Lymph node staging for urinary bladder carcinoma with positron emission tomography (PET)

PET is a new method in nuclear medicine which examines the metabolism and n ot the morphology. Tumors show a higher rate of glycolysis than benign tiss ue and hence can be detected by radioactive glucose. This method has proved good for various tumors. In this study the lymph node staging of bladder c ancer by PET was investigated. In 64 patients a PET of the pelvis after inj ection of fluorodeoxyglucose (FDG) was carried out preoperatively; the PET- results were compared with the histology of the OR specimen after classical pelvic lymphadenectomy. For lymph node staging positive nodes were found i n 14 patients which was correct; a false-negative result was obtained in 7 patients. In 37 patients the PET-result was true-negative and in 6 patients false-positive resulting in a sensitivity of 67 %, a specificity of 86 % a nd an accuracy of 80 %. Therefore, our PET results are encouraging and seem to be better than those obtained by classical staging procedures such as C T or MRI.