LG-59: MORTALITY IN CHILDREN WITH LOW-GRADE GLIOMA: A SINGLE-INSTITUTION STUDY

PURPOSE: Few studies address cause of death in children with low-grade glioma (LGG). METHODS: We conducted a retrospective review of clinical, pathologic, and radiologic data from children (<21 years old) with LGG who died, at St. Jude Children's Research Hospital between 1983 and 2015. RESULTS: For the 86 eligible patients, median age of diagnosis was 7.6 years (range, 0.1-21 years), median age of death was 14 years (range, 0.6-32 years), and median duration to death from diagnosis was 3.5 years (range, 0.2-32 years). Thalamus/midbrain was the most common tumor location (n = 35), followed by suprasellar/hypothalamic (n = 19) and hemispherical (n = 13). Astrocytoma, not otherwise specified (n = 23) was the most common histologic diagnosis, followed by pilocytic astrocytoma (n = 22), fibrillary astrocytoma (n = 12), and pleomorphic xanthoastrocytoma (n = 6). The cause of death was progression (PD) of primary tumor (n = 40), malignant transformation (MT) to a high- grade tumor (n = 17), sepsis (n = 4), second cancer (n = 3), suicide (n = 2), accident (n = 2), respiratory compromise (n = 4), and miscellaneous causes (n = 6). Cause of death was unknown in 8 patients. Among those with MT, 8/17 had received radiotherapy prior to transformation. Three patients had a diagnosis of neurofibromatosis type 1, 2 of whom died from a second malignancy and 1 from MT. Four patients had metastatic disease at diagnosis, and 29 developed metastasis during the clinical course. CONCLUSIONS: PD and MT contributed to 66% of the mortality in our patient cohort. Understanding the molecular basis of PD and MT is vital to plan optimal therapy for children with LGG and reduce mortality.