Photodynamic Diagnosis (PDD) in Flexible Cystoscopy
Status:
Completed
Trial end date:
2019-02-01
Target enrollment:
Participant gender:
Summary
Photodynamic diagnostic (PDD) is a technique where a photodynamic drug is installed
preoperatively in the bladder. Mucosa cells with a higher metabolism than normal urothelial
cells, e.g. cancer cells, absorbs this drug which is utilized during cystoscopy where blue
light is absorbed by the drug, making the surgeon able to distinguish tumor cells from normal
cells and thus being able to identify flat lesions and small papillomas missed in white light
cystoscopy.
The use of PDD at this primary transurethral resection of bladder tumour (TURB) has been
shown to be associated with a lower recurrence rate within the first year, probably mostly
owing to a higher detection rate of small papillomas and dysplasia that therefore can be
relevantly treated at an early stage.
Despite the use of PDD at the primary TURB, a high number of patients experience an early
recurrence and patients with carcinoma in situ (CIS) treated with bacillus Calmette-Guerin
(BCG) may have recurrence of their CIS or recurrence of papillomas despite the peroperative
use of PDD.
Whereas the use of PDD is well established in the TURB setting, the use of PDD in the
follow-up setting with flexible cystoscopy in the outpatient clinic is not investigated.
Feasibility studies have been successful but the clinical relevance and benefits have not
been investigated so far.
Thesis The thesis of the study is that the use of PDD in the outpatient clinic in patients
with a high recurrence risk undergoing follow-up flexible cystoscopy will result in diagnosis
of papillomas earlier than by the use of conventional flexible cystoscopy in white light.
Thus, a higher number of tumours can be treated in the outpatient setting without the need
for procedures in general anesthesia. Furthermore, the number of follow-up cystoscopies can
be reduced if PDD is used at the first cystoscopy following TURB.
Aims To investigate whether the use of PDD when performing a flexible cystoscopy in the
outpatient clinic can reduce the number of recurrences of large size papillomas that cannot
be treated by simple fulguration without general anesthesia. Furthermore, to investigate
whether the use of PDD in follow-up cystoscopy in patients with earlier complete response to
BCG on CIS, can increase the detection rate of CIS recurrences.