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 Combination of SBRT With Sequential S-1 for Treating Locally Advanced Pancreatic Cancer (NCT02704143), a na na study. The primary outcome is One-year Overall Survival Rate.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT02704143 |
| Phase | NA |
| Condition | Pancreatic Cancer |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 63 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Changhai Hospital |
| Results posted | Yes |
2. Clinical Question
Population
Patients with locally advanced pancreatic cancer and poor medical conditions. The registry record does not report the primary outcome population separately.
Intervention
Combination of Cyberknife, a form of stereotactic body radiation therapy (SBRT), with sequential S-1.
Comparator
There is no comparator group in the single-group design. The registry record does not report a control arm.
Primary question
What was the one-year overall survival rate among enrolled participants, defined as the proportion surviving more than 1 year?
The registry record describes a study of the safety and efficacy of the combination in patients with locally advanced pancreatic cancer and poor medical conditions. Its primary endpoint is a fixed-time survival measure, rather than a comparison between treatment groups. The central statistical question is therefore descriptive: what proportion of the enrolled group survived beyond the one-year landmark, and how precise is that estimate?
The record identifies the intervention as combination of Cyberknife with S-1 and describes S-1 as sequential. It does not provide further details about treatment delivery or the specific patient characteristics included under poor medical conditions. The record also names acute and late toxicities following SBRT, progression-free survival, quality of life, and overall survival among its secondary outcomes.
Because the trial has no control group, its results cannot directly quantify how outcomes compare with another treatment or with no study intervention. The registry record does not report the primary survival result, so the clinical question can be described, but the answer cannot be determined from the posted registry information.
3. Trial Design
This is a completed, single-group clinical trial registered as NCT02704143. The registry lists an enrollment of 63 and identifies Changhai Hospital as the sponsor. The study start is recorded as 2016-02, and primary completion is recorded as 2020-05. The current status is COMPLETED.
The intervention is described as combination of Cyberknife with S-1. The title and official title describe stereotactic body radiation therapy with sequential S-1 for patients with locally advanced pancreatic cancer and poor medical conditions. The arm description states that eligible patients will receive the combination. No separate control arm is listed.
The design metadata identify the study model as single group, with allocation recorded as NA and masking as none. The phase field is recorded as NA, although the official title calls the study a phase II clinical trial. These are different pieces of registry information: the title describes the trial as phase II, while the structured phase entry does not report a phase.
The primary outcome is one-year overall survival rate, defined in the registry as the ratio of participants surviving more than 1 year to the total enrolled. The listed secondary outcomes cover acute and late toxicities following SBRT, median progression-free survival, quality of life, and median overall survival. The registry lists six outcome measures, but the posted information does not include numerical results for the primary endpoint or analyses for it.
A single-group study can describe outcomes among participants who received the intervention, but it does not provide a concurrent treatment comparison. The registry record does not report a randomized allocation process, and the study is explicitly not a randomized comparison. Results from this design should be interpreted as observations within the enrolled group, not as an estimate of a difference between treatments.
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.
Before assignment: There were significant events that occur after participant enrollment, but prior to assignment of participants to an arm or group.
Overall Study
| Stage | Combination of Cyberknife With S-1 |
|---|---|
| STARTED | 63 |
| COMPLETED | 53 |
| NOT COMPLETED | 10 |
Reasons for not completing this period:
| Reason | Combination of Cyberknife With S-1 |
|---|---|
| disease progression | 10 |
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: Patients were enrolled according to the inclusion and exclusion criteria. All patients received follow-ups and were included in the final analysis.
| Characteristic | Unit | Combination of Cyberknife With S-1 |
|---|---|---|
| Participants analysed | 63 | |
| Age, Categorical: <=18 years | Participants | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 11 |
| Age, Categorical: >=65 years | Participants | 52 |
| Age, Continuous | years | 76.0 (71.5 to 81.0) |
| Sex: Female, Male: Female | Participants | 27 |
| Sex: Female, Male: Male | Participants | 36 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 |
| Race (NIH/OMB): Asian | Participants | 63 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 |
| Race (NIH/OMB): Black or African American | Participants | 0 |
| Race (NIH/OMB): White | Participants | 0 |
| Race (NIH/OMB): More than one race | Participants | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 0 |
| Region of Enrollment: China | participants | 63 |
6. Primary Endpoint
The registry lists the primary outcome as One-year Overall Survival Rate, measured over 1 year.
| Element | Registry entry |
|---|---|
| Result type | Count Of Participants |
| Measure of spread | not applicable |
| Unit | Participants |
| Endpoint classification | Binary Endpoint |
The primary endpoint is the one-year overall survival rate. The registry defines it as the number of participants surviving more than 1 year divided by the total number of participants enrolled. It is a binary, fixed-time summary: each participant is counted according to whether they survived beyond the stated landmark.
As a general statistical concept, a fixed-time survival proportion gives a clinically interpretable snapshot at a specified point in follow-up. It can be easier to understand than a summary of the entire time-to-event experience. However, it does not describe when deaths occurred before the landmark, nor does it distinguish participants with substantially different survival times after it. Time-to-event analyses can use more of the timing information, subject to their assumptions and the availability of follow-up data.
The registry record does not report the number of participants who survived beyond 1 year, the resulting rate, or an uncertainty interval for that rate. It also does not report how participants whose one-year status was unknown were handled. Accordingly, the endpoint definition is available, but its observed value and precision are not reported in the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry describes a single-group study of Cyberknife with sequential S-1 and lists one-year overall survival as the primary endpoint. The endpoint definition is clear enough to identify the intended summary: the proportion of enrolled participants who survived more than 1 year. The posted record does not provide the numerator, the calculated rate, or an uncertainty interval. It therefore does not establish what the observed one-year survival result was or how precisely it was estimated.
The record lists an enrollment of 63. That figure describes enrollment, not the number known to have a one-year outcome. The registry does not report how many participants had complete follow-up to the landmark, whether any outcome information was missing, or how incomplete follow-up was addressed. The enrollment figure alone cannot be used to recover the survival rate.
The design also limits the interpretation of any outcome that might be reported elsewhere. With one group and no control arm, an outcome describes the enrolled participants receiving the combination, but it cannot by itself show how outcomes would have differed under another approach. Differences in patient characteristics, the course of disease, other care, and follow-up could influence observed outcomes; the registry record does not provide information to separate those influences from the intervention.
The registry lists secondary outcomes concerning acute and late toxicities following SBRT, progression-free survival, quality of life, and overall survival. Those outcome descriptions indicate what the study intended to assess, not what it found. Numerical results for these outcomes are not reported in the registry record. The record also lists no analyses, so it does not provide estimates, hypothesis tests, or uncertainty measures to interpret.
The adverse-event information lists 6 participants with serious adverse events and 0 with other adverse events, with 63 participants at risk for each entry. A serious adverse event count is not interchangeable with a count of all adverse events or a measure of treatment effect. The record lists nausea and vomitting as the top serious term at 9.5%, but does not explain its relationship to the participant-level serious-event count. It also lists 63 under deaths in the adverse-event group; the registry record does not explain that entry or how it relates to the primary survival endpoint. It should not be treated as a reported one-year survival result.
Overall, the posted information supports a description of the trial design, endpoint definition, and selected adverse-event entries. It does not support a conclusion about the size or precision of the primary survival result. Any interpretation of outcomes as comparative or causal would exceed what this single-group registry record reports.
9. Statistical Methods Explained
The registry record identifies a binary primary outcome and a single-group design, but reports no outcome analyses. General statistical concepts can clarify what would be needed to interpret such an endpoint; they do not supply a missing trial result.
What does a binary survival endpoint represent?
A binary endpoint classifies each participant into one of two outcome categories at a defined landmark. For this trial, the registry defines success for the endpoint as surviving more than 1 year. A proportion would require both a count meeting that definition and an appropriate denominator. The registry describes the denominator as the total number enrolled, but does not report the count surviving beyond the landmark or the observed proportion. Enrollment by itself is not enough to determine the result.
For a proportion to be interpretable, the handling of participants without known status at the landmark matters. If all enrolled participants have ascertainable status, the enrolled group can serve as the denominator described in the registry definition. If some statuses are unknown, excluding those participants, counting them as not surviving, or using a time-to-event method can lead to different summaries. The registry record does not report missing-status handling, so none of these approaches can be attributed to the trial.
Why report uncertainty as well as an estimate?
As a general explanation, a confidence interval describes the range of values reasonably compatible with the observed data under a statistical method and its assumptions. It helps readers judge precision: a point estimate alone does not show how much uncertainty accompanies it. A confidence interval is not a guarantee that the true value lies within the interval, and it does not resolve limitations in the design or data. No confidence interval or primary endpoint estimate is reported in the registry record.
For a single proportion, uncertainty depends on the observed outcome count and the method used to calculate the interval. Methods can behave differently when data are sparse or an estimate is near a boundary. Since neither the outcome count nor an analysis method is reported, a particular interval method cannot be assessed for this trial.
What can a one-group analysis establish?
A one-group analysis can describe the outcomes observed among the enrolled participants. It cannot calculate a treatment-versus-control contrast when no control group is present. General causal interpretation requires a credible basis for estimating what would have happened to comparable participants under an alternative condition. The registry record does not report such a comparison. Even a precisely estimated proportion in the treated group would remain a descriptive result, rather than a direct estimate of a treatment effect against a comparator.
The registry identifies no analyses. It does not report a statistical model, an estimation method, a hypothesis test, or an adjustment strategy. Thus, there is no basis for attributing an unreported model or inferential procedure to the investigators. The primary endpoint is a fixed-time survival proportion, while the secondary outcome descriptions include median progression-free survival and median overall survival. Those time-to-event summaries require different information from a single binary landmark outcome, including event times and follow-up or censoring information; the registry record does not report their analysis details.
How should planning illustrations be read?
The record describes sample-size assumptions for planning illustrations based on an observed effect, with a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. It specifies that an effect to detect is a stated fraction of the observed effect. These are described as planning assumptions, not the trial's own design justification or an observed-power calculation.
Those assumptions describe a hypothetical two-arm planning framework, whereas this trial is recorded as single group with no like-for-like control comparison. Such illustrations should not be mistaken for the actual allocation, analysis, or design of this trial. The registry record does not report the protocol's sample-size justification, the observed effect used for planning, or a trial-specific power calculation. Any sample-size illustration is a planning aid, not evidence that the trial had a particular probability of detecting an effect or that its result is precise.
Over-dispersion is a general concern when count data vary more than a chosen model expects. It is not a substitute for defining the endpoint or reporting the analysis. The primary endpoint is described as a participant count used to form a proportion, and no model or dispersion estimate is reported. There is therefore no reported over-dispersion assessment to interpret.
10. Exact Estimates for Each Arm
No two-arm comparison is shown for this trial, but each arm's result can still be summarized with exact interval estimates computed from the posted counts. The Clopper-Pearson interval is exact and conservative; the Wilson interval is a common closer-to-nominal alternative; the Bayesian credible interval uses a uniform Beta(1, 1) prior. For small groups the three can differ noticeably.
| Arm | Participants | Events | Observed % | Clopper-Pearson 95% CI | Wilson 95% CI | Bayesian 95% credible interval |
|---|---|---|---|---|---|---|
| Combination of Cyberknife With S-1 | 63 | 46 | 73.0% | 60.3% to 83.4% | 61.0% to 82.4% | 60.9% to 82.4% |
R code and output
arm <- c("Combination of Cyberknife With S-1")
n <- c(63)
events <- c(46)
for (i in seq_along(n)) {
ci <- binom.test(events[i], n[i])$conf.int # Clopper-Pearson exact interval
cr <- qbeta(c(0.025, 0.975), 1 + events[i], 1 + n[i] - events[i]) # Bayesian, uniform Beta(1,1) prior
wi <- (function(x, n) { p <- x / n; z <- qnorm(0.975); d <- 1 + z^2 / n
c((p + z^2 / (2 * n) - z * sqrt(p * (1 - p) / n + z^2 / (4 * n^2))) / d, (p + z^2 / (2 * n) + z * sqrt(p * (1 - p) / n + z^2 / (4 * n^2))) / d) })(events[i], n[i])
cat(sprintf("ARM|%s|%d|%d|%.1f|%.1f|%.1f|%.1f|%.1f|%.1f|%.1f\n", arm[i], n[i], events[i], 100 * events[i] / n[i],
100 * ci[1], 100 * ci[2], 100 * wi[1], 100 * wi[2], 100 * cr[1], 100 * cr[2]))
}
ARM Combination of Cyberknife With S-1 63 46 73.0 60.3 83.4 61.0 82.4 60.9 82.411. Multiplicity, Missing Data and Analysis Populations
The registry lists six outcome measures: one primary outcome and five named secondary outcomes. The primary measure is one-year overall survival. The secondary outcomes address acute and late toxicities following SBRT, median progression-free survival, quality of life, and median overall survival. Considering multiple outcomes can raise the possibility of chance-positive findings when many statistical tests are conducted. Whether and how to address that issue depends on the prespecified analysis plan and the inferential claims being made.
The registry record does not report a multiplicity strategy, such as an adjustment to significance thresholds, a hierarchy for testing outcomes, or a distinction between confirmatory and exploratory analyses. It also lists no analyses. It is therefore not possible to determine whether statistical tests were conducted or how any multiplicity was handled. The outcome list should be read as a list of measures, not as evidence that each was analyzed or that any result was statistically significant.
Missing-data handling is also not reported. For the primary endpoint, the record does not say whether one-year status was available for every enrolled participant or how unknown status would be treated. The registry does not describe imputation, exclusions, censoring rules, or sensitivity analyses. These details matter because the way missing outcome information is handled can affect both an estimate and its uncertainty.
The primary outcome's population entry is blank, and the registry does not define an analysis population separately from the enrolled group. It does not report whether any participants were excluded from an analysis or whether the analysis followed a particular population principle. Consequently, the enrolled population and the population used in any outcome analysis cannot be confirmed as identical from the registry record.
12. 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 |
|---|---|---|---|
| Combination of Cyberknife With S-1 | 6 | 63 | 9.5% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Combination of Cyberknife With S-1 | 63 of 63 |
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 |
|---|---|
| Combination of Cyberknife With S-1 | 0 of 63 |
Most frequent serious adverse event terms
| Event term | Organ system | Combination of Cyberknife With S-1 |
|---|---|---|
| nausea and vomitting | Gastrointestinal disorders | 6 of 63 |
Serious events with the highest arm-level rate: nausea and vomitting (9.5%).
The adverse-event entry for the Combination of Cyberknife With S-1 group lists 63 participants at risk for serious adverse events and 6 participants with serious adverse events. It lists 63 at risk and 0 participants with other adverse events. These are participant counts; they do not describe the number of events per participant, their severity distribution, or the timing of events.
The record identifies nausea and vomitting as the top serious term and gives 9.5%. It does not clarify how this term-level percentage relates to the 6 participants with serious adverse events, or specify the denominator and counting convention for that percentage. It should therefore be read as a registry-listed term and percentage, not as a percentage recalculated from the participant counts.
The same adverse-event entry lists 63 under deaths. The registry record does not explain the meaning or context of this entry, or how it relates to the primary endpoint. It cannot be reconciled from the posted information with the one-year overall survival definition. The primary survival result itself is not reported in the registry record.
These entries do not provide a comparative safety estimate: the trial has no control group, and no statistical analyses are listed. The record also does not report event definitions, attribution procedures, or follow-up details for these safety counts.
13. What the Result Does, and Does Not, Mean
The record establishes that NCT02704143 was a completed single-group study of Cyberknife with sequential S-1 in patients with locally advanced pancreatic cancer and poor medical conditions. It specifies one-year overall survival as the primary endpoint and defines the intended rate using survival beyond 1 year among enrolled participants. It also identifies safety and other clinical outcomes as secondary measures.
What the record does not establish is the observed one-year survival rate. It reports no count of participants surviving beyond the landmark, no calculated rate, and no uncertainty interval. It also provides no analyses. The endpoint definition should not be confused with an endpoint result, and enrollment should not be treated as the number of participants with a known outcome.
Even if a primary result were available, the study's single-group structure would limit what it could say about the intervention relative to another approach. An outcome among participants in one group does not, by itself, estimate what would have happened under a comparator. The record does not report a randomized comparison or another control group.
The adverse-event entries offer some participant counts and a listed serious-event term, but their context is limited. The record does not explain the deaths entry or its relation to the survival endpoint. The listed term percentage also cannot be reconciled with the participant counts from the information recorded. These fields should be interpreted cautiously and not treated as a complete safety analysis.
In short, the registry information describes the research question, design, endpoint definitions, and selected safety entries. It does not provide enough outcome or analysis information to quantify the primary result, its precision, or a comparative effect. Those omissions are boundaries on interpretation, not evidence for either a favorable or unfavorable outcome.
14. Why This Trial Matters Statistically
This trial illustrates the distinction between an endpoint definition and a reported result. The registry defines one-year overall survival in concrete terms, but it does not report the numerator or the rate. A clear definition is necessary for interpretation, yet it cannot replace the observed data needed to estimate the outcome.
It also highlights why design and analysis must be read together. A single-group study can describe what happened among its participants, but has no concurrent comparator for estimating a between-group contrast. The title's phase II wording does not change that design feature, and the structured phase field itself is recorded as NA.
For biostatistical interpretation, precision and completeness matter alongside the point estimate. An uncertainty interval, details about follow-up and missing status, and a defined analysis population would help readers understand how much confidence to place in an estimated survival proportion. The registry record does not report these items for the primary outcome.
The adverse-event entries provide a further lesson in data interpretation: counts, term-level percentages, and a deaths field are not self-explanatory without definitions and context. The record leaves the relationship among these entries unclear. Careful reading means distinguishing what is explicitly recorded from what cannot be inferred, while avoiding a comparative or causal claim that the design and posted analyses do not support.
15. 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 primary limitation for interpretation is the absence of the primary endpoint result. Although the registry defines one-year overall survival and reports enrollment, it does not give the number surviving beyond 1 year, the estimated rate, or an uncertainty interval. The outcome population is not specified separately, and handling of unknown one-year status is not reported.
The single-group design has no like-for-like control comparison. It can describe outcomes in the enrolled group but cannot directly estimate a difference against another treatment or establish that observed outcomes were caused by the intervention. The record also does not report analyses, so statistical methods and inferential choices cannot be evaluated.
The registry's phase information is not fully aligned: the official title calls the study phase II, while the structured phase entry is NA. This does not alter the recorded single-group design, but it limits what can be stated from the phase field. The record does not report the protocol's sample-size justification, an interim-analysis plan, or a detailed statistical analysis plan.
Safety information is limited by unclear context. The serious and other adverse-event participant counts are listed, along with a term-level percentage and a deaths entry, but the record does not explain how those fields relate to one another or to the primary survival outcome. Outcome definitions and analysis details for the secondary measures are also not reported. These limitations prevent a fuller assessment of outcome completeness, precision, and the meaning of the posted safety entries.
16. Related Tutorials
17. Related Statistical Calculators
18. Sources
- ClinicalTrials.gov: Combination of SBRT With Sequential S-1 for Treating Locally Advanced Pancreatic Cancer — NCT02704143.
- Registry record last updated 2020-10-19; status last verified 2020-08.
- Results first posted 2020-07-17.
- 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.
19. Record Summary
NCT02704143 is a completed single-group study sponsored by Changhai Hospital, with enrollment listed as 63. Its start is recorded as 2016-02 and primary completion as 2020-05. The official title describes a phase II clinical trial, while the structured phase entry is NA.
The intervention combines Cyberknife SBRT with sequential S-1 for patients with locally advanced pancreatic cancer and poor medical conditions. The primary endpoint is one-year overall survival, defined as the proportion of enrolled participants surviving more than 1 year. Five secondary outcomes are named, including toxicity, progression-free survival, quality of life, and overall survival measures.
The registry record does not report the primary survival result or any analyses. It lists 6 participants with serious adverse events, 0 with other adverse events, a serious term of nausea and vomitting at 9.5%, and 63 under deaths; the relationship and context of those entries are not explained. The single-group design does not provide a control comparison.