Topographic metabolic map of head and neck squamous cell carcinoma using 18F-FDG PET and CT image fusion.

Objective To propose a methodologic approach to evaluate head and neck tumors in order to identify and distinguish areas of higher metabolic activity inside the lesion. Study design The sample consisted of 17 patients with squamous cell carcinoma of the head and neck. Images were simultaneously acquired using a nondedicated PET-CT device and an independent workstation with ENTEGRA 2 NT software to generate the image fusion between PET and CT. Sites of higher metabolic activity inside the tumor were classified as centric or eccentric according to their relative location to the lesion center. Results Seventy-seven percent (n = 13) of the patients presented the site of higher metabolic activity at the center of lesion, and in 23% (n = 4) the uptake of the tracer was increased at the periphery of the lesion. Conclusions This technique gave a realistic view of the functional metabolism, locating the anatomical tumor area and helping in future treatment planning.