ESTRO 2024 - Abstract Book

S1194

Clinical - Head & neck

ESTRO 2024

Conclusion:

This study reports the results of a 3-year single institution experience in buccal-alveolar complex carcinoma treatment focusing on finding relapse patterns. The prevalence of high-dose region failure suggests that innate radioresistance is a major factor in the recurrence of disease within the irradiated volume, rather than dose inhomogeneity or underdosing. Another common pattern of recurrence noted was extraneous disease in the non irradiated neck region. Contralateral neck nodal recurrence post bilateral elective nodal irradiation was on par with previous studies, suggesting that poor disease biology itself along with inaccurate risk assessment could be the driving factors. Reducing volumes from bilateral to unilateral neck did not seem to increase nodal failures. Conservative target volumes to avoid severe mucositis in the lip region, possible inadequate surgical bed clearance in preserving innate anatomy of lip-anterior commissure region, and can be hypothesized as a reason for the high incidence of anterior margin failures. This reinforces the use of more lenient treatment volumes covering the entire flap.

Keywords: Bucco-alveolar Complex Carcinoma, Failure pattern

References:

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