Hybrid PET-MRI for Improved Tumour Diagnosis
Hybrid PET-MRI examination of a patient with a brain tumour. After surgery and radiotherapy, no tumour can be detected by MRI (left). The PET image (centre) shows an accumulation of FET, which points to new tumour growth (yellow area). The blood supply (MR-PWI) is not increased (right).Source: Forschungszentrum Jülich
Patients suffering from brain tumours benefit particularly from state-of-the-art hybrid devices that combine positron emission tomography (PET) and magnetic resonance imaging (MRI). These hybrid devices provide information on numerous aspects of the disease in a single examination. This has been shown in a study recently published in the Journal of Nuclear Medicine.
In the article, JARA-BRAIN scientists at Forschungszentrum Jülich compare the PET results obtained using a radioactively labelled amino acid (FET-PET) with those obtained by magnetic resonance perfusion-weighted imaging (MR-PWI). This imaging technique depicts the blood supply to the tumour.
The artificial amino acid labelled with fluorine-18 (18F fluoroethyltyrosine, FET) was developed at Jülich and has been successfully used for more than ten years for diagnosing brain tumours with positron emission tomography (FET-PET). The size and position of the tumour and the effects of treatment can be more effectively determined with FET-PET than with MRI alone. In past years, more than 2,500 patients have been examined as part of studies using FET-PET and have benefited from the diagnosis at Jülich.
In the current study, Dr. Christian P. Filss from the Institute of Neuroscience and Medicine and his colleagues examined a total of 64 patients using a modern hybrid PET-MRI scanner developed at Forschungszentrum Jülich in collaboration with Siemens. The device enabled the scientists to simultaneously determine the accumulation of amino acid FET using PET and the blood supply to the tumour by means of MR-PWI.
The study shows that in the case of gliomas FET positron emission tomography provides more precise information on the size and position of this type of brain tumour than MR-PWI. The scientists therefore came to the conclusion that this procedure should not be used as a replacement but rather as a complementary diagnostic method, ideally in a hybrid scanner.
In addition to researchers from Jülich, the present study also involved scientists from the university hospitals in Aachen, Düsseldorf, and Cologne.