All lesions were T1 hypointense, T2 hyperintense, less than 2cm in size, non-enhancing, without significant surrounding edema. The majority of lesions were located infratentorially (n=8, 72.7%), while other locations included the frontal lobe and thalamus. The median age of the patients upon identification of intracranial abnormality was 11 years (range 9-19 years of age). No patient underwent surgery, radiation therapy or chemotherapy. Patients were followed for a median of 10.2 months (range 3-35 months). The most common diagnosis based on clinical and radiographic features of these lesions consisted of low-grade glioma. One patient also underwent advanced MR spectroscopy to support this diagnosis.

Conclusions: Our case series suggests that conservative management of incidental radiographic lesions consistent with LGGs is a safe and effective strategy in the pediatric population. Further studies that include a larger number of patients and longer follow-up period are required to compare outcomes between this approach and surgical, radiation, or chemotherapy management strategies.

Patient Care: The role of conservative management of incidental lesions consistent with LGGs in the pediatric population depends on multiple variables, including size, location, and change in imaging characteristics over time. Given the multiple factors involved, the lengthy natural history of the disease and the variable impact of interventions, it is unlikely that a randomized controlled clinical trial evaluating the role of conservative management of LGGs will take place. Our case series supports the role of conservative management in this particular population with emphasis on long-term follow up of these patients via a multidisciplinary team.

Learning Objectives: By the conclusion of this session, participants should be able to: 1) Describe the importance of recognizing the various treatment options aailable for peditric patients with low grade gliomas, 2) Discuss, in small groups, the risks and benefits of non-surgical, conservative management of low grade gliomas in pediatric patients, and 3) Recognize that conservative management of low grade gliomas in symptomatic pediatric patients is a safe and effective management strategy.

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