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Published on: April 16, 2018
Skin Phototoxicity With Aminolevulinic Acid Hydrochloride in Patients With Non-Muscle Invasive Bladder Cancer:
Asami Usui1, Tomohiko Hara1, Suguru Oka1
1Department of Urology, Toranomon Hospital, Tokyo, Japan.
Objectives:
The study quantifies the real-world incidence of skin phototoxicity associated with oral 5-aminolevulinic acid hydrochloride during photodynamic diagnosis-assisted transurethral resection of bladder tumor. Furthermore, we assessed whether the Japanese regulatory revision in 2022 on the concomitant use with photosensitizing medications modified the risk.
Methods:
We retrospectively analyzed 462 procedures performed at Toranomon Hospital between 2020 and 2024. The clinical data included demographics, laboratory results, medication history, and adverse reactions. Skin reactions were graded using the Common Terminology Criteria for Adverse Events, version 5.0. Logistic regression, including Firth's penalized likelihood, was used to identify independent predictors.
Results:
Phototoxicity occurred in eleven procedures (all grade 1), and all patients recovered without complications. Skin phototoxicity occurred in one of 190 patients (0.5%) without photosensitizing agents and in 10 of 272 patients (3.7%) with the concomitant use of photosensitizing agents. The unadjusted relative risk was 7.0, and the absolute risk increase with photosensitizing drugs was 3.2% (number needed to harm, 32). Concomitant photosensitizing drugs and elevated preoperative alanine aminotransferase grade were independently associated with phototoxicity in univariate and multivariate analyses (p < 0.05). The most frequently used concomitant medications included calcium-channel blockers, angiotensin receptor blockers, statins, and thiazide diuretics.
Conclusions:
Skin phototoxicity related to oral 5-aminolevulinic acid hydrochloride during photodynamic diagnosis-assisted transurethral resection of bladder tumor is uncommon and mild. Although the continued use of photosensitizing medications and elevated alanine aminotransferase levels increased the risk of phototoxicity, careful medication review and standard light-avoidance measures can support the safe use of 5-aminolevulinic acid hydrochloride.
