Mieke Bus

26 Chapter 2 Diagnostic work-up of UTUC The EAU guideline recommends performing a diagnostic URS including biopsy, urinary cytology, CT-urography and retrograde pyelography in patients with UTUC. 16 Most urolo- gists involved in the treatment of upper urinary tract tumours follow the guidelines in their diagnostic work-up of patients suspected for UTUC as showed in table 3. Current diagnostics have several limitations, withholding a safe patient selection for conservative treatment of UTUC. During URS, carcinoma in situ (CIS) is easily missed and histopathological diagnosis obtained during URS is often inconclusive due to the difficulties of tissue sampling hamper- ing adequate pathological diagnosis. 17,18 Additionally, cytology yields a low sensitivity and specificity and the diagnostic accuracy of CT urography decreases in case of small and/or flat lesions. 19-21 These facts underline the need for new diagnostic techniques in order to reliably select patients for endoscopic treatment. Advancements in diagnostics for the upper tract Most research on the application of diagnostics on urothelium has been done in the field of bladder cancer. 22-24 However, recent technological improvements have made the optical techniques feasible in the upper urinary tract. We asked the responders if there is an addi- tional benefit in the diagnostic work-up for optical technologies. Many urologists answered that they do not know if the technique is beneficial (12.9-31.43%) or that they are not famil- iar with the technique (8.6-38.7%). Consequently, we conclude that the knowledge on novel techniques is limited, in particular for OCT and CLE. This is possibly due to the fact that only one pilot study has been published, while for CLE just recently a probe became commer- cially available. 25,26_ENREF_26 Therefore the choice for the most promising technique on which we should focus in future studies is difficult. Yet, PDD and urinary biomarkers are likely to be least beneficial in the diagnostic work-up according to the responders. NBI and digital RIRS were best known and scored both high as the most promising tech- nique. PDD was considered not to be beneficial in the diagnosis of UTUC. 27 Surprisingly, SPIES scored well among the responders, while no results have been published to date. The endoscopic imaging modalities (NBI, digital RIRS, SPIES and PDD) allow for integration with OCT and CLE. For this reason, CLE or OCT can be studied in combination with a tech- nique that improves tumour detection in a single study protocol, which can be helpful to assess the summed diagnostic accuracy of several diagnostics in a limited study population. A urinary biomarker, which could reliably diagnose UTUC, would make many of the current and optical diagnostics unnecessary. Although various promising predictive and prognostic biomarkers have been identified, no such validated biomarker is yet available. 28 Therefore, most urologists may not see value of them for the use in UTUC. For this reason we conclude that the existent urinary biomarkers are not likely to be beneficial in the diagnosis of UTUC.