Background: Despite widely adopted standard methods for follow-up including cystoscopy plus cytology, recurrence rates of non muscle-invasive bladder cancer (NMIBC) have not improved over the past decades, still ranging from 60% through 70%. Hence, widely acceptable surveillance strategies with excellent sensitivity are needed. Early recurrence has led to the development of a novel cystoscopy technique utilizing photodynamic diagnosis (PDD). Although, no studies have evaluated the efficacy of PDD for patients of MIBC, BCG failure or 2nd-transurethelial resection (TUR).
Materials and methods: The present study was performed from October 2012 through May 2013. IRB approved 25 patients initially underwent a cystoscopy examination of white light and blue light followed by the resection of tumors identified. Resections were performed from bladder mucosa areas considered suspicious at PDD, along with PDD negative normal bladder mucosa area resected by random biopsy. Specimens were divided into two groups, PDD positive and negative. Primary endpoints were sensitivity and specificity.
Results: A total of 147 specimens extracted from 25 patients were included in the analysis. Some 45 out of 92 PDD-positive specimens were confirmed to have bladder cancer, and 51 out of PDD-negative 55 specimens were confirmed to be cancer negative. The sensitivity of PDD was 91.8% (45/49) and specificity was 52.0% (51/98). The sensitivity:specificity was 89.5% (17/19) : 47.6% (30/63) in 12 2nd-TUR patients, 90.5% (19/21) : 61.1% (11/18) in seven MIBC patients, and 95.0% (19/20) : 48.5% (16/33) in eight failed BCG cases.
Conclusions: PDD-TURBT has high sensitivity to diagnose BC even for 2nd-TUR, MIBC or BCG failure cases.