HGG-47. DECREASED GROWTH VELOCITY WITH LONG TERM USE OF BRAFV600e AND MEK INHIBITION IN A PATIENT WITH ANAPLASTIC GANGLIOGLIOMA

PURPOSE: To describe decreased growth velocity with long term use of BRAFV600e and MEK inhibition in a patient with anaplastic ganglioglioma. RESULTS: 4-year-old patient was found to have a 6 x 4.6 x 5 cm mass in the hypothalamus. Pathology consistent with anaplastic ganglioglioma and chromosomal microarray revealed a BRAFV600e mutation. Patient started on dabrafenib and trametinib and tumor decreased 85% after 3 months. She is stable without significant toxicities 39 months on therapy, and is now 8 years old. Patient had been growing at the 25% for weight and 12% for height but is now 65% for weight and 0.5% for height. It is difficult to tease out the relationship between the tumor, the location of the tumor, and the BRAF and MEK inhibitors and their effect on growth. Discussions with the family and endocrinology are ongoing but being <1% for height will lead to decrease in quality of life. CONCLUSIONS: Further follow-up study is needed to determine if this is truly a long-term toxicity, or if this may just be a direct result of the location of the tumor. Would supplementation with growth hormone in this patient lead to losing control of a high grade tumor, or would it simply replace a hormone that is not produced?