Near Infrared Fluorescence Imaging for Bladder Cancer Detection: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Near Infrared Fluorescence Imaging for Bladder Cancer Detection (NCT03058705), a na na study. The primary outcome is Minimal Dwell Time.

2. Clinical Question

As general background, dwell time is the interval between administration of an agent and the assessment for the intended signal. In this study, the signal of interest was protoporphyrin IX near infrared fluorescence associated with hexaminolevulinate-avid tumors. The study aim was therefore about whether an observable signal could be obtained at a usable time point, rather than a comparison of clinical outcomes between treatment groups.

The record identifies the study as a pilot and lists an enrollment of 10. It does not report a numerical estimate of detection performance, a minimum dwell time, or a between-group effect. With no collected primary endpoint and no control arm, the central question remains unanswered by the posted outcome data.

3. Trial Design

The registry describes a completed, single-group pilot study of near infrared fluorescence imaging for bladder cancer detection. Enrollment is listed as 10. The intervention group is described as receiving hexaminolevulinate HCL with near infrared fluorescence imaging; the registry separately lists the drug and device as interventions. The study is not described as randomized, and masking is listed as none. Phase and allocation are listed as not applicable.

The procedural description says that during transurethral resection, the bladder would initially be examined systematically. Suspicious tumors identified by white light only, near infrared fluorescence only, or both were to be identified. The description ends before giving the complete procedural account, so details beyond that point are not reported in the registry record. In particular, the full schedule for assessing dwell time and the criteria for adequate detection are not available in the record.

The study began on 2017-11-28, and primary completion is listed as 2018-07-25. Its status is completed. These administrative details indicate that the registry marks the study as finished; they do not establish that its intended endpoint was successfully measured. The posted primary outcome explicitly states that dwell time was not collected on any participant because visual fluorescence was not observed in the subjects.

A single-group design can describe what was observed under the study procedure, but it does not by itself estimate a contrast against a concurrent control group. The registry does not report an assigned comparison between imaging methods or dwell-time regimens. Although the procedural description refers to white light and fluorescence findings, those observations do not create randomized comparison groups. The record also does not report a statistical analysis plan or any posted analyses.

4. Participant Flow and Accounting

The registry reports how participants moved through each stage of the study. All counts below are exactly as posted; missing counts are not inferred from other stages.

Overall Study

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: Dwell time was not collected on any participant due to failure to visual fluorescence in the subjects.

5. Baseline Characteristics

The table reproduces the baseline characteristics posted in the registry, which describe the participants analysed at baseline and help show whether the randomized groups were comparable.

6. Primary Endpoint

The registry lists the primary outcome as Minimal Dwell Time, measured over Day 1.

The primary endpoint is titled “Minimal Dwell Time.” It is defined as the minimum time needed to observe tumors during transurethral resection of bladder tumor, with a timeframe of Day 1. The study summary frames the objective as determining the minimum dwell time needed for adequate detection of hexaminolevulinate HCL-avid tumors using protoporphyrin IX near infrared fluorescence.

As general background, a dwell-time endpoint can help characterize the timing needed before an imaging signal is assessed. It is useful only if the signal can be observed and the timing can be recorded according to a defined procedure. A clearly specified endpoint can also support comparison across participants or imaging conditions, if the design and data permit such comparisons.

In this record, the endpoint was not collected on any participant because visual fluorescence was not observed in the subjects. Thus, the registry supplies neither a minimum dwell-time value nor participant-level timing observations. The objective and endpoint definition are available, but the endpoint result is not. The record also does not report a threshold defining “adequate” detection or a numerical tumor-detection result that could substitute for the missing timing measure.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry identifies a single-group pilot design and reports no analyses. This means there is no posted statistical comparison or inferential result to interpret. The methods discussion below gives general context for the kinds of statistical questions that would arise in a study of this type; it does not describe analyses documented as having been performed in this trial.

What would the endpoint estimate represent?

As general background, a minimum dwell-time endpoint could be treated as a timing measure: the time associated with first observing a defined fluorescence signal under a specified procedure. To interpret such a measure, the endpoint definition would need to clarify how observation is judged, when timing begins, how assessments are scheduled, and what counts as adequate detection. The registry states the endpoint purpose and timeframe, but these operational details and a numerical adequacy threshold are not reported in the registry record.

If measurements existed, a descriptive summary could convey the observed timing and its variability. A confidence interval, in general, describes uncertainty around an estimated quantity under the assumptions of the analysis. It does not correct for an outcome that was never measured, and it cannot be calculated from a missing endpoint without additional data. No dwell-time estimate or confidence interval is posted for this study.

Why is a single-group design important?

As general background, a single-group study can describe observations made among participants receiving the study procedure. Without a separate comparison group, it cannot directly estimate how outcomes would differ under another intervention or procedure. Randomization, when used, helps make comparison groups more alike on average; this record does not describe random allocation. The registry lists allocation as not applicable and identifies the model as single group.

The procedural description includes white-light and fluorescence observations, but no results by observation category are reported. The description therefore does not support a calculated contrast between the methods. A comparison would require defined outcomes for each method and a suitable analysis of those outcomes. Neither a comparative dataset nor a comparative analysis is posted.

What does the missing endpoint imply for analysis?

The registry says dwell time was not collected on any participant because visual fluorescence was not observed. This is more than an ordinary incomplete timing record: the stated reason is that the signal required for the endpoint was not seen. A statistical analysis cannot estimate the minimum time to observe a signal when the record contains no observations of that signal. Treating the missing values as a particular time, or as a quantitative detection failure rate, would require assumptions and data not reported in the registry record.

In general, missing-data methods depend on why data are missing, what other measurements are available, and the target question. Such methods can address some incomplete datasets under explicit assumptions, but they cannot create direct evidence about an unobserved endpoint. Here, the record does not describe participant-level measurements, auxiliary data for modeling the missing endpoint, or a missing-data analysis.

How should planning calculations be read?

The registry’s planning assumptions describe an illustration based on an observed effect, with a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. The assumptions also distinguish planning for a stated fraction of an observed effect and describe whether an illustration is expressed as participants per arm or total events. These are planning conventions, not a description of the registered single-group design.

Sample-size illustrations answer a hypothetical design question: under specified assumptions, what scale of study might be needed to detect an assumed effect? They do not report a trial outcome, establish that an effect was observed, or show the probability that this completed study detected an effect. Such planning figures are not observed power. In this case, the two-arm, equal-allocation assumptions do not match the registry’s single-group design. The primary endpoint was also not collected, so the record provides no endpoint estimate to interpret as an observed effect.

What can be concluded from the statistical record?

The registry reports one outcome measure and zero analyses. It supplies the endpoint definition and the reason the endpoint was not collected, but it does not provide an estimate, distribution, treatment contrast, p-value, or confidence interval for the primary question. Without those results, statistical significance and precision cannot be assessed. The appropriate reading is that the primary statistical question was not answered by the posted endpoint data, not that a statistical test found no effect.

10. Multiplicity, Missing Data and Analysis Populations

The registry lists one outcome measure and zero analyses. It does not report a prespecified statistical analysis plan, a hierarchy of endpoints, or a procedure for controlling multiplicity. Multiplicity refers, in general, to the increased chance of misleading findings when several hypotheses or outcomes are tested. No multiplicity adjustment or testing strategy is reported in the registry record, and the absence of posted analyses means there are no multiple test results to evaluate.

The primary outcome, minimal dwell time, was not collected on any participant because visual fluorescence was not observed in the subjects. The record does not explain whether any other data were collected to characterize this outcome, nor does it describe imputation or another missing-data method. It would not be appropriate to substitute a value for the uncollected endpoint or to infer a numerical detection rate from the statement that fluorescence was not observed.

The registry does not report analysis populations, such as a defined intention-to-treat or per-protocol population, nor does it describe exclusions or participant-level data availability beyond the primary endpoint statement. Enrollment is listed as 10, but the record does not give a flow of participants through the procedures or explain whether any participants were excluded from safety summaries. The analysis population and handling of missing endpoint information are therefore not reported in the registry record.

These omissions limit reproducibility and interpretation. Without an analysis plan, it is not possible to assess whether endpoint definitions or analyses changed over time. Without participant-level outcome data or an analysis population definition, it is not possible to independently evaluate the endpoint or determine how missing observations were handled beyond the stated lack of collection.

11. Safety Results

The registry reports serious adverse events as affected participants divided by participants at risk.

Deaths

Other (non-serious) adverse events

Participants with at least one non-serious event at or above the registry's 0% reporting threshold.

The registry’s adverse-event figures list 10 participants at risk for serious adverse events and 0 affected. For other adverse events, it lists 10 at risk and 0 affected. Deaths are listed as 0. These are the posted safety counts for the group titled Hexaminolevinulate HCL With Near Infrared Fluorescence (NIRF).

As general background, “at risk” is the denominator recorded for a safety outcome, while “affected” is the count recorded with that outcome. A count of zero means no events in that category were recorded in the posted results; it does not establish that an intervention has no risk. Interpretation depends on the collection and reporting procedures, observation period, and completeness of follow-up, details that are not reported in the registry record.

The safety figures are separate from the primary endpoint. They do not show whether fluorescence was visualized or establish a minimum dwell time. The record does not list serious adverse-event terms, and it does not provide detail about event definitions or the timing of safety surveillance. Accordingly, the counts should be understood narrowly as the registry’s reported figures, not as a comprehensive assessment of safety beyond this study.

12. What the Result Does, and Does Not, Mean

The record establishes that the study was designed to explore near infrared fluorescence imaging for bladder cancer detection and to determine the minimum dwell time needed to observe tumors. It also establishes that the primary endpoint was not collected because visual fluorescence was not observed in the subjects. Thus, the posted results do not identify a dwell time or quantify the detection outcome.

This is not the same as a statistical finding that the imaging approach had no effect. A null statistical result would ordinarily require a defined analysis and an estimate with uncertainty, or a test result. The registry reports no analyses and provides no endpoint estimate. There is therefore no inferential result that supports either a positive or a negative comparative conclusion.

The record also does not support a comparison with white-light examination. Although the procedural description refers to identifying suspicious tumors seen by white light only, near infrared fluorescence only, or both, it does not report counts or comparative analyses for those categories. A comparison cannot be reconstructed from the descriptions alone.

The study’s completed status and enrollment listing of 10 provide context about the registry record, but they do not change the absence of primary endpoint data. Nor do the posted safety counts resolve the detection question. The report lists 0 serious adverse events, 0 other adverse events, and 0 deaths, but these counts address different outcomes.

In practical statistical terms, the central result is an inability to estimate the intended timing endpoint from the posted data. Any claim about the minimum time needed, the proportion of tumors visualized, or differences between imaging strategies would go beyond what the registry reports. The findings therefore describe an endpoint measurement failure, rather than a quantified estimate of detection performance.

13. Why This Trial Matters Statistically

This trial is statistically instructive because it separates a study objective from an analyzable result. The registry gives a clear question—what minimum dwell time is needed to observe tumors—but then reports that the endpoint was not collected because fluorescence was not visualized. Stating the reason for missing outcome data is important: it prevents readers from mistaking a missing measurement for a measured time or a conventional null result.

The record also illustrates the importance of matching a planning calculation to the actual design. The described sample-size assumptions use equal allocation between two arms, while the registered study is single-group. As general statistical practice, a planning illustration is meaningful only in relation to its assumptions; it is not evidence that those assumptions match the conducted study. It is also not observed power or a substitute for endpoint results.

Another statistical lesson is that a procedural description is not a comparative analysis. Mentioning findings under white light and fluorescence does not establish that counts, estimates, or contrasts were reported. Clear distinction between intended observations and posted outcome data helps prevent overinterpretation.

Finally, the record shows why endpoint feasibility is itself informative for interpreting a pilot. If the signal needed to define an endpoint is not observed, the planned timing question cannot be estimated from those data. The record documents that limitation but does not explain its cause beyond failure to visualize fluorescence. It can therefore inform readers about what the registry reports while leaving the mechanism and broader implications unresolved.

14. Limitations

• The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
• Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.

The most consequential limitation is that the primary endpoint was not collected on any participant. The registry attributes this to failure to visualize fluorescence in the subjects. As a result, there is no posted estimate of minimal dwell time, no description of its variability, and no measure of uncertainty for the primary question.

The registry does not provide participant characteristics, detailed eligibility criteria, or a complete account of the procedure. The intervention arm description is incomplete in the record, ending mid-sentence. Further procedural details, including the complete timing schedule and criteria for adequate fluorescence detection, are not reported in the registry record. These gaps make it difficult to assess how the intended endpoint was operationalized.

The single-group design does not provide a randomized control comparison. Although the procedural description references white-light and fluorescence observations, outcome counts for these categories and comparative analyses are not reported. Generalizability is also difficult to assess because participant characteristics and setting details are not available in the record.

The registry lists no analyses and does not report a statistical analysis plan, analysis populations, handling of missing endpoint data, or multiplicity procedures. The safety counts are available, but event definitions and the surveillance period are not reported. Finally, the planning assumptions describe a two-arm illustration that does not match the registered single-group design. These limitations constrain interpretation of both the endpoint and any planning calculations associated with the record.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Near Infrared Fluorescence Imaging for Bladder Cancer Detection — NCT03058705.
• Registry record last updated 2019-08-19; status last verified 2019-08.
• Results first posted 2019-08-19.
• Data retrieved from ClinicalTrials.gov on 2026-11-09.
• Group sizes, means, event counts and sponsor-reported p-values are reproduced as posted. Effect estimates, confidence intervals and p-values not attributed to the sponsor are independently calculated from the posted summary statistics.

18. Record Summary

The registry record describes NCT03058705, a completed single-group pilot study titled “Near Infrared Fluorescence Imaging for Bladder Cancer Detection.” It lists an enrollment of 10, a start date of 2017-11-28, and primary completion on 2018-07-25. The intervention combines hexaminolevulinate HCL and near infrared fluorescence imaging.

The primary outcome is minimal dwell time, defined as the minimum time needed to observe tumors during transurethral resection of bladder tumor, with a timeframe of Day 1. The registry states that dwell time was not collected on any participant because visual fluorescence was not observed in the subjects. It lists one outcome measure and zero analyses.

The record lists 0 serious adverse events among 10 at risk, 0 other adverse events among 10 at risk, and 0 deaths. These safety counts do not resolve the uncollected imaging endpoint. The registry does not provide a minimum dwell-time estimate or a comparative analysis.