Objectives: To describe the clinical presentations, radiologic features, and postoperative outcomes of a clinic-based population of patients with subependymal giant cell tumors (SGCT) and tuberous sclerosis complex (TSC) and to redefine and reclassify SGCT based on radiologic, clinical, and pathologic criteria.
Methods: Of 134 TSC patients evaluated from December 2001 to November 2003, 11 (8.2%) had undergone resection of a pathologically confirmed SGCT. The authors reviewed the medical records of each case. Follow-up ranged from 2 months to 36 years.
Results: Four were asymptomatic at the time of resection while the other seven presented subacutely with fatigue, decreased appetite, headache, increased seizure frequency, visual field deficit, cognitive decline, or behavioral problems. Poor outcomes occurred in all patients aged 11 years or older at the time of resection.
Conclusions: Subependymal giant cell tumors in patients with TSC appear to be of mixed glioneuronal lineage, and, therefore, the current practice of classifying these tumors as astrocytomas merits revision. The clinical diagnosis of SGCT should be made for subependymal lesions in TSC that are associated with symptoms, papilledema, or radiologic evidence of hydrocephalus or interval growth. A diagnosis of probable SGCT should be made when a lesion has the potential to cause obstruction based on size or location. Annual screening by MRI with or without contrast is indicated until at least 21 years of age even if subependymal nodules are absent on initial imaging. A diagnosis of SGCT or probable SGCT warrants more frequent monitoring or surgical intervention.