Radiation Therapy and Intratumoral Autologous Dendritic Cells in Soft Tissue Sarcomas (STS): Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Radiation Therapy and Intratumoral Autologous Dendritic Cells in Soft Tissue Sarcomas (STS) (NCT01347034), a non-randomized phase 2 study. The primary outcome is Number of Participants With Enhanced T Lymphocyte Immune Response Specific for Soft Tissue Sarcoma Tumor Associated Antigens(STS-TAAs).

2. Clinical Question

This question is about an immune response measured in laboratory assays, not a direct measure of tumor shrinkage, disease control, or survival. The outcome definition combines assay thresholds with comparisons against control stimuli and the participant’s baseline response. A participant was considered a responder if the criteria were met at any time point, according to the description.

The study compared a radiation-only arm with an arm combining radiation and dendritic cell injection. Because allocation was non-randomized, the comparison cannot by itself establish that any difference in immune response was caused by adding dendritic cells. Differences between the groups may also reflect their clinical or institutional contexts. The registry does not report the primary response counts or an adjusted comparison, so the central clinical question cannot be answered from the posted results.

3. Trial Design

This was a Phase II, parallel, non-randomized study listed as completed. The registry describes an enrollment of 20. Masking is recorded as none. The sponsor was H. Lee Moffitt Cancer Center and Research Institute. The record lists soft tissue sarcoma as the condition and describes the study population as patients with high-risk soft tissue sarcomas.

The active comparator arm received external beam radiation therapy and is identified with the University of Florida. The experimental arm received external beam radiation therapy plus autologous dendritic cell injection and is identified with Moffitt Cancer Center. The primary outcome description refers to an intensified radiation regimen consisting of conventional radiation with a high-dose hypofractionated boost, alongside dendritic cell administration. The registry does not give specific radiation doses or further operational details of treatment administration.

Allocation was not randomized. The registry explicitly notes that the arms are not a like-for-like control comparison. The different center affiliations are relevant context when interpreting arm differences: treatment assignment and study setting are linked in the arm descriptions, and the record does not describe a design that separates center effects from treatment effects. No causal interpretation of an arm contrast is warranted from these details alone.

The primary outcome was the number of participants with an enhanced T lymphocyte immune response specific for soft tissue sarcoma tumor-associated antigens, assessed over 11 weeks per participant. The registry also lists an outcome concerning treatment-emergent serious adverse events and adverse events. It lists two outcome measures and no analyses. Primary endpoint counts, an effect estimate, and an inferential comparison are not reported in the registry record.

The registry lists the study start as 2011-01 and primary completion as 2013-08, with status completed. These dates describe the record’s study timeline; they do not supply missing outcome results. Details about the rationale for the enrollment target, recruitment, follow-up completeness, and statistical analysis plan are not reported in the registry record.

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

Analysis population for the primary outcome, as defined in the registry: All participants

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: All participants

6. Primary Endpoint

The registry lists the primary outcome as Number of Participants With Enhanced T Lymphocyte Immune Response Specific for Soft Tissue Sarcoma Tumor Associated Antigens(STS-TAAs), measured over 11 weeks per participant.

The primary endpoint counts participants whose laboratory tests met the study’s definition of an enhanced T lymphocyte response against soft tissue sarcoma tumor-associated antigens. The observation period is listed as 11 weeks per participant, and the outcome is expressed as a number of participants rather than as a continuous assay measurement.

The response definition uses IFN-γ ELISPOT and proliferation assays. The description requires a response exceeding the stated threshold of 30 spots per 200,000 cells in the IFN-γ ELISPOT assay or 3000 counts/min (CPM) in the proliferation assay. It also requires a response to tumor cell lysates (TCL) or Ad-Surv that is more than 2SD higher than the corresponding control lysate or Ad-c response at the same time point, and more than 2SD higher than the response to the same stimuli at baseline. A participant could qualify at any time point during the stated assessment period.

This endpoint is used to assess whether treatment is associated with a measurable immune response directed at tumor-associated antigens. The threshold and comparison requirements are intended to distinguish a qualifying response from assay background and from the participant’s own baseline. That makes the endpoint a defined immunologic measure, rather than a general clinical outcome.

The registry record does not report how many participants met the criteria, assay-level data, or an arm comparison. It therefore does not show the observed frequency or precision of the primary endpoint. Whether a laboratory response corresponds to a clinical benefit is also not established by this endpoint definition.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The primary outcome is binary at the participant level: each participant either meets the registry’s responder criteria or does not. The outcome is reported as a count of participants with a qualifying immune response. For such an outcome, a complete analysis would ordinarily describe the number meeting the criteria and the denominator assessed in each arm, then present an estimate of the response frequency and its uncertainty. Those primary outcome counts and estimates are not reported in the registry record.

What does a binary endpoint capture?

A binary endpoint reduces assay information to a defined classification. Here, the classification depends on IFN-γ ELISPOT or proliferation assay thresholds and on comparisons with control responses and baseline. This can make a complex laboratory response easier to interpret as a participant-level outcome. It also means that participants with assay values near a threshold may be classified differently from participants with values far from it, even if their underlying immune responses are similar. The record does not provide continuous assay values, so that feature cannot be explored for this study.

The definition allows a qualifying response at any time point during 11 weeks per participant. In general, using repeated observations in this way can identify responses that occur during follow-up, but interpretation depends on how many measurements were planned and actually available, and how missing measurements were handled. Those details are not reported in the registry record. The exact responder criteria are described, but the number of participants tested at each time point is not.

Why does allocation matter?

Random allocation is generally used to make treatment groups comparable, on average, with respect to measured and unmeasured characteristics. This study is explicitly non-randomized. Its arm descriptions associate the radiation-only group with the University of Florida and the radiation-plus-dendritic-cell group with Moffitt Cancer Center. The registry warns that the arms are not a like-for-like control comparison. Thus, a contrast between arms would be vulnerable to confounding: differences could be associated with treatment, center, participant characteristics, or other differences in care and measurement.

In general, statistical adjustment may address some measured differences, but it cannot ensure comparability when important factors are unmeasured or poorly recorded. The registry record does not report an adjusted primary analysis or enough details about participant characteristics to evaluate adjustment. An unadjusted arm comparison would therefore be descriptive, not a secure estimate of a causal treatment effect.

What can a significance test or confidence interval add?

In general, a significance test evaluates how compatible the observed data are with a specified null model; it does not measure the size or importance of an effect. A confidence interval communicates uncertainty around an estimated effect under the assumptions of the analysis. For a binary endpoint, an analysis could compare participant response frequencies or estimate a difference or ratio between groups, but the choice of measure and model should be specified in advance and interpreted in light of the design.

No primary endpoint test, effect estimate, confidence interval, or analysis method is reported in the registry record. The record lists no analyses. It is therefore not possible to evaluate statistical significance, precision, or whether an analysis adjusted for potential differences between the centers or groups. A missing test result is not a negative test result.

How should sample-size illustrations be read?

In general, a sample-size calculation describes how many participants a future study might need under specified assumptions about the effect to detect, significance level, allocation, and statistical method. The record’s planning assumptions specify a two-sided significance level of 0.05, equal allocation, a normal approximation, and an effect defined as a stated fraction of the observed effect. Such calculations are planning illustrations, not evidence about what this study observed, and not observed power. They do not replace a reported treatment-effect estimate or its uncertainty.

The registry record does not report a sample-size justification from the original protocol. The assumptions attached to planning illustrations should not be treated as the trial’s own design rationale. The primary result required to judge an observed effect is not reported in the registry record, so the illustrations cannot supply evidence about the endpoint outcome.

Why can over-dispersion matter?

In general, over-dispersion occurs when outcome variability is greater than a statistical model assumes. It can make standard errors too small if the model does not account for the extra variability, leading to overconfident inferences. The primary endpoint is a participant-level binary outcome, and the registry does not report a model or analysis from which over-dispersion can be evaluated. No conclusion about this issue is warranted for the study’s primary result.

The record also does not describe a multiplicity adjustment, missing-data strategy, or analysis population. Those omissions limit reproducibility and make it difficult to determine how the stated endpoint definition would translate into a final analysis. The available information supports a description of design and outcomes recorded, but not a statistical conclusion about the primary immune-response comparison.

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.

R code and output

arm    <- c("Active Comparator: External Beam Radiation Therapy", "Experimental: External Beam RT + DC Injection")
n      <- c(6, 14)
events <- c(2, 5)
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  Active Comparator: External Beam Radiation Therapy  6  2  33.3  4.3  77.7  9.7  70.0  9.9  71.0
ARM  Experimental: External Beam RT + DC Injection  14  5  35.7  12.8  64.9  16.3  61.2  16.3  61.6

11. Multiplicity, Missing Data and Analysis Populations

The registry lists two outcome measures and no analyses. It identifies the immune-response count as the primary outcome and lists treatment-emergent serious adverse events and adverse events as a secondary outcome. It does not report a statistical analysis plan describing how outcomes were prioritized, how many tests were planned, or whether any adjustment for multiple testing was intended. The effect of multiplicity on the interpretation of inferential results cannot be evaluated because such results are not reported.

Missing-data handling is not reported in the registry record. The primary endpoint is assessed over 11 weeks per participant and permits a qualifying response at any time point, but the record does not state how participants with incomplete assays, missed assessments, or otherwise unavailable endpoint information were classified or included. It also does not report the number of participants with evaluable primary endpoint data by arm.

The analysis population is not reported in the registry record. The endpoint description says the population is all participants, but it does not specify an intention-to-treat, per-protocol, or other analytic definition, or explain how participants who did not complete treatment or assessment were handled. The registry’s enrollment entry does not, by itself, establish which participants contributed to each outcome analysis.

These omissions matter because choices about multiplicity, missing observations, and analysis populations can change the meaning and uncertainty of an estimate. Without the primary response counts and the associated analysis details, the record cannot establish the robustness of an immune-response result or support a statistical comparison between arms.

12. Safety Results

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

Other (non-serious) adverse events

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

Most frequent serious adverse event terms

Most frequent non-serious adverse event terms

Serious events with the highest arm-level rate: anemia (7.1%), dehydration (7.1%).

The registry reports serious adverse events among participants at risk separately by arm. In the external beam radiation therapy arm, 0 of 6 participants at risk had a reported serious adverse event. In the external beam radiation therapy plus dendritic cell injection arm, 1 of 14 participants at risk had a reported serious adverse event. The death field is not reported in the registry record, so it should not be interpreted as a zero count.

For other adverse events, the registry reports 6 of 6 participants at risk in the radiation-only arm and 14 of 14 in the radiation-plus-dendritic-cell arm as affected. The record also lists anemia and dehydration as top serious adverse event terms, each at 7.1%. Arm-specific attribution and additional term-level details are not reported in the registry record.

These are descriptive counts, not a reliable comparative estimate of safety. The study was non-randomized, and the arms were associated with different centers; the registry itself cautions that they are not a like-for-like control comparison. The record does not report a statistical safety analysis, event timing, exposure-adjusted rates, or the clinical context needed to interpret individual events. The counts should therefore be read as what the registry records for each arm, not as evidence that one treatment caused more or fewer events.

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

The record establishes that a Phase II, non-randomized study was conducted to evaluate intensified radiation therapy and intratumoral autologous dendritic cells in high-risk soft tissue sarcoma. It defines a primary laboratory endpoint based on T lymphocyte responses to tumor-associated antigens and records adverse-event counts for the study arms. It does not report the primary immune-response counts or an inferential analysis.

As a result, the posted information cannot show how often participants met the immune-response definition, whether response frequencies differed by arm, or how precisely any such difference was estimated. It also cannot establish that adding dendritic cell injection caused an immune response. The non-randomized allocation and association of arms with different centers further limit causal interpretation.

The primary endpoint is an immunologic measure. Even if a qualifying assay response were reported, it would describe the assay-defined immune response, not by itself a clinical outcome such as tumor control or survival. The registry record does not report those outcomes in the information available for this analysis, so no inference about them follows from the endpoint definition.

The adverse-event counts document events as recorded in the two arms, but they do not provide a controlled comparison. The incomplete reporting of deaths, event details, and analysis methods also constrains interpretation. The registry’s completion status and enrollment entry provide study context, not evidence that the primary endpoint was met or that treatment had a particular effect.

In general, a result can be statistically uncertain even when a point estimate is available, and a statistically clear result would still require consideration of bias, outcome relevance, and design. In this record, the more basic limitation is that the primary result and its uncertainty are not reported. The appropriate reading is therefore descriptive: the trial question and measurement criteria are documented, while the primary effectiveness-related statistical result remains unavailable in the registry record.

14. Why This Trial Matters Statistically

This study raises a useful statistical distinction between a biological measurement and a clinical outcome. The primary endpoint translates laboratory assays into a participant-level responder classification using stated thresholds, control comparisons, and baseline comparisons. That makes the endpoint operationally defined, but it does not make it equivalent to a direct measure of clinical benefit. Interpretation should stay aligned with what the endpoint actually measures.

The non-randomized, center-linked arm structure is also important. A treatment comparison is easiest to interpret when groups are exchangeable apart from the treatment of interest. Here, the registry explicitly cautions that the arms are not a like-for-like control comparison. This makes design context central to statistical interpretation, rather than a minor qualification added after looking at an effect estimate.

The missing primary result illustrates why endpoint definitions and completed-study status are not substitutes for outcome reporting. Without response counts, an effect estimate, and uncertainty, readers cannot assess the magnitude or precision of the primary finding. They also cannot determine whether the observed evidence is compatible with a range of effects.

Finally, safety counts should be distinguished from comparative safety inference. The registry records serious and other adverse events by arm, but the design and the absence of a reported statistical analysis limit comparisons. Descriptive transparency is useful, but it does not resolve causal questions. Together, these features make the record a case study in how design, endpoint construction, and reporting completeness shape what can responsibly be concluded from a clinical trial record.

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 principal limitation is that the primary endpoint result is not reported in the registry record. The record defines the immune-response criteria and assessment period but gives no number of responders by arm, no treatment contrast, and no measure of uncertainty. This prevents evaluation of the main study question.

The non-randomized design limits comparability between groups. The arm descriptions link the radiation-only arm to the University of Florida and the radiation-plus-dendritic-cell arm to Moffitt Cancer Center; the registry warns against treating these as like-for-like controls. Participant characteristics and any adjustment for group differences are not reported in the registry record, so the extent of confounding cannot be assessed.

Further details needed to assess the endpoint are absent. The record does not report how many participants had evaluable assays, how missing or incomplete assessments were handled, or which analysis population was used. The responder definition is described, but assay-level observations and timing of qualifying responses are not reported.

Statistical methods for the primary outcome are not reported, and the registry lists no analyses. The record does not provide an inferential comparison, confidence interval, or multiplicity strategy. Protocol details and the original sample-size justification are also not reported in the registry record. Planning assumptions should not be mistaken for the trial’s own prespecified statistical plan.

Safety reporting is likewise limited to recorded counts and selected serious adverse event terms. Death counts, event timing, severity details beyond the serious/non-serious grouping, and arm-specific attribution for the listed terms are not reported in the registry record. Because of these design and reporting limitations, neither the primary immune-response question nor a comparative safety question can be answered confidently from the posted information.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Radiation Therapy and Intratumoral Autologous Dendritic Cells in Soft Tissue Sarcomas (STS) — NCT01347034.
• Registry record last updated 2016-05-23; status last verified 2016-04.
• Results first posted 2014-08-08.
• 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.

19. Record Summary

The registry record describes a completed Phase II, non-randomized parallel study in high-risk soft tissue sarcoma. The radiation-only arm was associated with the University of Florida, and the radiation-plus-autologous-dendritic-cell arm with Moffitt Cancer Center. The registry cautions that the arms are not a like-for-like control comparison.

The primary endpoint counted participants with an enhanced T lymphocyte response to soft tissue sarcoma tumor-associated antigens during 11 weeks per participant. The response criteria used IFN-γ ELISPOT or proliferation assay thresholds and comparisons with control responses and baseline. The primary endpoint result and statistical analysis are not reported in the registry record.

Serious adverse events were recorded for 0 of 6 participants at risk in the radiation-only arm and 1 of 14 in the combination arm. Other adverse events were recorded for 6 of 6 and 14 of 14, respectively. Death counts are not reported in the registry record. The available information supports a description of the study and recorded safety counts, but not a causal or inferential conclusion about the primary outcome.