The clinical trial “18F-FDG PET/CT versus conventional imaging in staging or primary muscle invasive bladder cancer”

Accurate pre-operative and post-operative tumour staging in most cancers is of essential importance for decision-making and prognostic classification. Imaging tools such as ultrasound, CT and MRI, have been developed in the past and introduced in the clinic without being compared to previously applied modalities as is being done for treatment modalities. Also newer versions of imaging machines which are more powerful than older versions are introduced over the years. FDG PET/CT has been demonstrated to have good sensitivity and specificity in the detection of metastatic disease in malignancies and provide additional diagnostic information that enhances clinical management more than CT or MRI alone. PET/CT is now widely used for tumour staging. In a number of malignancies it has been shown that PET/CT staging with FDG is significantly more accurate than PET alone, and side-by-side PET and CT.

In bladder cancer, relatively few imaging studies have been performed with FDG PET alone. The standard imaging work up worldwide includes PET/CT as diagnostic modality for the preoperative staging of muscle invasive bladder cancer next to CT although its extent of superiority compared to CT alone has not unequivocally been demonstrated in large contemporary series. In the present study diagnostic CT scans in combination with 18F-FDG PET/CT scans will be performed in all of the patients in order to quantify the added value of PET/CT imaging. The results of this large study will either result in evidence based level 1 evidence of current practice of using PET/CT in preoperative staging of patients considered for cystectomy (scientific assessment of level of evidence) or to omit PET/CT in the current standard work up policy of many centers (efficiency outcome and implications for health economics).