The current role of photodynamic diagnosis (PDD) in the management of non-muscle invasive bladder cancer: the Italian Society of Urology (SIU) Position Paper.

Photodynamic diagnosis (PDD) significantly enhances the detection of bladder cancer (BCa) and is able to reduce the risk of disease recurrence, although it may not affect disease progression and mortality rates. Despite its advantages, widespread adoption of PDD is limited by cost considerations and the absence of unified guidelines on its application, highlighting the need for continued evaluation of its cost-effectiveness across different healthcare settings. To date, no specific recommendations for PDD in non-muscle invasive bladder cancer (NMIBC) management have been provided by the Italian Society of Urology (Società Italiana di Urologia, SIU). Therefore, the aim of this paper is to report on the position of SIU on the role of PDD in NMIBC. According to available evidence and international guidelines (i.e., European Association of Urology, American Association of Urology, National Comprehensive Cancer Network and other national guidelines) on BCa, a Panel of twelve Italian urologists with long and renowned experience in treating BCa defined current indications for PDD in the management of NMIBC. The final document was ultimately reviewed and approved by the expert Panel prior to publication. The consensus highlighted the role of PDD during the initial transurethral resection of the bladder (TURB) to detect carcinoma in situ (CIS) and small papillary lesions that might otherwise be missed, leading to disease persistence. Additionally, in clinical scenarios such as positive urine cytology with negative cystoscopy, PDD-guided biopsies can significantly increase the detection of CIS. For cases involving larger or multifocal tumors, or atypical macroscopic features during cystoscopy, PDD is valuable for identifying subtle high-grade disease elements, thereby facilitating more precise risk stratification and targeted treatment planning. In the setting of re-TURB, aiming to detect the presence and extent of concomitant CIS and to gain all possible additional information, PDD may be used in all procedures if not already performed during initial resection. Finally, PDD may be used for disease recurrence in patients with a history of HG NMIBC and to evaluate the response of CIS to Bacillus Calmette-Guérin (BCG). This position paper of the SIU highlights the current recommendation for the use of PDD in the management of NMIBC, from initial TURB, to re-TURB and follow-up.