Head and neck cancers, particularly oral cavity malignancies, present unique diagnostic and therapeutic challenges due to their complex anatomy, variable patterns of spread, and the need to balance oncologic control with functional preservation. Positron Emission Tomography–Computed Tomography (PET-CT) fusion imaging has emerged as a pivotal modality in the oncologic imaging of oral cancer, integrating metabolic information with high-resolution anatomic detail to enhance clinical decision-making across the disease continuum.

PET-CT, most commonly using 18F-fluorodeoxyglucose (FDG), enables sensitive detection of primary tumors, regional nodal metastases, and distant disease, often surpassing conventional imaging in identifying occult lesions. Fusion imaging improves tumor delineation in anatomically complex regions, aids in accurate staging, and refines risk stratification, directly influencing treatment planning. In oral cancer, PET-CT plays a critical role in assessing depth of invasion, nodal burden, and extracapsular spread, which are key prognostic indicators. Furthermore, PET-CT has demonstrated significant value in radiation therapy planning by enabling biologically guided target volume definition, potentially reducing treatment-related morbidity.

Beyond initial staging, PET-CT is increasingly integral to response assessment and post-treatment surveillance, allowing early differentiation between residual or recurrent disease and post-therapeutic changes. Emerging applications, including quantitative metabolic parameters, radiomics, and integration with artificial intelligence, hold promise for personalized oncologic imaging and outcome prediction.

This keynote will highlight the current evidence, clinical impact, limitations, and future directions of PET-CT fusion imaging in oral cancer, emphasizing its role in multidisciplinary care and precision oncology. As imaging continues to evolve from purely diagnostic to decisional and prognostic, PET-CT stands at the forefront of transforming head and neck cancer management.