2025 Proffered Presentations
S009: NOVEL CLINICAL PATHWAY FOR DIAGNOSIS AND TREATMENT OF PAPILLARY CRANIOPHARYNGIOMAS
Amy J Wang; Lucas Martinez; Pamela Jones; Massachusetts General Hospital
OBJECTIVE: Craniopharyngiomas are locally invasive and often multiply recurrent tumors of the sellar/suprasellar region. Historically, the mainstay of treatment has been surgical decompression and resection, typically via open transcranial or endoscopic endonasal approaches. The papillary subtype of craniopharyngiomas frequently harbors a BRAF V600E mutation, rendering them amenable to targeted therapies. We present our institution’s initial experience and outcomes utilizing a less invasive endoscopic transventricular approach for biopsy, followed by medical treatment with targeted BRAF/MEK inhibitors if the biopsy determines a papillary subtype.
METHODS: We retrospectively reviewed five cases of patients with papillary craniopharyngiomas diagnosed via endoscopic transventricular biopsy between 07/2018 and 08/2023, who then underwent medical treatment with BRAF/MEK inhibitors. Patient characteristics, presenting symptoms, tumor volumes, and surgical outcomes were collected from the electronic medical record. Tumor volumes were collected from radiology reports.
RESULTS: The mean initial tumor volume was 23.8 cm3 (11.5 – 57.3 cm3, std 19.1 cm3). All patients underwent endoscopic transventricular tumor biopsy. The median length of stay was 1 day (range 1-5 d), and there were no surgical complications. Four patients were treated with Vemurafenib/Cobimetinib and one with Dabrafenib/Trametinib. Following treatment, at last follow-up (median 4.2 years, range 0.8 – 5.3 years), the mean tumor volume was 0.7 cm^3 (0.29 – 1.5 cm3, standard deviation 0.5 cm3) for a mean reduction of 96.9% (96.0 – 97.6%, std 0.7%). The most common side effects of BRAF/MEK inhibition were severe rash, followed by headache, fevers, nausea/vomiting; one patient developed transaminitis and another acute kidney injury. All patients received at least 1 cycle of treatment (median 5 cycles, range 1-5 cycles, one currently continues on therapy). Two patients underwent radiation after maximum tumor shrinkage was achieved following 5 cycles of therapy, with a total of 52.7 and 54 Gy.
CONCLUSION: When anatomically feasible, transventricular biopsy for tissue sampling of suspected PCPs is a safe and well tolerated surgery, allowing for an expedited pathway to dramatic and durable tumor shrinkage from BRAF/MEK inhibitors. Future directions include improved radio-diagnostics and possible “liquid biopsy” for BRAFV600E, which would support a pathway for neoadjuvant treatment with targeted therapy prior to surgery and/or radiation.