Stellenwert der PET bzw: PET/CT mit F-18-FDG beim kleinzelligen lungenkarzinom

To date, most of the (relatively few) clinical studies that have ascertained the role of fluorodeoxyglucose positron emission tomography (FDG-PET) or PET/computed tomography (CT) in small cell lung cancer have been directed at differentiating limited from extensive disease and thus at exploring the therapeutic impact. It has been shown that the addition of PET in the staging algorithm correctly upstaged up to 33% of patients from limited disease to extensive disease compared with conventional diagnostic procedures alone. PET was especially more sensitive for detecting distant metastases. This way, (unnecessary) radiotherapy or surgery could be avoided. Patients suspected of having distant metastases were correctly downstaged by PET/CT and thus could undergo potentially curative therapy. Also, for radiation therapy planning, PET is valuable because it was found to be more sensitive and specific for detecting lymph node metastases than morphologic imaging procedures. The aforementioned, still relatively small, studies proved that FDG-PET is more sensitive for the detection of skeletal metastases; therefore, skeletal scintigraphy and bone marrow biopsy can be abandoned. However, for detection of brain metastases, magnetic resonance imaging (or CT) was found to be indispensable. Further studies are needed to find out whether FDG PET/CT will be able to replace other specifically invasive diagnostic methods and to determine the clinical relevance of PET/CT for detecting residual disease and for restaging patients.