Photodynamic diagnostic ureterorenoscopy: A valuable tool in the detection of upper urinary tract tumour

Abstract

Background: Photodynamic diagnosis increases the detection rate and hence decreases recurrence rates of urothelial cancer (UC) of the bladder. This technique has been implemented in the upper urinary tract and like in the bladder, has shown to increase the detection rate of urothelial lesions.

Objectives: To determine the sensitivity, specificity, and detection rates for photodynamic diagnostic flexible ureterorenoscopy (PDD-FURS) and white light ureterorenoscopy (WL-FURS). Design between 2009 and 2013, PDD-FURS was performed within 106 Upper urinary tract (UUT) Units (Mean age-72.6±9.5). Indications for the procedure included abnormal upper urinary tract on imaging, normal flexible cystoscopy with abnormal urine cytology, endoscopic treatment and follow-up of UUT UC. Oral 5-aminolevulinic acid was used as the photosensitizer administered 3-4 h pre-operatively.

Results: 48 lesions were detected, of which 95.8% (46/48) where visualised by PDD-FURS compared to 47.9% (23/48) shown by WL-FURS (P<0.0001). PDD-FURS detected significantly more carcinoma in situ (CIS) or dysplasia lesions than WL-FURS (93.75% (15/16) vs. 18.75% (3/16), respectively, (P=0.0006)). Furthermore, PDD-FURS detected significantly more UC lesions than WL-FURS (96.9% (31/32) vs. 62.5% (20/32) (P=0.007)). PDD-FURS was more sensitive (95.8; range: 85.7-99.5) than WL-FURS (53.5; range: 37.7-68.8) in detecting UUT-UC (P<0.0001). There was no difference (P=0.716) in the specificity between PDD-FURS (96.6; range: 88.1-99.6) and WL-FURS (95.2; range: 86.7-99).

Conclusions: Our results PDD-FURS with oral 5-ALA as photosensitizer suggest higher sensitivity and detection rate of urothelial tumours than WL-FURS, with a good safety profile. In our series, PDD-FURS enhanced the visualisation of flat lesions, such as CIS and dysplasia that otherwise would have been missed.

Keywords: 5-Aminolevulinic acid; Cystoscopy; Haematuria; Photodynamic diagnosis; Upper urinary tract tumour; Ureterorenoscopy.