Photodynamic versus white-light-guided resection of first-diagnosis non-muscle-invasive bladder cancer: PHOTO RCT

Health Technol Assess. 2022 Oct;26(40):1-144. doi: 10.3310/PLPU1526.

Abstract

Background: Around 7500 people are diagnosed with non-muscle-invasive bladder cancer in the UK annually. Recurrence following transurethral resection of bladder tumour is common, and the intensive monitoring schedule required after initial treatment has associated costs for patients and the NHS. In photodynamic diagnosis, before transurethral resection of bladder tumour, a photosensitiser that is preferentially absorbed by tumour cells is instilled intravesically. Transurethral resection of bladder tumour is then conducted under blue light, causing the photosensitiser to fluoresce. Photodynamic diagnosis-guided transurethral resection of bladder tumour offers better diagnostic accuracy than standard white-light-guided transurethral resection of bladder tumour, potentially reducing the chance of subsequent recurrence.

Objective: The objective was to assess the clinical effectiveness and cost-effectiveness of photodynamic diagnosis-guided transurethral resection of bladder tumour.

Design: This was a multicentre, pragmatic, open-label, parallel-group, non-masked, superiority randomised controlled trial. Allocation was by remote web-based service, using a 1 : 1 ratio and a minimisation algorithm balanced by centre and sex.

Setting: The setting was 22 NHS hospitals.

Participants: Patients aged ≥ 16 years with a suspected first diagnosis of high-risk non-muscle-invasive bladder cancer, no contraindications to photodynamic diagnosis and written informed consent were eligible.

Interventions: Photodynamic diagnosis-guided transurethral resection of bladder tumour and standard white-light cystoscopy transurethral resection of bladder tumour.

Main outcome measures: The primary clinical outcome measure was the time to recurrence from the date of randomisation to the date of pathologically proven first recurrence (or intercurrent bladder cancer death). The primary health economic outcome was the incremental cost per quality-adjusted life-year gained at 3 years.

Results: We enrolled 538 participants from 22 UK hospitals between 11 November 2014 and 6 February 2018. Of these, 269 were allocated to photodynamic diagnosis and 269 were allocated to white light. A total of 112 participants were excluded from the analysis because of ineligibility (n = 5), lack of non-muscle-invasive bladder cancer diagnosis following transurethral resection of bladder tumour (n = 89) or early cystectomy (n = 18). In total, 209 photodynamic diagnosis and 217 white-light participants were included in the clinical end-point analysis population. All randomised participants were included in the cost-effectiveness analysis. Over a median follow-up period of 21 months for the photodynamic diagnosis group and 22 months for the white-light group, there were 86 recurrences (3-year recurrence-free survival rate 57.8%, 95% confidence interval 50.7% to 64.2%) in the photodynamic diagnosis group and 84 recurrences (3-year recurrence-free survival rate 61.6%, 95% confidence interval 54.7% to 67.8%) in the white-light group (hazard ratio 0.94, 95% confidence interval 0.69 to 1.28; p = 0.70). Adverse event frequency was low and similar in both groups [12 (5.7%) in the photodynamic diagnosis group vs. 12 (5.5%) in the white-light group]. At 3 years, the total cost was £12,881 for photodynamic diagnosis-guided transurethral resection of bladder tumour and £12,005 for white light. There was no evidence of differences in the use of health services or total cost at 3 years. At 3 years, the quality-adjusted life-years gain was 2.094 in the photodynamic diagnosis transurethral resection of bladder tumour group and 2.087 in the white light group. The probability that photodynamic diagnosis-guided transurethral resection of bladder tumour was cost-effective was never > 30% over the range of society's cost-effectiveness thresholds.

Limitations: Fewer patients than anticipated were correctly diagnosed with intermediate- to high-risk non-muscle-invasive bladder cancer before transurethral resection of bladder tumour and the ratio of intermediate- to high-risk non-muscle-invasive bladder cancer was higher than expected, reducing the number of observed recurrences and the statistical power.

Conclusions: Photodynamic diagnosis-guided transurethral resection of bladder tumour did not reduce recurrences, nor was it likely to be cost-effective compared with white light at 3 years. Photodynamic diagnosis-guided transurethral resection of bladder tumour is not supported in the management of primary intermediate- to high-risk non-muscle-invasive bladder cancer.

Future work: Further work should include the modelling of appropriate surveillance schedules and exploring predictive and prognostic biomarkers.

Trial registration: This trial is registered as ISRCTN84013636.

Funding: This project was funded by the National Institute for Health and Care Research ( NIHR ) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 26, No. 40. See the NIHR Journals Library website for further project information.

Keywords: BLADDER CANCER; NON-MUSCLE-INVASIVE BLADDER CANCER; PHASE III: TRANSURETHRAL RESECTION; PHOTODYNAMIC DETECTION; RANDOMISED TRIAL; SURGERY; TRANSURETHRAL RESECTION OF BLADDER TUMOUR; URINARY BLADDER NEOPLASMS.

Plain language summary

Around 7500 people are diagnosed with early-stage bladder cancer in the UK each year. Early bladder cancer is contained within the bladder and has not yet invaded the bladder’s muscle wall or spread elsewhere in the body. The cancer will return (recur) in around half of people after initial treatment and they have to attend hospital for regular check-ups, with costs to both them and the NHS. The first step in treating early bladder cancer is surgery to remove the tumour. This surgery is normally performed under white light. Photodynamic diagnosis is a new technique in which a liquid is put into the patient’s bladder before surgery and a blue light is used during the operation. This causes the bladder cancer to fluoresce so that it can be seen more easily by the surgeon. The Photodynamic versus white-light-guided resection of first diagnosis non-muscle-invasive bladder cancer ( PHOTO ) trial aimed to find out whether or not using photodynamic diagnosis at initial surgery would reduce how often the cancer recurred and whether or not this could reduce the cost of treating early bladder cancer. A total of 538 people with early bladder cancer who had a medium to high chance of their cancer returning after treatment were enrolled in the PHOTO trial. They were included in one of two treatment groups, at random: 269 had photodynamic surgery and 269 had standard white-light surgery. People in both groups were monitored regularly for any recurrences, with further treatment as appropriate. After 3 years, 4 out of 10 people in each group had a recurrence of their bladder cancer. We found no difference between the treatment groups in the number of people with recurrences. We found no evidence of a benefit to patients, and the total costs of photodynamic surgery were higher than those of standard white light. We therefore recommend that it is no longer used in the treatment of this group of patients.

Publication types

  • Randomized Controlled Trial
  • Multicenter Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biomarkers
  • Cost-Benefit Analysis
  • Humans
  • Light
  • Photochemotherapy
  • Quality of Life
  • Quality-Adjusted Life Years
  • Technology Assessment, Biomedical
  • Urinary Bladder Neoplasms* / diagnosis
  • Urinary Bladder Neoplasms* / surgery

Substances

  • Biomarkers

Associated data

  • ISRCTN/ISRCTN84013636