Tumour imaging with F18-fluorodeoxyglucose (18F-FDG) has yielded promising results for the detection of a variety of tumours. Owing to the high costs and limited availability of dedicated Positron emission tomography (PET) scanners, alternative methods of imaging the 511-KeV photons of positron emitters have been sought. With a dual head coincidence camera PET scanning of FDG is possible. The system parameters, such as sensitivity and spatial resolution, are already measured, but the clinical experience of this alternative imaging method is very limited. Two cases are described in which tumours with a diameter of 4 and 5 mm, respectively, were detected using a dual head coincidence camera. The presented cases support the use of this converted gamma camera in head and neck oncology.