RADIATION TREATMENT PLANNING WITH 18F-FDG PET/CT IN HEAD AND NECK CANCERS

ABSTRACT
Aim: With the developments in radiotherapy techniques, a significant increase has been observed in the local-regional control rates in patients with head and neck cancer. In the current study we aimed to evaluate the usability of 18F-FDG PET/CT in radiotherapy planning of head and neck cancer.

Materials and Method: In this study, patients with locally advanced stage head and neck cancer whose radiotherapy planning was designed over 18F-FDG PET/CT and whose curative radio (-chemotherapy) decision was made in our clinic were evaluated.

Results: A total of 19 patients whose treatment planning was done over 18F-FDG PET/CT were included in this study. Treatment volumes and critical organ volumes were determined in accordance with the protocols after combining 18F-FDG PET/CT axial sections with planning CT axial sections. Concomitant chemotherapy was applied to patients with an indication. Gross tumor volume (GTV), clinical tumor volume (CTV), planning tumor volume (PTV) and critical organ doses were evaluated using dose-volume histograms. It was observed that critical organ doses were not exceeded in all patients who were planned to be treated by fusion with 18F-FDG PET/CT, the doses planned to be applied to the target volumes were administered as planned, and no dose reduction was made in any patient.

Conclusion: This study confirms that in patients with locally advanced head and neck cancer, 18F-FDG PET/CT can be used reliably in determining the localization of primary tumors and lymph nodes, as well as in the administration of planned radiotherapy doses. It is thought that determining the treatment plans reliably will have a positive effect on long-term side effects and survival outcomes.

Key words: 18F-FDG PET/BT, Radiotherapy, Locally Advanced Head and Neck Cancer