Performance of fluoro-2-deoxy-D-glucose positron emission tomography-computed tomography imaging for lymph node staging in bladder and upper tract urothelial carcinoma: a systematic review

Objective: To evaluate the current literature on the accuracy of fluoro-2-deoxy-D-glucose positron emission tomography-computed tomography (FDG PET-CT) for lymph node (LN) staging in urothelial carcinoma (UC), as robust evidence on the value of this technology in UC is still lacking. Methods: The Medical Literature Analysis and Retrieval System Online (MEDLINE)/PubMed, Cochrane Library, and Scopus databases were searched for eligible studies. We included all original studies evaluating FDG PET-CT in bladder or upper tract UC. The search results were restricted to the English language, and included prospective and retrospective studies without time restriction. We included only studies reporting the sensitivity and specificity of FDG PET-CT in detecting UC LN metastases. Results: We identified 23 articles meeting our inclusion criteria. In the preoperative setting, the sensitivity of FDG PET-CT for detecting LN metastases in patients with bladder cancer was widely variable ranging from 23% to 89%; the specificity ranged from 81% to 100%; and the overall accuracy ranged from 65% to 89%. During bladder cancer monitoring the sensitivity for detecting LN metastases ranged from 75% to 92% and the specificity ranged from 60% to 92%. The sensitivity for LN staging in upper tract UC ranged between 82% and 95%, with a specificity of 84–91%. Conclusion: Despite the inconsistencies in sensitivity between the reports, FDG PET-CT seems to have a high specificity for LN staging in patients with UC. Future prospective, well-designed studies are necessary to evaluate the role of FDG PET-CT in UC management. Abbreviations: FDG: fluoro-2-deoxy-D-glucose; LN: lymph node; PET: positron emission tomography; PRISMA: Preferred Reporting Items for Systematic Reviews and Meta-analyses; PSMA: prostate-specific membrane antigen; (N)(P)PV: (negative) (positive) predictive value; QUADAS-2: Quality Assessment of Diagnostic Accuracy Studies-2; SUV(max): maximum standard uptake value; (UT)UC: (upper urinary tract) urothelial carcinoma