WholeBbody Positron-Emission-Tomography (WB-PET) in oncology

The new generation of high sensitive PET-Scanners with an FOV of about 15 cm allows to recognize with high sensitivity and good spezificity malign tumors and their metastases with 18F-FDG in a Whole-Body-Scan in 35 to 50 min scan time. 357 FDG-WB-PET-Scans have been performed in Tuebingen during 1 1/2 years since January 1994 in tumor patients and have been compared and evaluated to the results of other imaging methods performed in the same time together with clinics and in follow-up. In 4 groups of tumors - Melanoma - malign Lymphoma -Breast Cancer - Thyroid Cancer - and a fifth group of 24 various types of malign tumors we found a sensitivity of 88%, a specificity of 80% and an accuracy of 90%. Foci smaller than 6-8 mm diametre - mostly lung metastases or lymphomas - and also tumors of low malignancy such as 131l-trapping Tyroid Carcinomas and Ganglioneuroblastomas have been found false negative. Flase positive we found inflammated lymph nodes, abscesses and also benign thyroid adenomas. This high sensitivity makes 18F-FDG-WB-PET an important method for tumor searching and diagnosis of tumor spreading, esp. for primary and secondary staging in the future, but also as the unique imaging method which allows determination of resting tumor vitality after therapy. Further multi-center studies will be necessary before this method can be introduced to routine, that also is limited by the high costs of the procedure. (orig.)