Do you use bite block during radiation treatment for base of tongue (BOT) cancer?

Yes, we use intra-oral immobilization for any tongue (or BOT) involvement.

Japanese data suggest improvements in immobilization lead to clinically meaningful PTV implications (Doi et al., PMID 28515675) in head and neck cancers. Our in-house data suggests not having a stent on a BOT target requires a 2-3 mm extra PTV margin, but this is patient-specific w/r/t tumor location/extension.

Our internal data suggest that stent use (likely due to the displacement of the maxillary/buccal mucosa away from CTV/PTV, similar to what we see for tonsil (https://www.sciencedirect.com/science/article/pii/S2452109420302189) is associated with reduced toxicity in oropharyngeal cancers (Stieb et al., PMID 32642562) since we'd used stents for *all* oral cavity ...