CNSC-79. Malignant (Non-Subependymal) Gliomas in Patients With Tuberous Sclerosis: Two Cases and a Literature Review

Tuberous sclerosis complex (TSC) is a genetic disorder resulting from mutations in the TSC1/TSC2 tumor suppressor genes. It causes benign tumors in multiple organs including the brain with cortical tubers, subependymal nodules, white matter abnormalities, and low-grade subependymal giant cell astrocytomas (SEGAs). Reported cases of malignant gliomas in TSC patients, with two new cases, are presented below. A 49-year-old woman, with TSC, cortical tubers, epilepsy, and taking everolimus for renal angiomyolipoma, presented with new headaches; a glioblastoma was resected. She underwent radiation, temozolomide, and bevacizumab. She is stable 12 months after diagnosis. A 57-year-old male, with a history of TSC, epilepsy, and cortical tubers, presented with new headaches. An enhancing brain mass was resected as a glioblastoma. He experienced mesenteric ischemia and bowel infarction and died three weeks later. A 22-month-old male, with a malignant gemistocytic astrocytoma, diagnosed after presenting with lethargy and vomiting, survived five months after surgery and radiotherapy. A 17-year-old male had upper motor neuron signs, from a glioblastoma, which was resected and radiated. A 26-year-old male developed glioblastoma eight years after radiation and excision of a SEGA. He died four months after surgery and chemotherapy. A 5-year-old male, with TSC2, lived three years following surgery, chemotherapy, radiotherapy, and mTOR inhibition for glioblastoma. A 33-year-old female presented with behavioral changes and hemiparesis; a glioblastoma was resected. A 58-year-old male, with confusion, dysphasia, and hemiparesis, had a glioblastoma and survived one month. An 11-month-old male had a SEGA resected which recurred as a malignant SEGA; he remained recurrence-free five years after chemotherapy. A 54-year-old male, with TSC1, developed visual loss secondary to a glioblastoma. He received surgery, radiotherapy, chemotherapy, bevacizumab, and anti-PD-L1 antibody, surviving 12 months post-surgery. These cases raise the question of whether malignant gliomas, in patients with TSC, may be more frequent and appear earlier.