Proton therapy for tumors of the base of the skull

Relative to conventional photon irradiation, proton therapy has distinct advantages in its ability to more precisely target tumor while shielding adjacent normal tissues. In the setting of skull base tumors, proton therapy plays a critical role in the dose-escalation required for optimal tumor control of chordomas, chondrosarcomas, and malignancies of the paranasal sinuses and nasal cavity. For benign tumors such as craniopharyngiomas, pituitary adenomas and meningiomas, proton therapy can limit long-term adverse effects, such as secondary malignancies. This review summarizes published literature to date regarding the role of proton therapy in skull base tumors and introduces emerging proton therapy approaches such as pencil-beam scanning (PBS).