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

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.

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.

A Randomized Trial of PHOTOdynamic Surgery in Non-Muscle-Invasive Bladder Cancer.

BACKGROUND: Recurrence of non­muscle-invasive bladder cancer (NMIBC) is common after transurethral resection of bladder tumor (TURBT). Photodynamic diagnosis (PDD) provides better diagnostic accuracy and more complete tumor resection and may reduce recurrence. However, there is limited evidence on the longer-term clinical effectiveness and cost-effectiveness of PDD-guided resection. METHODS: In this pragmatic, open-label, parallel-group randomized trial conducted in 22 U.K. National Health Service hospitals, we recruited participants with a suspected first diagnosis of NMIBC at intermediate or high risk for recurrence on the basis of routine visual assessment before being listed for TURBT. Participants were assigned (1:1) to PDD-guided TURBT or to standard white light (WL)­guided TURBT. The primary clinical outcome was time to recurrence at 3 years of follow-up, analyzed by modified intention to treat. RESULTS: A total of 538 participants were enrolled (269 in each group), and 112 participants without histologic confirmation of NMIBC or who had had cystectomy were excluded. After 44 months' median follow-up, 86 of 209 in the PDD group and 84 of 217 in the WL group had recurrences. The hazard ratio for recurrence was 0.94 (95% confidence interval [CI], 0.69 to 1.28; P=0.70). Three-year recurrence-free rates were 57.8% (95% CI, 50.7 to 64.2) and 61.6% (95% CI, 54.7 to 67.8) in the PDD and WL groups, respectively, with an absolute difference of −3.8 percentage points (95% CI, −13.37 to 5.59) favoring PDD. Adverse events occurred in less than 2% of participants, and rates were similar in both groups, as was health-related quality of life. PDD-guided TURBT was £876 (95% CI, −766 to 2518; P=0.591) more costly than WL-guided TURBT over a 3-year follow-up, with no evidence of a difference in quality-adjusted life years (−0.007; 95% CI, −0.133 to 0.119; P=0.444). CONCLUSIONS: PDD-guided TURBT did not reduce recurrence rates, nor was it cost-effective compared with WL at 3 years. (Funded by the National Institute for Health and Care Research Health Technology Assessment program; ISRCTN number, ISRCTN84013636.)

A novel cell-type deconvolution algorithm reveals substantial contamination by immune cells in saliva, buccal and cervix.

AIM: An outstanding challenge in epigenome studies is the estimation of cell-type proportions in complex epithelial tissues. MATERIALS & METHODS: Here, we construct and validate a DNA methylation reference and algorithm for complex tissues that contain epithelial, immune and nonimmune stromal cells. RESULTS: Using this reference, we show that easily accessible tissues such as saliva, buccal and cervix exhibit substantial variation in immune cell (IC) contamination. We further validate our reference in the context of oral cancer, where it correctly predicts an increased IC infiltration in cancer but suppressed in patients with highest smoking exposure. Finally, our method can improve the specificity of differentially methylated CpG calls in epithelial cancer. CONCLUSION: The degree and variation of IC contamination in complex epithelial tissues is substantial. We provide a valuable resource and tool for assessing the epithelial purity and IC contamination of samples and for identifying differential methylation in such complex tissues.

The multi-omic landscape of transcription factor inactivation in cancer.

BACKGROUND: Hypermethylation of transcription factor promoters bivalently marked in stem cells is a cancer hallmark. However, the biological significance of this observation for carcinogenesis is unclear given that most of these transcription factors are not expressed in any given normal tissue. METHODS: We analysed the dynamics of gene expression between human embryonic stem cells, fetal and adult normal tissue, as well as six different matching cancer types. In addition, we performed an integrative multi-omic analysis of matched DNA methylation, copy number, mutational and transcriptomic data for these six cancer types. RESULTS: We here demonstrate that bivalently and PRC2 marked transcription factors highly expressed in a normal tissue are more likely to be silenced in the corresponding tumour type compared with non-housekeeping genes that are also highly expressed in the same normal tissue. Integrative multi-omic analysis of matched DNA methylation, copy number, mutational and transcriptomic data for six different matching cancer types reveals that in-cis promoter hypermethylation, and not in-cis genomic loss or genetic mutation, emerges as the predominant mechanism associated with silencing of these transcription factors in cancer. However, we also observe that some silenced bivalently/PRC2 marked transcription factors are more prone to copy number loss than promoter hypermethylation, pointing towards distinct, mutually exclusive inactivation patterns. CONCLUSIONS: These data provide statistical evidence that inactivation of cell fate-specifying transcription factors in cancer is an important step in carcinogenesis and that it occurs predominantly through a mechanism associated with promoter hypermethylation.