Related Experiment Video For aminolevulinic acid
Updated: Feb 1, 2026

Changes in Mammary Gland Morphology and Breast Cancer Risk in Rats
Published on: October 16, 2010
Efficacy of Photodynamic Diagnosis Is Confined to the Low-Risk Subgroup of Intermediate-Risk Non-Muscle-Invasive
Yohei Abe1, Rikiya Taoka1, Asuka Kaji1
1Department of Urology, Faculty of Medicine, Kagawa University, Kagawa, Japan.
Objectives:
Intermediate-risk (IR) non-muscle-invasive bladder cancer (NMIBC) is a heterogeneous disease. In this study, we aimed to evaluate the efficacy of photodynamic diagnosis (PDD)-assisted transurethral resection of the bladder (TURBT) using the recently validated International Bladder Cancer Group (IBCG) risk stratification model for IR-NMIBC.
Methods:
We conducted a single-center retrospective analysis of 193 patients with IR-NMIBC who underwent either PDD-assisted with oral 5-aminolevulinic acid (n = 69) or white-light (WL) TURBT (n = 126) between 2009 and 2023. We performed 1:1 propensity score matching (PSM) to balance baseline characteristics. Recurrence-free survival (RFS) was compared between the groups using the Kaplan-Meier method with subgroup analyses based on IBCG risk strata (IR-low, IR-intermediate/high).
Results:
After PSM, 69 patients with well-balanced characteristics remained in each group. PDD was associated with a significantly improved RFS compared with WL-TURBT in the overall cohort (p = 0.016). Using subgroup analysis, this benefit was most pronounced in the IR-low risk group (p = 0.025), whereas no significant difference was found in the IR-intermediate/high-risk group (p = 0.14). Regarding multivariate analysis, PDD was an independent predictor of improved RFS in both the entire IR cohort (hazard ratio [HR]: 0.421, p = 0.009) and IR-low subgroup (HR: 0.361, p = 0.047).
Conclusions:
PDD-assisted TURBT significantly improved the recurrence outcomes in patients with IR-NMIBC, with the greatest benefit observed in the IR-low risk subgroup. These findings support a stratified approach in which PDD is a cornerstone of management of IR-low patients, while highlighting the need for further research to optimize treatment strategies for IR-intermediate/high patients.
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