This page provides an independent statistical analysis and educational interpretation of publicly reported results. ClinicalTrials.gov provides the official trial registry record. Numerical trial results on this page are restricted to the results posted in the ClinicalTrials.gov record; calculations added by Clinical Biostats are labelled as such.
1. Trial at a Glance
This page covers the registry results for Radiation Therapy in Preventing Liver Metastases in Patients With Uveal Melanoma Who HaveMonosomy 3 or DecisionDx Class 2 Disease and Are More Likely to Develop Liver Metastases (NCT02336763), a na na study. The primary outcome is Progression-free Survival.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT02336763 |
| Phase | NA |
| Condition | Iris Melanoma, Medium/Large Size Posterior Uveal Melanoma, Stage IIA Uveal Melanoma |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 2 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Jonsson Comprehensive Cancer Center |
| Results posted | Yes |
2. Clinical Question
Population
People with uveal melanoma and either monosomy 3 or DecisionDx Class 2 disease were the intended population. The registry lists iris melanoma and medium/large size posterior uveal melanoma, as well as Stage IIA, IIB, IIIA, IIIB, and IIIC uveal melanoma among the conditions. These descriptions identify the clinical setting, but the registry does not report a detailed eligibility rule explaining how the condition and risk-marker descriptions were applied together.
Intervention
The intervention was external beam radiation therapy directed to the liver, described as prophylactic hepatic irradiation. The treatment description says radiation was given daily over 20 minutes on Monday-Friday for up to 10 fractions over approximately 2 weeks. Laboratory biomarker analysis was also listed as an intervention.
Comparator
There was no comparator arm in the registry design. Allocation is listed as NA, masking as NONE, and the model as SINGLE GROUP. As a result, the record does not describe a randomized comparison with a control group receiving another treatment or no irradiation.
Primary question
The primary outcome was progression-free survival, with a timeframe of up to 5 years. The clinical question was whether the study could assess progression-free survival after prophylactic liver irradiation in this higher-risk population. The study terminated early, and the registry states that no analysis was conducted and no data were collected for this outcome measure.
3. Trial Design
This was a single-group interventional study of prophylactic hepatic irradiation for uveal melanoma. The registry lists phase as NA, allocation as NA, and masking as NONE. There was no like-for-like control comparison, so the design cannot estimate a treatment contrast against a concurrent comparator group. The registry lists enrollment as 2.
The treatment group is described as receiving external beam radiation therapy. The planned schedule was daily treatment over 20 minutes on Monday-Friday for up to 10 fractions over approximately 2 weeks. Laboratory biomarker analysis was also listed, but the registry does not describe how those analyses were to be conducted or used.
The record gives a study start of 2014-10 and primary completion of 2015-07, and lists the study status as TERMINATED. The primary outcome was progression-free survival over a timeframe of up to 5 years. The record explains that participants would need to be followed for that duration to answer the objective, but the reported follow-up was 5 months for subject 1 and 2 months for subject 2. It states that the study terminated early and no analysis was conducted for this outcome.
The registry lists seven outcome measures in total. Secondary outcomes include acute and late toxicity assessed using NCI CTCAE Version 4, overall survival, distant failure rates, and disease-specific survival. The record does not provide an analysis plan or outcome estimates for these measures. The sponsor is listed as Jonsson Comprehensive Cancer Center.
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
| Stage | Treatment (External Beam Radiation Therapy) |
|---|---|
| STARTED | 2 |
| COMPLETED | 2 |
| NOT COMPLETED | 0 |
Analysis population for the primary outcome, as defined in the registry: Study terminated early no analysis conducted. Subjects would need to be followed for up to 5 years to answer this objective. Subject 1 was followed 5 months and subject 2 was followed 2 months. Therefore, data was not collected from any subject for this Outcome Measure.
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.
Population: only two subjects were enrolled
| Characteristic | Unit | Treatment (External Beam Radiation Therapy) |
|---|---|---|
| Participants analysed | 2 | |
| Age, Categorical: <=18 years | Participants | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 2 |
| Age, Categorical: >=65 years | Participants | 0 |
| Sex: Female, Male: Female | Participants | 1 |
| Sex: Female, Male: Male | Participants | 1 |
| Region of Enrollment: United States | participants | 2 |
6. Primary Endpoint
The registry lists the primary outcome as Progression-free Survival, measured over Up to 5 years.
| Element | Registry entry |
|---|---|
| Result type | N/A |
| Measure of spread | not applicable |
| Unit | not stated |
| Endpoint classification | not reduced to a single comparison |
Progression-free survival was the primary endpoint, with follow-up planned for up to 5 years. In general, a time-to-event endpoint records the time until a prespecified event occurs. It can describe how long participants remain without the event under study while accounting for differences in follow-up duration. The precise events defining progression-free survival in this study are not described in the registry record, so the operational endpoint definition cannot be reconstructed from the record alone.
Researchers use progression-free survival because it can capture disease progression over time rather than only recording whether progression has occurred at a single visit. That makes it important to define the event, start point, assessment schedule, and rules for incomplete follow-up in advance. Those details are not reported in the registry record.
For this trial, the endpoint has no reported result. The record says that subjects would need follow-up for up to 5 years, but subject 1 was followed for 5 months and subject 2 for 2 months. It further states that data were not collected from any subject for this outcome measure and that no analysis was conducted. Consequently, the record supplies no progression-free survival estimate, event count, or uncertainty interval to interpret.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The central statistical fact is that the planned primary outcome was not analyzed. The registry states that the study terminated early, that no analysis was conducted, and that data were not collected from any subject for the progression-free survival outcome. The follow-up recorded for subject 1 and subject 2 was shorter than the endpoint's stated timeframe of up to 5 years. Thus, the record does not establish an observed progression-free survival result, whether favorable or unfavorable.
The enrollment listed is 2, and the design is single-group. Even if an outcome estimate had been reported, the absence of a concurrent comparator would limit conclusions about whether any observed outcome was caused by irradiation rather than other influences. A single-group study can describe outcomes in the treated group, but separating treatment effects from patient characteristics, the natural course of disease, or other care requires additional design assumptions. The registry does not report a causal analysis or adjustment strategy.
There are no primary endpoint estimates from which to assess statistical precision. A confidence interval, in general, expresses the range of values compatible with the data under a specified statistical procedure. Here, the record reports no progression-free survival estimate and no interval, so readers cannot judge the amount of uncertainty around a treatment effect or an event-time estimate. This is different from a finding of no effect: the registry reports that the endpoint was not analyzed, not that an analysis found no difference.
The serious and other adverse event figures are also limited to the registry's reported counts. For the treatment group, the record lists 2 at risk and 0 affected for serious adverse events, and 2 at risk and 0 affected for other adverse events. These are descriptive safety entries, not a comparative safety analysis. They do not establish the absence of risk, particularly without information about assessment completeness, event definitions beyond the listed CTCAE outcomes, or longer observation. The deaths field has no reported value.
Overall, the registry documents the intended question and the early termination, but it does not provide an efficacy estimate. Any interpretation should preserve the distinction between an unmeasured or unanalyzed endpoint and a measured endpoint that shows a particular result.
9. Statistical Methods Explained
What can be learned from a single-group design?
The registry identifies a SINGLE GROUP model and no comparator. In general, a single-group design can describe treatment delivery and outcomes among participants who receive the intervention. It cannot by itself provide a direct estimate of how outcomes would have differed under an alternative treatment or no treatment. When a study aims to assess a treatment effect, a concurrent comparator helps distinguish effects associated with treatment from changes that might occur for other reasons. That contrast is absent from this record.
Allocation is listed as NA, and masking as NONE. Those entries do not describe a random allocation process or blinded assessment. The record does not report a protocol-level explanation of the allocation entry, nor does it describe safeguards against ascertainment or assessment bias. The absence of a comparator is the primary design constraint for interpreting any treatment effect, even if outcome data had been available.
How is a time-to-event outcome usually analyzed?
In general, time-to-event analysis uses both the timing of events and the length of observation. Participants who have not experienced the event by their last observation may contribute censored follow-up: the analysis uses their observed time without treating them as known to remain event-free indefinitely. Common approaches include survival curves and regression models, but the registry does not report that any particular method was planned or used in this trial. It reports no analysis for progression-free survival.
These methods rely on a defined event and appropriate follow-up information. The registry gives progression-free survival as the endpoint and states a timeframe of up to 5 years, but it does not specify which events counted as progression, how assessments were scheduled, or how censoring would be handled. Without those details and without collected endpoint data, a reader cannot reproduce or evaluate a time-to-event analysis.
What do estimates and confidence intervals ordinarily convey?
In general, an estimate is a numerical summary of the observed data, while a confidence interval conveys statistical uncertainty around that estimate under an analysis method. The interval does not remove limitations in study design or guarantee that the estimate is unbiased. A narrow interval can still reflect a systematically biased comparison, and a wide interval can signal substantial imprecision. No primary endpoint estimate or confidence interval is reported in this registry record, so those principles cannot be applied to an efficacy result for this study.
Why does over-dispersion matter in some analyses?
In general, over-dispersion occurs when count data vary more than a model assumes. If a model assumes less variation than is present, standard errors can be too small and confidence intervals can be too narrow. Analysts may use methods that allow extra variation when the outcome and design warrant it. The registry does not report a count-based primary endpoint, an over-dispersion assessment, or a statistical model for the study. This concept therefore explains a general modeling issue; it does not describe an analysis conducted in this trial.
What can the enrollment and follow-up support?
The registry lists enrollment as 2 and reports follow-up of 5 months for subject 1 and 2 months for subject 2. The primary outcome's timeframe is up to 5 years, and the record explicitly states that no data were collected for that measure. These registry entries do not support an estimate of progression-free survival or a stable comparison of outcomes. They also do not permit an inference that an unobserved event did or did not occur after the recorded follow-up.
The registry's sample-size assumptions describe a planning illustration based on an observed effect, with a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. Time-to-event planning is described in terms of total events; other planning is described in participants per arm. These are planning assumptions, not an analysis of this single-group study. The record does not report a study-specific sample-size justification, and an illustration based on an observed effect is not observed power or evidence that the trial could answer its primary question.
In general, a planned sample size is selected to target a specified precision or chance of detecting an effect under assumptions. Such calculations depend on the design, endpoint, effect size, event rate or variability, and analysis method. Planning values are not observed outcomes, and they do not compensate for missing endpoint data or an absent comparator. The registry provides no primary outcome effect estimate on which to base an efficacy interpretation.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists seven outcome measures, including progression-free survival as the primary outcome and several secondary outcomes. When multiple outcomes are tested, the chance of obtaining at least one apparently unusual result can increase if each is assessed separately without a prespecified strategy. In general, multiplicity can be addressed through a testing hierarchy, adjusted significance thresholds, or a clear distinction between confirmatory and exploratory outcomes. The registry record does not report a multiplicity strategy, a hierarchy among secondary outcomes, or a statistical analysis plan.
The record reports zero analyses and states that no analysis was conducted for the primary outcome. It also says that data were not collected from any subject for that outcome measure. The recorded follow-up durations were 5 months for subject 1 and 2 months for subject 2, while the endpoint timeframe was up to 5 years. These statements indicate that a primary endpoint analysis is unavailable; they should not be recast as an analysis with a null result.
The registry does not report an analysis population, rules for inclusion or exclusion, an intention-to-treat definition, or a per-protocol definition. It also does not report methods for handling missing data, censoring rules, imputation, or withdrawals. Those details matter because analysis choices can affect which observations contribute and how uncertainty is represented. In the absence of an analysis and these methods, there is no basis for reconstructing an analysis population or quantifying the impact of incomplete follow-up.
The registry does not specify whether any interim analyses were planned or conducted. It also does not report a sample-size justification. These omissions leave the decision framework and the intended inferential safeguards unclear, but they do not alter the key point: the primary outcome is not reported as analyzed.
11. Safety Results
The registry reports serious adverse events as affected participants divided by participants at risk.
| Arm | Participants with serious adverse events | Participants at risk | Percentage |
|---|---|---|---|
| Treatment (External Beam Radiation Therapy) | 0 | 2 | 0.0% |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 0% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Treatment (External Beam Radiation Therapy) | 0 of 2 |
For the treatment group, the registry lists 2 at risk and 0 affected for serious adverse events. It also lists 2 at risk and 0 affected for other adverse events. The serious adverse event terms list is empty. These entries describe what was recorded in the registry; they are not proof that no adverse effects occurred or that treatment is free of risk.
The record lists acute and late toxicity as secondary outcomes assessed under NCI CTCAE Version 4, but it does not provide detailed toxicity results or explain the completeness and duration of safety assessments. The deaths field has no reported value. A blank or unavailable field should not be read as a zero count.
In general, safety counts depend on who was assessed, how events were defined, and how long observation continued. The registry's follow-up information is limited, and the study terminated early. Without fuller reporting of event ascertainment and follow-up, the adverse-event entries should be interpreted narrowly as registry counts rather than as a comprehensive estimate of safety.
12. What the Result Does, and Does Not, Mean
The record documents an intended study of liver-directed external beam radiation therapy in people with uveal melanoma described as having monosomy 3 or DecisionDx Class 2 disease. It specifies a single-group design, the planned treatment schedule, and progression-free survival as the primary outcome over up to 5 years. It also records that the study terminated early.
What the record does not establish is whether prophylactic irradiation changes progression-free survival. There is no reported primary endpoint analysis, no endpoint data collected according to the registry description, and no comparator group. Therefore, the record does not support a conclusion that the intervention improved, worsened, or had no effect on progression-free survival. Lack of an analyzed result is not evidence of no effect.
The safety entries are limited descriptive counts: the registry lists 0 serious adverse events and 0 other adverse events among 2 at risk in each category. Those entries do not establish that there were no harms, because the record does not describe complete ascertainment or provide detailed safety follow-up. The deaths field has no reported value and should not be treated as a zero.
In general, a treatment-effect claim needs an appropriate comparison and outcome data that are sufficiently complete for the stated question. This trial's design lacks a concurrent comparator, and its primary endpoint was not analyzed. The registry is therefore informative about the study's plan and termination, but it cannot answer the intended efficacy question. Any broader clinical conclusion would go beyond what the record reports.
13. Why This Trial Matters Statistically
This trial matters statistically because it illustrates the difference between a registered research question and an answer supported by analyzed data. The record names a primary time-to-event outcome and a follow-up horizon of up to 5 years, yet it also states that the study terminated early and no analysis was conducted. A clearly specified endpoint does not itself produce an estimate; the analysis requires relevant outcome observations and a defined method.
It also illustrates how design affects interpretation. The registry lists a single-group model with no comparator. A single-group study can document treatment delivery and observed events, but it does not provide the direct between-group contrast needed to assess whether outcomes differ under treatment versus an alternative. This limitation would remain even if descriptive outcome data were available.
The short follow-up reported for subject 1 and subject 2 is especially relevant to a time-to-event objective stated over up to 5 years. In general, inadequate follow-up can leave event-time outcomes unresolved and limit the information available for estimation. Here, the registry goes further and explicitly says no data were collected for the primary outcome.
Finally, the safety counts show why registry entries need context. A zero count is a description of reported events, not a guarantee of complete assessment or evidence of no risk. Read together, the design and outcome record demonstrate why statistical interpretation must distinguish study intent, data collection, analysis, and causal evidence.
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 important trial-specific limitation is that the study terminated early and the primary endpoint was not analyzed. The registry states that data were not collected from any subject for progression-free survival. Follow-up was 5 months for subject 1 and 2 months for subject 2, while the endpoint timeframe was up to 5 years. The intended time-to-event question therefore has no reported estimate in this record.
The design is single-group, with allocation listed as NA and no comparator arm. The study consequently cannot provide a direct comparison against an alternative intervention or usual care. No masking was used, which may also matter for outcome assessment, although the registry does not describe assessment procedures or whether the endpoint involved subjective judgments.
Several details needed to evaluate methods are not reported in the registry record. These include the operational definition of progression-free survival, the statistical analysis plan, the analysis population, censoring and missing-data rules, multiplicity handling, and the sample-size justification. The record does not report whether interim analyses were planned or conducted. These omissions prevent readers from assessing the intended inferential procedures beyond the basic design description.
The safety data are limited to the reported adverse-event counts and do not include detailed event terms or a reported value for deaths. The registry's listed secondary outcomes are not accompanied by reported analyses. Together, these limitations mean the record describes the study's aim and status, but does not provide a basis for estimating efficacy or drawing a comprehensive safety conclusion.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Radiation Therapy in Preventing Liver Metastases in Patients With Uveal Melanoma Who HaveMonosomy 3 or DecisionDx Class 2 Disease and Are More Likely to Develop Liver Metastases — NCT02336763.
- Registry record last updated 2020-07-24; status last verified 2016-03.
- Results first posted 2016-03-11.
- 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.
Continue through the Clinical Biostats statistical pathway
Use this trial's endpoint as a starting point for deeper study of effect measures, confidence intervals, and sample-size planning.
18. Record Summary
The registry record describes a single-group study of prophylactic hepatic irradiation in people with uveal melanoma and higher-risk markers. The treatment was external beam radiation therapy, with a planned schedule of daily sessions over 20 minutes on Monday-Friday for up to 10 fractions over approximately 2 weeks. The primary outcome was progression-free survival over up to 5 years.
The study is listed as TERMINATED, with enrollment of 2. The record reports follow-up of 5 months for subject 1 and 2 months for subject 2, states that no analysis was conducted, and says no data were collected for the primary outcome. It provides no efficacy estimate or comparator-based treatment effect. Serious and other adverse event counts are listed as 0 affected, with 2 at risk in each category; the deaths field has no reported value.