Posted: Thursday, June 2, 2022
Results of what study authors believe is the first multicenter prospective study, BRIGHT, to investigate the residual tumor rate after initial photodynamic diagnosis–assisted transurethral resection for high-risk non–muscle-invasive bladder cancer have been published in the International Journal of Urology. Hideyasu Matsuyama, MD, PhD, of Yamaguchi University in Ube, Japan, and colleagues found that the use of photodynamic diagnosis assistance (currently available only in Japan) may be an independent preventive factor for residual tumor, compared with the use of white light–assisted transurethral resection of bladder tumor. An ongoing study of 2-year recurrence-free survival will determine the survival advantage of these approaches.
The residual tumor rates at the time of the recommended second planned transurethral resection of bladder tumor were found to be 25.7% and 47.3%, respectively. All else being equal, the odds of residual tumor after an initial photodynamic diagnosis–assisted procedure (which uses oral 5-aminolevulinic acid hydrochloride) were 0.39-fold the odds of residual tumor after initial white-light resection.
Other factors that increased the likelihood of residual tumor in the group that underwent photodynamic diagnosis, however, were smoking history (both current and past), the presence of multiple tumors, and pathologic stage of pT1/pTis. These data were central to the team’s simultaneous goal to create a risk-stratification model to identify cases of high-risk non–muscle-invasive bladder cancer that may not require a second resection. There were two cohorts of patients with this disease: one included 177 prospectively registered patients who had an initial photodynamic diagnosis–assisted resection, and the other had a matched group of 306 similar patients, retrospectively registered, who were treated with initial white light–assisted resection.
When each risk factor—smoking history, more than one tumor, and pT1/pTis stage—was assigned a value of 1, photodynamic diagnosis cases with a total risk score of 1 or less showed a significantly lower residual tumor rate than cases with a total risk score of 2 or more: 8.3% vs. 33.3%, with an odds ratio of 5.46. The authors concluded that their risk stratification model points to the possibility of omitting the second resection in 27% of non–muscle-invasive bladder cancer cases.
Disclosure: The study authors’ disclosure information can be found at onlinelibrary.wiley.com.