(UroToday.com) The 2025 European Association of Urology (EAU) Annual Congress held in Madrid, Spain between March 21st and 24th 2025, was host to an abstract session on the latest advances in the diagnosis and follow-up of non-muscle invasive bladder cancer (NMIBC). Dr. Peter Blak Hjort presented a nationwide follow-up study on the impact of photodynamic diagnosis (PDD) on recurrence and progression rates in BCG-treated NMIBC patients.
Owing to its improved sensitivity compared to white light cystoscopy, PDD has emerged as a popular modality for the surveillance of NMIBC patients. Interestingly, evidence from animal studies suggests that PDD may influence the response to Bacillus Calmette-Guérin (BCG) therapy. However, clinical studies confirming the association between PDD and BCG treatment outcomes remains limited. This study aimed to investigate the potential impact of PDD on recurrence and progression rates in NMIBC patients treated with BCG therapy using a nationwide cohort of Danish patients.
Dr. Hjort and colleagues conducted a nationwide cohort study using Danish registry data, including patients diagnosed with a primary NMIBC between 2009 and 2022 and who subsequently received intravesical BCG therapy. Patients were followed until death, cystectomy, or December 31, 2023, whichever occurred first. BCG response was assessed according to PDD-status at the time of the 1st TURBT. Cumulative incidences and relative rates for recurrence and progression were compared between the PDD and non-PDD groups. Additionally, crude and adjusted odds ratios for BCG-response were estimated based on PDD status.
The study cohort included a total of 4,318 patients with a first-time NMIBC diagnosis and who subsequently received BCG. Of these, 2,388 (55%) patients were diagnosed using PDD. Baseline characteristics, including demographics, tumor stage, and grade were comparable between the two groups.
No significant differences in BCG response rates were observed between the two groups. The age-adjusted relative risk for recurrence was 0.88 (95% CI: 0.79–0.97) at 1 year and 0.97 (95% CI: 0.89–1.05) at 5 years for the PDD group, compared to the non-PDD group. For progression, the age-adjusted relative risk was 0.93 (95% CI: 0.73–1.19) at 1 year and 1.01 (95% CI: 0.84–1.21) at 5 years for the PDD group.
Dr. Hjort noted that given that the BCG response was comparable across groups, the reduced risk of recurrence at 1 year was likely secondary to PDD’s improved detection ability, rather than representing a treatment interaction effect with BCG therapy. Notable limitations of the study include the lack of data on tumor size and number from the tumor registry, as well as a potential detection bias, with more tumors diagnosed in the PDD group at the time of diagnosis.
Dr. Hjort noted that the findings of this study did not support the hypothesis that PDD modulates responses to BCG therapy in NMIBC patients. Instead, the data suggests that PDD’s impact on recurrence and progression rates is more likely related to improved tumor detection with PDD. Further research is needed to explore the role of PDD in different risk groups of NMIBC patients and to investigate the underlying mechanisms of its potential impact on disease recurrence and progression.
Presented by: Peter Blak Hjort, MD, Department of Urology, Aarhus University Hospital, Aarhus, Denmark
Written by: Rashid K. Sayyid, MD, MSc – Robotic Urologic Oncology Fellow at The University of Southern California, @rksayyid on Twitter during the 2025 European Association of Urology (EAU) Annual Congress held in Madrid, Spain between March 21st and 24th, 2025