Exploring perspectives on skull base chordoma management: a modified Delphi approach to consensus

Current treatment for skull base chordomas utilizes both surgical resection and adjuvant radiation, but recent studies have demonstrated evidence that has brought the use of adjuvant radiotherapy into question. Chordomas differ greatly in molecular makeup and proliferation. These factors have led to significant variation in management across providers. We used a modified Delphi approach to work towards consensus on standardized operative definitions and evidence-based management of chordomas.

Our multidisciplinary panel included participants representing the AANS/CNS Tumor Section and North American Skull Base Society (NASBS) with a track record of publishing on chordoma management. Our approach involved a four-step process: one statement-generation round, two voting rounds to establish consensus and refine statements, and a final external validation round by NASBS members. Anonymous voting was completed via Qualtrics surveys.

The statement-generation process produced 65 statements. Through the Delphi process, 36 statements reached consensus during the first round and an additional 17 were refined for further consensus in the second round. Moderate (67-80%) or strong (> 80%) consensus was achieved for 43 final statements. Forty-one items were externally validated. There was consensus that an endoscopic endonasal approach should be utilized whenever possible. They defined the tumor characteristics (molecular and cytogenic) to consider before offering adjuvant radiotherapy.

This modified Delphi study generated consensus on 41 statements regarding skull base chordoma management. These statements aim to shed light on the consensus among providers regarding the use of surgery, neoadjuvant radiation, adjuvant radiation, adjuvant systemic therapies, and treatment of recurrence for chordoma.