Identification of risk factors associated with oral 5-aminolevulinic acid induced adverse events in photodynamic diagnosis−transurethral resection of bladder tumor

Background: Oral 5-aminolevulinic acid for transurethral resection of bladder tumor reduces bladder cancer recurrence compared with standard white-light transurethral resection of bladder tumor. However, data regarding risks of adverse events with this drug are unclear. The aim of the present study was to identify risk factors associated with oral 5-aminolevulinic acid induced adverse events in photodynamic diagnosis-transurethral resection of bladder tumor. Methods: We studied 104 cases of 5-aminolevulinic acid-photodynamic diagnosis-transurethral resection of bladder tumor from October 2021 to April 2023, administering 20 mg/kg 5-aminolevulinic acid orally at least 2 h pre-surgery. Four major adverse events associated with 5-aminolevulinic acid were selected to identify risk factors for their occurrence, including perioperative hypotension, nausea and/or vomiting, photosensitivity, and liver dysfunction. Univariate and multivariate analyses were conducted to identify the risk factors of those adverse events. Results: Perioperative hypotension (11.5 %), nausea and/or vomiting (37.5 %) photosensitivity (31.7 %), and liver dysfunction (51.9 %) were observed. Multivariate analyses revealed that spinal anesthesia was associated with hypotension (p = 0.02), whereas advanced age (p < 0.01) and higher body mass index (p < 0.01) were associated with nausea and/or vomiting. Also, male sex (p < 0.01) and longer operative time (p = 0.01) were associated with photosensitivity, and renin-angiotensin system inhibitors use was associated with postoperative liver dysfunction (p < 0.01). Conclusions: For elderly male obese patients taking renin-angiotensin system inhibitors, particular attention is needed during the perioperative period of photodynamic diagnosis-transurethral resection of bladder tumor under spinal anesthesia due to the higher risk of onset of the adverse events involved in oral administration of 5-aminolevulinic acid.