Diagnostic performance of photodynamic diagnosis with oral 5-aminolevulinic acid for upper tract- and bladder urothelial carcinoma: a single-centre, retrospective analysis

PurposeTo compare the diagnostic performance of photodynamic diagnosis (PDD) enhanced with oral 5-aminolaevulinic acid between the suspected upper tract urothelial carcinoma (UTUC) and bladder urothelial carcinoma (BUC) cases.MethodsThis retrospective study included 18 patients with suspected UTUC who underwent ureteroscopy (URS) with oral 5-ALA in the PDD-URS cohort between June 2018 and January 2019; and 110 patients with suspected BUC who underwent transurethral resection of bladder tumour (TURBT) in the PDD-TURBT cohort between January 2019 and March 2023. Sixty-three and 708 biopsy samples were collected during diagnostic URS and TURBT, respectively. The diagnostic accuracy of white light (WL) and PDD in the two cohorts was evaluated, and false PDD-positive samples were pathologically re-evaluated.ResultsThe area under the receiver operating characteristic curve (AUC) of PDD was significantly superior to that of WL in both cohorts. The per biopsy sensitivity, specificity, and positive and negative predictive values of PDD in patients in the PDD-URS and PDD-TURBT cohorts were 91.2 vs. 71.4, 75.9 vs. 75.3, 81.6 vs. 66.3, and 88.0 vs. 79.4%, respectively. The PDD-URS cohort exhibited a higher AUC than did the PDD-TURBT cohort (0.84 vs. 0.73). Seven of four false PDD-positive samples (57.1%) in the PDD-URS cohort showed potential precancerous findings compared with eight of 101 (7.9%) in the PDD-TURBT cohort.ConclusionThe diagnostic performance of PDD in the PDD-URS cohort was at least equivalent to that in the PDD-TURBT cohort.