br The current study reports preliminary
The current study reports preliminary results regarding the role of mUS in the characterization of BC. In patients with TaG3 tumors, the persistence of BC reaches up to 41.4%, and disease persistence in T1 NMIBC ranges between 33% and 55% [21,22]. Therefore, the tumor may be understaged at first instance, and updated guidelines suggest a second resection for restaging. The possibility that MIBC is detected
by a second resection of an initial T1 tumor ranges from 1.3% to 25%, and if the first pathological sample did not contain detrusor muscle, the rate of MIBC may increase up to 45%, making a second-look TUR mandatory. Micro-US accuracy in distinguishing NMIBC from MIBC could help avoid unnecessary re-TUR or guiding TUR when MIBC is suspected. Finally, in patients diagnosed with BC requiring anticoagulant therapy (eg, patients who underwent a recent cardiac surgery under dual antiplatelet therapy), the discrimination between NMIBC and MIBC could be useful to decide the kind and timing of treatment. As an example, the finding of an NMIBC by mUS could eventually promote expectant management of these patients or eventually guide a less invasive TUR.
Several limitations of the current study have to be acknowledged. First, the small sample size limited the statistical significance of our findings. Second, due to the exploratory nature of the current study, we did not perform any comparison between mUS and the available BC staging imaging tools, such as CTU and MRI. As a consequence, future efforts in larger populations comparing the diagnos-tic accuracy of the different imaging techniques are warranted. Third, the mUS probe was not specifically developed for Uridine diphosphate glucose visualization, and this may limit the bladder window in male patients, especially in those with very large prostates. Fourth, the small number of patients included prevented us from determining whether other variables, such as tumor size and location, may act as confounders in discriminating between NMIBC and MIBC. Finally, since mUS provides only longitudinal sections of the bladder, its accuracy to determine the presence/character-istics of a lesion located in the lateral wall may be suboptimal.
High-frequency mUS is feasible and informative, and could be used for discriminating between superficial and invasive BC. Further studies aiming to prove the clinical relevance of this technique in a larger population are mandatory before its introduction in clinical practice.
Author contributions: Nicolò Maria Buffi had full access to all the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.
Study concept and design: Saita, Lughezzani, Buffi, Nava.
Acquisition of data: Hurle, Colombo, Diana, Fasulo, Paciotti, Elefante, Lazzeri.
Analysis and interpretation of data: Saita, Lughezzani, Hurle, Diana.
Drafting of the manuscript: Saita, Lughezzani, Buffi, Diana, Lazzeri.
Critical revision of the manuscript for important intellectual content: Casale, Guazzoni.
Statistical analysis: Lughezzani, Diana, Fasulo, Paciotti.
Obtaining funding: None.
Administrative, technical, or material support: None.
Supervision: Hurle, Lazzeri, Casale, Guazzoni.
Financial disclosures: Nicolò Maria Buffi certifies that all conflicts of interest, including specific financial interests and relationships and
Please cite this article in press as: Saita A, et al. Assessing the Feasibility and Accuracy of High-resolution Microultrasound Imaging for Bladder Cancer Detection and Staging. Eur Urol (2019), https://doi.org/10.1016/j.eururo.2019.03.044
affiliations relevant to the subject matter or materials discussed in the manuscript (eg, employment/affiliation, grants or funding, consultan-cies, honoraria, stock ownership or options, expert testimony, royalties, or patents filed, received, or pending), are the following: None.
Funding/Support and role of the sponsor: None.
Appendix A. Supplementary data
The Surgery in Motion video accompanying this article can be found in the online version at https://doi.org/10. 1016/j.eururo.2019.03.044 and via www.europeanurology. com.
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