Fluorine-18-FDG detection of laryngeal cancer postradiotherapy using dual-head coincidence imaging.

Abstract

The aim of this study was to investigate whether, in patients treated for laryngeal carcinoma, a differentiation was possible between local recurrence or local control using a dual-head SPECT camera with PET capability. Eleven male patients (age range 51-71 yr; mean age 62 yr) who had previously undergone radiotherapy for laryngeal carcinoma were studied using 5 mCi (185 MBq) 18F-fluorodeoxyglucose (FDG). The mean interval between initial treatment and 18F-FDG PET was 21.9 mo (range 6-65 mo). Six patients had histologically proven local recurrence and five patients showed local control clinically. The mean follow-up in the local control group was 5.2 mo. Fluorine-18-FDG PET scans were positive in all six local relapses. Histopathological examination of the laryngectomy specimen revealed a mean tumor size of 2.6 cm (range 1.4-5.0 cm). In one patient, false-positive uptake was seen in an inflammatory lymph node. Fluorine-18-FDG PET scans were negative in all five patients with local control. It is possible to differentiate between local recurrence and local control in patients previously treated for laryngeal carcinoma with a dual-head SPECT scanner with PET capability.