Neoadjuvant Chemohormonal Therapy Followed by Salvage Surgery for High Risk PSA: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Neoadjuvant Chemohormonal Therapy Followed by Salvage Surgery for High Risk PSA (NCT01531205), a na phase 2 study. The primary outcome is Surgical Margin Negative Rate (SM Rate).

2. Clinical Question

The clinical question was whether treatment with hormonal therapy and cabazitaxel before salvage surgery could be assessed in people with locally recurrent prostate cancer following radiotherapy. The registry description frames the goal as testing whether adding chemotherapy and hormonal therapy before removal of the prostate would improve the outcome of salvage surgery. However, the single-group design cannot establish the effect of the added pre-operative treatment against a concurrent group receiving a different approach.

The record lists secondary outcomes concerning PSA progression-free survival, complete response, perioperative and postoperative morbidity, and detection of circulating tumor cells. These are distinct questions: some concern disease status or recurrence, while others concern treatment-related events or biological measurements. The record does not report results for these outcomes. It also does not report whether all enrolled participants underwent surgery or contributed data to the primary endpoint.

3. Trial Design

This was a phase 2, single-group study of neoadjuvant chemohormonal therapy followed by salvage surgery. The record lists enrollment as 2 and status as terminated. The study started in 2012-05, with primary completion in 2013-09. The reason for termination is not reported in the registry record.

The experimental arm was titled “Drug and Hormonal Therapy With Salvage Surgery.” Its description includes androgen ablation before surgery, cabazitaxel before surgery, salvage surgery by radical prostatectomy, post-operative hormonal therapy, and post-operative follow-up. The listed interventions also include androgen ablation, cabazitaxel, salvage therapy, neoadjuvant hormonal therapy, and neoadjuvant cabazitaxel.

Masking was listed as NONE, so the registry describes the study as unmasked. Allocation was listed as NA, and the model was SINGLE GROUP. There is no separate control arm described in the record. This means the trial is not a randomized comparison, and its outcomes cannot be interpreted as a direct estimate of the difference between the treatment approach and a concurrent comparator.

The primary endpoint was the percentage of participants with negative surgical margins, assessed one year after surgery. Its stated analysis population was participants who proceeded to surgery. The record lists five outcome measures overall, but no statistical analyses. The number of participants who underwent surgery, the number evaluable for the primary endpoint, and the amount of follow-up achieved are not reported in the registry record.

Single-group studies can describe what happened among enrolled or treated participants. General statistical point: without a concurrent comparison group, observed outcomes cannot separate the effects of the intervention from other explanations, such as participant characteristics, disease course, or changes over time. The trial's small enrollment further limits how precisely any outcome could be estimated, but no endpoint estimate is posted to assess that precision.

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: Participants who proceeded to surgery

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 Surgical Margin Negative Rate (SM Rate), measured over One Year.

The primary endpoint was the surgical margin negative rate, expressed as a percentage of participants. The registry defines a negative or clean margin as one where the pathologist finds no cancer cells at the edge of the tissue removed during surgery. A positive or involved margin means cancer cells are present at that edge. The stated timeframe was one year after surgery, and the endpoint population was participants who proceeded to surgery.

General statistical explanation: a margin status is a binary outcome for an individual—negative or positive—and the rate summarizes the share of the relevant group with a negative finding. This endpoint is used to describe the pathology result after surgery and whether cancer cells were detected at the edge of the removed tissue. It does not, by itself, describe all aspects of subsequent disease course or establish the effect of pre-operative treatment.

The denominator is important: the registry specifies participants who proceeded to surgery, rather than all enrolled participants. The number who had surgery and the number with an evaluable margin result are not reported in the registry record. Nor is the observed margin-negative percentage reported. Consequently, the posted record does not permit interpretation of the primary endpoint's magnitude or precision.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

What kind of outcome was registered?

The primary measure is a percentage of participants with an event, where the event is a negative surgical margin. For each participant with a margin result, the finding is classified as negative or positive. The percentage describes the share of the relevant endpoint population with a negative finding. The registry names that population as participants who proceeded to surgery, not necessarily everyone enrolled.

General statistical explanation: binary outcomes are often summarized by counts and proportions. A proportion is interpretable only when its denominator is clear. Here, the record does not state how many participants proceeded to surgery or had an evaluable margin result, and it does not post the observed percentage. Thus, the definition of the endpoint is available, but its observed value cannot be assessed.

What would a confidence interval add?

General statistical explanation: a confidence interval expresses the uncertainty around an estimated quantity under a specified statistical method. It is not a guarantee that the true value lies within a particular interval, and it does not correct for biases in study design or missing data. For a percentage based on a small group, the interval would generally be important because the estimate may be imprecise. No confidence interval or other uncertainty estimate is reported in the registry record for the primary endpoint.

Because the trial has no posted endpoint estimate, there is no posted interval to interpret. It is therefore not possible to describe the range of values compatible with the trial's primary result or to assess whether the precision would support a firm conclusion.

Why does the study design matter?

The model is SINGLE GROUP, allocation is NA, and there is no separate comparator arm. General statistical explanation: a single-group study can describe outcomes among its participants, but it does not estimate a between-group treatment difference. A before-and-after or historical comparison would require additional information and assumptions; neither is reported in the registry record. The listed design should not be treated as randomized or controlled.

Masking was listed as NONE. General statistical explanation: lack of masking can matter when outcome assessment or participant behavior could be influenced by knowledge of treatment. A surgical margin is a pathology finding, but the registry record does not describe the procedures used to assess or adjudicate it. No additional assumptions about blinding or assessment methods can be made from the entry.

What can the analysis listing establish?

The record lists five outcome measures and 0 analyses. This means the registry entry does not present an analysis result for the primary or secondary outcomes. The number of outcome measures alone does not show that all were measured, that an analysis was completed, or that a particular statistical method was used. The statistical plan, including any hypothesis tests, covariate adjustments, or interim analyses, is not reported in the registry record.

The sample-size assumptions describe a planning illustration based on an observed effect, using a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. The illustration is not the trial's own design justification, and no planning values or calculations for this trial are listed in the record. Because this study has one group and enrollment of 2, the two-arm planning assumptions do not describe its registered design. Any sample-size illustrations should be understood as planning scenarios, not as observed power or evidence about the trial's results.

Why can over-dispersion matter?

General statistical explanation: over-dispersion occurs when observed variability exceeds what a chosen statistical model expects. It can lead to standard errors that are too small if the model does not account for the extra variation. This concept is most relevant to outcomes and models where variability is estimated, such as counts or repeated measurements. The registry does not report a model or analysis for which over-dispersion was assessed. It should not be assumed to have occurred in this trial.

For the primary endpoint, the principal statistical issues visible from the registry are the very small enrollment, an unreported endpoint denominator, and the absence of a posted estimate and uncertainty interval. These prevent quantitative assessment of the margin-negative rate, regardless of which inferential method might otherwise be used.

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("Experimental: Drug and Hormonal Therapy With Salva")
n      <- c(1)
events <- c(1)
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  Experimental: Drug and Hormonal Therapy With Salva  1  1  100.0  2.5  100.0  20.7  100.0  15.8  98.7

11. Multiplicity, Missing Data and Analysis Populations

The registry lists five outcome measures: surgical margin negative rate, PSA progression-free survival, complete response, perioperative and postoperative morbidity, and detection of circulating tumor cells. The margin-negative rate is identified as the primary endpoint; the others are secondary outcomes. However, 0 analyses are listed, and the registry record does not report results for these endpoints.

Multiplicity refers, in general, to the increased chance of at least one false-positive finding when several statistical hypotheses are tested. General statistical explanation: a prespecified analysis plan may address this issue by identifying a primary outcome and specifying how multiple tests will be interpreted or adjusted. The plan for handling multiple outcomes or tests is not reported in the registry record. No adjustment method or hierarchy beyond the primary and secondary outcome labels is stated.

Missing-data handling is also not reported. The record does not say whether participants withdrew, whether any planned assessments were not completed, or how missing endpoint values would be treated. The number who proceeded to surgery and the number with an evaluable margin result are not reported, so the primary endpoint denominator cannot be verified from the entry.

The analysis populations are not described beyond the primary endpoint population of participants who proceeded to surgery. The registry does not report whether analyses were planned for all enrolled participants, treated participants, or another defined group. With enrollment of 2 and no posted analyses, there is no basis for determining the extent or consequences of missing data, or whether outcome analyses followed a prespecified population definition.

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 5% reporting threshold.

Most frequent non-serious adverse event terms

The adverse-event record lists one experimental group, titled “Drug and Hormonal Therapy With Salvage Surgery.” For serious adverse events, 2 participants were at risk and 0 were affected. For other adverse events, 2 participants were at risk and 2 were affected. These figures are descriptive counts for the group, not comparisons between treatment strategies.

The record does not list any top serious adverse-event terms. The deaths field is null, which means a death count is not reported in the registry record; it should not be read as a reported count of zero. The record also does not give event-specific descriptions for the other adverse events, so their types and severity cannot be characterized from the posted figures.

General statistical explanation: “at risk” indicates the group size used for the adverse-event summary, while “affected” counts participants with an event in the stated category. These figures do not necessarily reveal the number of distinct events if one participant could have more than one event. With only 2 participants at risk, the counts are limited descriptions of this group and do not estimate comparative safety against another arm. The record does not report further details about event collection or follow-up duration.

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

The registry entry identifies a small, single-group phase 2 study of hormonal therapy and cabazitaxel before salvage surgery for locally recurrent prostate cancer after radiotherapy. It specifies a primary endpoint—the surgical margin negative rate one year after surgery—and describes the endpoint population as participants who proceeded to surgery. However, the observed primary endpoint result is not reported in the registry record.

Without a reported rate, denominator, or uncertainty estimate, the posted information cannot establish how often negative margins occurred or how precisely that rate was estimated. The secondary outcomes are named, but their results are not reported either. The trial status is TERMINATED, and the reason for termination is not reported.

Even a reported outcome from this design would be descriptive rather than a direct comparison of treatment strategies. The trial has no separate control arm, and its allocation is listed as NA. General statistical explanation: an outcome observed in a single group cannot by itself show what would have happened to comparable participants under a different strategy. The registry entry therefore does not support a causal estimate of the effect of adding pre-operative therapy.

The enrollment of 2 is relevant to interpretation: it is the total listed enrollment, not a stated count of participants who underwent surgery or contributed to the primary endpoint. Those endpoint-specific counts are not reported. The adverse-event figures describe 2 participants at risk, with 0 affected by serious adverse events and 2 affected by other adverse events; details of the latter events are not provided, and deaths are not reported.

These limitations do not establish that the treatment approach is beneficial, harmful, or ineffective. They define what can and cannot be concluded from the registry record: the study's design and intended outcomes are described, but its clinical outcome results and inferential analyses are absent.

14. Why This Trial Matters Statistically

This trial illustrates why a registry's design information and its results must be read separately. The entry describes a clinically specific sequence—hormonal therapy and cabazitaxel before salvage surgery—and defines a pathology-based primary endpoint. Yet the primary endpoint result, its denominator, and any measure of uncertainty are not reported. A clearly defined outcome is not itself evidence about the outcome.

The single-group structure is also central. Without a comparator, an observed margin-negative rate would describe only the participants who underwent surgery. It would not estimate how outcomes differ from another treatment strategy. This is a general design principle: the type of question answered depends on the comparison built into the study, not only on the clinical rationale or endpoint selected.

The enrollment of 2 makes the distinction between a trial's intended question and the information its data can support especially salient. The endpoint population is limited to participants who proceeded to surgery, and the record does not state how many did so. Even a complete count would need careful interpretation because a very small group offers limited precision and limited ability to characterize variation in outcomes.

The entry also names several secondary outcomes but lists 0 analyses. This highlights the importance of accessible results, analysis populations, and methods for handling multiple outcomes and missing observations. Those details are not reported in the registry record. Statistical interpretation depends not only on endpoint definitions, but also on denominators, analysis decisions, and uncertainty.

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.

Several trial-specific limitations affect interpretation of the registry entry. First, it lists enrollment of 2 and describes a single-group design, with no separate control arm. The trial therefore cannot provide a direct comparison between the chemohormonal approach and another strategy. The record does not report a reason for choosing this design or a sample-size justification.

Second, the primary endpoint applies to participants who proceeded to surgery, but the number who underwent surgery and the number with an evaluable margin result are not reported. The observed surgical margin negative rate is also not reported. There is no posted confidence interval or other measure of precision.

Third, the registry lists five outcome measures but 0 analyses. Results for the secondary outcomes are not reported, and the statistical analysis plan, missing-data methods, and analysis populations beyond the primary endpoint population are not described. The handling of multiple outcomes is not reported in the registry record.

Fourth, the study status is TERMINATED, but the reason for termination is not reported. The record does not establish whether termination was related to recruitment, feasibility, safety, or another cause. It also does not explain whether all planned assessments were completed.

Finally, adverse-event reporting is limited to group counts. Serious adverse-event terms are not listed, other adverse events are not described by type, and deaths are not reported. These gaps prevent fuller assessment of the study's outcome and safety experience from the registry entry alone.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Neoadjuvant Chemohormonal Therapy Followed by Salvage Surgery for High Risk PSA — NCT01531205.
• Registry record last updated 2014-11-05; status last verified 2014-07.
• Results first posted 2014-08-05.
• 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

NCT01531205 is a phase 2, single-group trial titled “Neoadjuvant Chemohormonal Therapy Followed by Salvage Surgery for High Risk PSA.” It enrolled 2 participants, started in 2012-05, reached primary completion in 2013-09, and is listed as TERMINATED. The reason for termination is not reported in the registry record.

The planned intervention combined hormonal therapy and cabazitaxel before salvage surgery, with post-operative hormonal therapy and follow-up. The primary endpoint was the surgical margin negative rate one year after surgery among participants who proceeded to surgery. The registry lists five outcome measures and 0 analyses; primary and secondary outcome results are not reported.

For adverse events, 2 participants were at risk for serious events and 0 were affected; 2 were at risk for other events and 2 were affected. No serious-event terms are listed, and deaths are not reported.