Cryotherapy in Treating Patients With Primary Stage I Non-Small Cell Lung Cancer or Lung Metastasis: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Cryotherapy in Treating Patients With Primary Stage I Non-Small Cell Lung Cancer or Lung Metastasis (NCT00890617), a na phase 1 study. The primary outcome is The Number of Patients With a Response (Complete Response and Partial Response).

2. Clinical Question

3. Trial Design

This was a phase I pilot study, registered as NCT00890617, with a single-group model and enrollment of 9. The study concerned percutaneous cryotherapy for primary stage I non-small cell lung cancer or lung metastasis. The registry records one group, Prednisone & Cryotherapy. It lists cryotherapy as a procedure and prednisone as a drug, with prednisone scheduled around the procedure.

The record lists allocation as not applicable and masking as none. With no separate comparison group, this design describes outcomes among treated participants rather than estimating a comparative treatment effect. It cannot isolate the effect of cryotherapy from the effect of prednisone or from other influences on outcomes. The registry record does not report a control condition, random assignment, or masking procedures.

The primary outcome was the number of participants with a complete or partial response at 3 weeks post-Percutaneous Cryotherapy (PTC). The success definition refers to detailed histologic examination of resected ablated tissue: treatment success required > 75% of that tissue to show no cancer. A secondary outcome was the number of patients with a pathologic response. The registry lists 2 outcome measures and 0 analyses, but does not report the observed primary or secondary outcome counts.

The study is marked completed. Its recorded start was 2009-03, and its primary completion date was 2019-07-27. The registry record does not report the protocol’s detailed eligibility criteria, a sample-size justification, or a full statistical analysis plan. The stated objective was to estimate the PCA success rate; additional details about how that estimate was to be calculated 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

5. Baseline Characteristics

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

6. Primary Endpoint

The registry lists the primary outcome as The Number of Patients With a Response (Complete Response and Partial Response), measured over 3 weeks post-Percutaneous Cryotherapy (PTC).

The primary endpoint counts participants with a complete or partial response at 3 weeks post-Percutaneous Cryotherapy (PTC). Its success criterion is based on tissue pathology: > 75% of the resected ablated tissue must show no cancer on detailed histologic analysis. This links the response definition to examination of treated tissue rather than relying only on symptoms or imaging.

Counting participants with a response gives a binary outcome at the participant level: each participant either meets the response definition or does not. The study’s stated objective was to estimate the PCA success rate. In general, a success rate expresses the proportion of participants meeting the specified definition, and its precision depends on the amount of information available and the observed pattern of outcomes. The registry record does not report the primary response count or a success-rate estimate, so neither the observed rate nor its precision can be described.

The separate secondary outcome is the number of patients with a pathologic response. The registry record does not provide its definition, observed count, or analysis. It also does not clarify how the primary complete-or-partial response classification relates to the secondary pathologic-response measure. These omissions limit interpretation of how the endpoints were distinguished in practice.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The primary endpoint is a binary participant-level outcome: a participant is classified as having a complete or partial response or not having one. The stated success criterion requires > 75% of resected ablated tissue to show no cancer on detailed histologic analysis. The registry names the statistical objective as estimation of the PCA success rate. It does not report the analysis method used to make that estimate, an uncertainty interval, or the observed response count.

What does a response-rate estimate describe?

In general, a response-rate estimate is the proportion of assessed participants who meet the predefined response criteria. The estimate summarizes the observed participants, while an uncertainty interval describes how much imprecision remains about the underlying rate. A confidence interval is one common way to express that uncertainty; it gives a range of values compatible with the data under the method’s assumptions. It does not guarantee that the underlying rate lies in the interval, nor does it measure the probability that treatment caused the responses. No such interval is reported in the registry record.

Why does the single-group design matter?

A single-group study can describe what happened among participants who received the recorded intervention, but it does not directly estimate a contrast against an untreated or alternative-treatment group. Without a concurrent comparator, observed outcomes may reflect more than the intervention. Here the group is described as Prednisone & Cryotherapy, so outcomes cannot be attributed to cryotherapy alone from this design. General statistical reasoning also distinguishes estimation from causal comparison: a response rate is descriptive of the studied group, whereas a treatment effect requires a defensible comparison and assumptions appropriate to that design.

The registry lists allocation as not applicable and masking as none. It does not describe a randomized comparison or blinding. The record also does not describe how pathologists or other outcome assessors applied the tissue criterion, whether assessment was blinded, or how disagreements were resolved. Those operational details can matter for a pathology-based endpoint, but their absence from the record does not establish that any particular procedure was or was not used.

How should planning calculations be understood?

Any sample-size planning illustrations associated with this analysis are hypothetical planning exercises, not observed trial results or observed power. The stated illustration assumptions are a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation, with the target effect expressed as a fraction of the observed effect. These assumptions describe a planning framework rather than the design of this single-group study. The study itself has no two-arm randomized comparison, so an illustration framed around equal allocation between two arms should not be mistaken for the actual trial allocation or analysis.

In general, a sample-size calculation asks how much information a future study might need under specified assumptions about the effect, variability, error rates, and design. Its output depends on those assumptions. Planning illustrations based on an observed effect can be especially uncertain when the estimate comes from a small study, because the observed effect may be imprecise. They do not show that the original study had a particular probability of detecting an effect, and they do not replace a documented prospective sample-size rationale. The registry record does not report the trial’s own sample-size justification.

What is not documented about analysis?

The registry lists 0 analyses. That means the record does not include a reported analysis entry to interpret; it does not establish what analyses may have been conducted outside the registry record. No statistical model, estimator, confidence-interval method, or hypothesis test for the primary outcome is reported. The record likewise does not describe covariate adjustment, subgroup analyses, interim analyses, or a prespecified plan for handling multiple outcomes. These methods are not reported in the registry record and should not be inferred from the endpoint description alone.

General statistical principles help explain why these omissions matter. A prespecified analysis plan clarifies which outcome definition and analysis will be used, limiting ambiguity after results are known. For a binary endpoint, the handling of participants without an evaluable outcome can affect the denominator and interpretation of the estimated rate. With no reported account of outcome availability or missing-data handling, the analyzed population and any potential impact of missing information cannot be determined. The registry record does not report whether all enrolled participants contributed to the primary endpoint.

There are 2 outcome measures listed: the primary count of complete or partial responses and the secondary count of patients with a pathologic response. The record does not state how the secondary measure was defined or how the analyses accounted for examining more than one outcome. In general, multiplicity refers to the increased chance of a misleading finding when multiple hypotheses are tested; its relevance depends on the questions and analyses actually conducted. Since no analyses are reported, it is not possible to determine whether multiplicity adjustments were planned or 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("Prednisone & Cryotherapy")
n      <- c(9)
events <- c(8)
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  Prednisone & Cryotherapy  9  8  88.9  51.8  99.7  56.5  98.0  55.5  97.5

11. Multiplicity, Missing Data and Analysis Populations

The registry lists 2 outcome measures: the primary count of participants with a complete or partial response and the secondary count of patients with a pathologic response. It lists 0 analyses. The record does not report a multiplicity strategy, such as whether outcomes were treated as separate descriptive measures or whether formal hypothesis tests were planned. General statistical context: when several outcomes are tested, multiplicity can increase the chance of a chance-positive finding; whether adjustment is appropriate depends on the inferential goals and analysis plan. No such plan is reported.

The registry record does not report whether all 9 enrolled participants were assessed for the primary endpoint, how many had tissue available for histologic evaluation, or how missing, inadequate, or indeterminate assessments were handled. It also does not identify an analysis population, such as whether the endpoint was assessed in all enrolled participants or only those with evaluable tissue. These details matter because the denominator used for a response rate can affect its interpretation. No missing-data method or sensitivity analysis is reported.

The record states that the objective was to estimate the PCA success rate, but does not report the estimator, confidence interval, or other uncertainty measure. It also does not report a detailed statistical analysis plan, interim analyses, or a sample-size justification. Each of these items is not reported in the registry record; their absence from the record should not be read as evidence that a particular method was or was not used elsewhere.

12. Safety Results

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

Deaths

Other (non-serious) adverse events

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

Most frequent serious adverse event terms

Most frequent non-serious adverse event terms

Serious events with the highest arm-level rate: aspergillosis (11.1%), atrial fibrillation (11.1%).

For the Prednisone & Cryotherapy group, the registry records 9 participants at risk for serious adverse events and 2 affected by at least one serious adverse event. It records 9 participants at risk for other adverse events and 9 affected. The death count is 2. These are counts in the recorded group; they are not comparative estimates because no separate control group is listed.

The listed serious adverse-event terms are aspergillosis and atrial fibrillation, each reported as 11.1%. The registry record does not explain whether these percentages refer to participants, events, or another denominator. The terms should therefore be read as the registry’s reported figures rather than reinterpreted as a newly calculated patient-level risk.

The record does not state whether serious events or deaths were judged related to cryotherapy, prednisone, the underlying illness, or other causes. It also does not provide the safety follow-up period, event timing, severity details beyond the serious-event classification, or participant-level overlap among event categories. Counts describe what was recorded, but do not by themselves establish causation or permit comparison with another treatment.

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

The registry record identifies a phase I pilot study of percutaneous cryotherapy with prednisone in patients with primary stage I non-small cell lung cancer or lung metastasis. It defines a primary response endpoint based on complete or partial response and a pathology criterion requiring > 75% of resected ablated tissue to show no cancer. The assessment time is 3 weeks post-Percutaneous Cryotherapy (PTC). This information clarifies what the study intended to measure.

The record does not report the observed number of participants meeting the primary response definition or the PCA success-rate estimate. It therefore cannot establish the size or precision of the observed response rate. The secondary pathologic-response outcome is also listed without an observed count. The absence of those results in the registry record should not be interpreted as either a positive or a negative result.

The design also limits what a response count could establish. This was a single-group study, with no randomized comparator. Any observed responses would describe participants receiving the combined Prednisone & Cryotherapy intervention; they would not by themselves show what would have happened under another treatment or without treatment. The record cannot isolate the contribution of cryotherapy from prednisone or other influences.

Safety information is reported as group counts, including serious adverse events, other adverse events, and deaths. The registry does not provide attribution or enough detail to determine the cause of events, and it does not explain the derivation of the listed serious-event percentages. Those safety data should not be treated as a comparative estimate or as proof that an event was caused by treatment.

In general, a pilot study can contribute descriptive information and help frame questions for further study, but its interpretation depends on the outcomes actually reported and on the design. The registry record leaves the primary efficacy result, its uncertainty, missing-outcome handling, and detailed analysis methods unreported. Conclusions should remain limited to the recorded design, endpoint definitions, and safety counts.

14. Why This Trial Matters Statistically

This trial is statistically notable for the gap between a clearly described endpoint and the absence of a reported primary outcome value. The record defines response using detailed histologic assessment of resected ablated tissue and states that the objective was to estimate a success rate. Yet it does not report the response count, the estimate, or an uncertainty interval. Without those quantities, the main statistical objective cannot be evaluated from the registry record.

The single-group design is also central to interpretation. A rate estimated in one treated group is descriptive, not a randomized treatment contrast. The recorded group received both prednisone and cryotherapy, so the design does not distinguish their separate contributions. This is a general issue in single-arm studies: a clear endpoint does not create a comparator or remove the influence of factors that could affect outcomes.

Enrollment was 9, making precision particularly important to assess. General statistical reasoning indicates that limited information can leave a binary rate estimate uncertain; a point estimate alone, even if reported, would not communicate that uncertainty. In this record, neither the point estimate nor a precision measure is present.

The case also illustrates why endpoint definitions, analysis populations, missing-data handling, and analysis plans belong in a complete statistical interpretation. The histologic endpoint depends on tissue assessment, but the record does not report how many participants had evaluable specimens or how unassessable outcomes were handled. It lists a secondary pathologic-response measure but does not report its result or analytical relationship to the primary outcome. These are not minor details when interpreting an endpoint based on pathology.

Finally, the safety counts can be described, but the record does not establish event attribution or offer a comparison group. Statistical interpretation must distinguish recorded counts from causal conclusions. The study’s design and available reporting support a limited descriptive account, not an estimate of comparative benefit or risk.

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 registry record does not report the observed primary response count, the PCA success-rate estimate, or any uncertainty interval. It also does not report the secondary pathologic-response count. These missing outcome results prevent evaluation of the study’s stated estimation objective.

The single-group design and absence of a control group prevent a like-for-like treatment comparison. Prednisone was part of the recorded intervention group, so an outcome cannot be assigned to cryotherapy alone. Masking is listed as none, and the record does not describe outcome-assessor procedures or whether histologic assessment was blinded.

The endpoint depends on resected ablated tissue, but the registry record does not report how many participants had tissue suitable for assessment, the number with missing or indeterminate pathology, or the rules for determining an evaluable response. It does not identify the analysis population or describe missing-data handling. The secondary pathologic-response measure is listed without a detailed definition.

The record does not report the trial’s sample-size justification, a detailed statistical analysis plan, a confidence-interval method, or whether interim analyses were conducted. It also does not explain how multiple outcomes were addressed. The listed planning assumptions for sample-size illustrations do not constitute the original trial’s design rationale or an analysis of observed treatment effect.

For safety, the registry provides group counts and two serious-event terms with percentages, but does not explain the percentage denominator, event attribution, follow-up period, timing, or overlap among categories. As a result, safety counts are descriptive and cannot support comparative or causal interpretation. These limitations reflect details not reported in the registry record; they do not establish what procedures may have been documented elsewhere.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Cryotherapy in Treating Patients With Primary Stage I Non-Small Cell Lung Cancer or Lung Metastasis — NCT00890617.
• Registry record last updated 2022-11-01; status last verified 2022-10.
• Results first posted 2020-07-29.
• 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

NCT00890617 is a completed phase I, single-group pilot study of percutaneous cryotherapy with prednisone for primary stage I non-small cell lung cancer or lung metastasis. Enrollment was 9. Allocation is listed as not applicable and masking as none.

The primary outcome was the number of participants with complete or partial response at 3 weeks post-Percutaneous Cryotherapy (PTC). Treatment success was defined as > 75% of resected ablated tissue showing no cancer on detailed histologic analysis. The record states that the primary statistical objective was to estimate the PCA success rate. A secondary outcome was the number of patients with a pathologic response.

The registry records 2 participants affected by serious adverse events, 9 affected by other adverse events, and 2 deaths. Aspergillosis and atrial fibrillation are listed as serious adverse-event terms, each at 11.1%. The primary response result, secondary outcome result, analysis details, missing-data handling, and event attribution are not reported in the registry record.