INTRODUCTIONThe diagnosis of UTUC has always presented challenges due to the limitations of available diagnostic tools. Cytology, CTU, and URS with biopsies can all yield inadequate results, leading to false negatives. To minimize the risk of biased diagnosis, a combination of these examinations is essential. The European Association of Urology (EAU) recommends the use of diagnostic ureteroscopy and biopsy when imaging and cytology alone are insufficient for accurate diagnosis and risk stratification of the tumor (1). Similarly, according to the guidelines provided by the American Urological Association (AUA), patients with suspected UTUC should undergo evaluation using diagnostic ureteroscopy. During this procedure, any identified lesion should be biopsied, and cytologic washing from the inspected upper tract system should be performed (2).Regrettably, despite the recommendations and guidelines in place, UTUC is frequently underestimated during pre-operative diagnosis. This underestimation can have serious consequences, leading to delayed or inadequate treatment and contributing to significant mortality rates.