Rapid and profound radiological and plasma ctDNA responses to dabrafenib plus trametinib in BRAF-mutant papillary craniopharyngioma

Abstract A 38-year-old male patient was diagnosed with a BRAF-V600E mutant papillary craniopharyngioma. Due to the neurological and endocrine sequalae from multiple surgeries, irradiation of residual tumor was disregarded. Dabrafenib plus trametinib treatment was started achieving a rapid neurological improvement and a profound radiological response (-92%) still ongoing 9 months later, despite treatment withdrawal after 7.5 months of therapy due to toxicity (grade 3 pyrexia). In parallel, BRAF-V600E mutation ctDNA monitoring in plasma showed a profound and durable response. Additional therapeutic trials evaluating upfront BRAF-targeted therapy to minimize local therapies (including surgery and radiation) are needed. Liquid biopsy should be further explored as a non-invasive way of diagnosis and treatment monitoring.