Pemetrexed and Cisplatin Treatment Before Surgery in Non Small Cell Lung Cancer: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Pemetrexed and Cisplatin Treatment Before Surgery in Non Small Cell Lung Cancer (NCT00259285), a non-randomized phase 2 study. The primary outcome is Treatment Response.

2. Clinical Question

This is a question about observed response in a group receiving the regimen, not a randomized estimate of how the regimen compares with an alternative. Without a reported response count, the registry record cannot establish the observed frequency or types of response in this study. Even if such a count were available, the single-group design would limit interpretation: changes observed during treatment could not be separated from differences in disease course or other factors using a randomized comparator. The record also lists pathologic remissions after surgery and relapse-free survival as secondary outcomes, but their results are not reported in the registry record.

3. Trial Design

The study is registered as Phase 2 and has a single-group, non-randomized, unmasked design. Its listed intervention was pemetrexed plus cisplatin as treatment before surgery for non-small-cell lung cancer. The brief summary says the intended purpose was to determine response in people with locally advanced or metastatic disease. The registry lists 10 participants enrolled. Enrollment does not by itself show how many completed treatment, underwent surgery, or contributed data to any particular outcome; those details are not reported in the registry record.

The registry gives a start date of 2005-11 and a primary completion date of 2007-12. Its status is terminated. The reason for termination, the number treated, and the duration of follow-up are not reported in the registry record. Termination describes the recorded study status, but it does not explain why the study ended or what conclusions investigators drew.

There is no randomized allocation and no control arm described. The record therefore characterizes a treatment group rather than a comparative trial. Masking is listed as none; further details about outcome assessment procedures are not reported. The primary endpoint is Treatment Response, assessed using RECIST, with the stated assessment timeframe of every 21 day cycle (3 cycles) and 3-4 weeks after the last cycle. The secondary outcomes listed are Pathologic Remissions After Surgery and Relapse-free Survival. Although the record lists 3 outcome measures, it reports 0 analyses.

A sample-size planning illustration, where displayed, should not be interpreted as the original trial design or as evidence about the number needed for a future study. The stated illustration assumptions describe a two-arm calculation, whereas this trial is single-group. The registry record does not report the trial's own sample-size justification, a planned target enrollment beyond the recorded enrollment, or a statistical analysis plan. The illustration's assumptions and any calculated planning values do not turn this study into a comparative trial.

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 Treatment Response, measured over every 21 day cycle (3 cycles) and 3-4 weeks after last cycle.

The primary endpoint is titled Treatment Response and is measured in participants. The registry description defines it as the best response recorded from the start of treatment until disease progression or recurrence, using Response Evaluation Criteria in Solid Tumors (RECIST). In the description, response categories distinguish improvement, stability, and progression. Assessment is scheduled every 21 day cycle (3 cycles) and 3-4 weeks after the last cycle.

In general, a response endpoint can summarize whether disease has changed according to prespecified assessment criteria during treatment. Recording the best response over a stated interval is intended to capture the most favorable recorded category in that interval, rather than only a single assessment. It is important to distinguish that definition from a result: the registry record gives the measurement approach and timeframe but does not report how many participants were in each response category, or the best response distribution.

RECIST provides a standardized framework for classifying tumor response, which can make assessments more consistent than an informal description. However, the outcome still depends on available assessments and the rules used to classify them. The record does not report details such as assessability, handling of missing scans, confirmation requirements, or the precise analysis population. Those aspects should not be inferred from the endpoint title alone.

The listed secondary outcomes are pathologic remissions after surgery and relapse-free survival. These address different aspects of the clinical course from the primary response measure: one concerns findings after surgery and the other concerns time without relapse. Their definitions, assessment details, and results are not reported in the registry record. No conclusion about those outcomes can be drawn from their names alone.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

Statistical interpretation depends on separating the design, endpoint definition, observed data, and analysis. In this study, the design is recorded as single-group and non-randomized. The primary endpoint is Treatment Response, described using RECIST. The registry identifies 10 enrolled participants, but it does not report a primary response result or an analysis. Thus, the endpoint definition is available while the numerical outcome evidence is not.

What does a single-group design estimate?

General explanation: a single-group study can describe outcomes observed among people who receive an intervention. It does not create a randomized counterfactual group showing what would have happened to comparable participants under another intervention. Randomization helps balance measured and unmeasured factors on average between groups; without it, differences between groups, if any exist, may reflect factors other than treatment. Here there is no randomized comparator described, so a treatment-versus-control effect cannot be estimated from the design recorded.

A within-group response count, if reported, would answer a descriptive question about the participants observed in the study. It would not by itself establish that the regimen caused the responses. In this case the registry record does not report the response count, so even a descriptive response frequency is unavailable. The enrollment count should not be substituted for an outcome denominator: the number assessed for response and the number included in any analysis are not reported.

How should the response endpoint be understood?

General explanation: a categorical response endpoint groups participants according to defined states, such as response, stable disease, or progression. A best-response measure uses the most favorable recorded category over the specified assessment period. Standard criteria such as RECIST aim to make tumor-response classifications more consistent. They do not guarantee that every participant has an evaluable assessment, nor do they specify how missing or unconfirmed assessments were handled. Those details are not reported in the registry record.

The recorded assessment timeframe is every 21 day cycle (3 cycles) and 3-4 weeks after the last cycle. This specifies planned assessment timing, not the completeness of those assessments or the follow-up actually achieved. It also does not provide the response result. The registry record does not report the number in each response category, the response analysis population, or uncertainty around an estimate.

What does uncertainty add?

General explanation: an estimate describes an observed quantity, while a confidence interval conveys how much statistical uncertainty accompanies that estimate under a specified method. In a small study, outcome estimates can be imprecise, especially when events are uncommon. A broad interval signals that the data may be compatible with a range of underlying values. An interval does not address systematic biases, establish causality, or make a non-comparative design equivalent to a randomized study.

No response estimate, confidence interval, or inferential result is reported in the registry record. Therefore, precision cannot be evaluated for the primary outcome. No significance test or adjusted analysis is reported either. The record does not describe the intended statistical model, testing procedure, or handling of multiple outcomes. These items should be treated as unreported, rather than reconstructed from the endpoint description.

What do sample-size illustrations mean?

General explanation: a sample-size calculation is a planning exercise. It depends on assumptions about the effect to detect, the variability or event rate, the significance level, allocation, and the statistical method. It does not describe what was observed, and it is not an observed-power calculation. The stated sample-size illustration uses a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation; the effect to detect is described as a stated fraction of the observed effect. For time-to-event illustrations, the stated quantity is total events; other illustrations refer to participants per arm.

Those are planning assumptions, not the recorded design of this trial. The trial is single-group, while the illustration describes two-arm allocation. The registry record does not report the trial's own sample-size justification or establish that the illustration's assumptions were used when the study was designed. Any sample-size values should therefore be read as hypothetical planning quantities, not as evidence that the study had adequate or inadequate power, and not as a result from the enrolled participants.

How should the adverse-event entries be read?

General explanation: adverse-event summaries need a clear denominator, a defined observation period, and consistent rules for what qualifies as an event. The registry lists 1 serious and 8 other affected participants for the Pemetrexed + Cisplatin group, but at-risk counts are not reported. It also lists urinary tract infection at 10.0% among serious terms. The record does not supply enough context to derive a broader incidence estimate or compare risk with another group. No such recalculation is warranted from the listed entries.

Overall, the methods information supports a limited account of the endpoint definition and study structure. It does not support a numerical treatment-response conclusion, a causal estimate, or a full assessment of statistical precision.

10. Multiplicity, Missing Data and Analysis Populations

The registry lists 3 outcome measures, including Treatment Response, Pathologic Remissions After Surgery, and Relapse-free Survival. It reports 0 analyses. The record does not specify which outcomes were formally tested, whether any were designated for confirmatory inference, or how multiplicity was handled. The analysis plan and any adjustment for multiple comparisons are not reported in the registry record.

General explanation: when several outcomes or statistical tests are examined, the chance of at least one apparently notable result can increase unless the analysis accounts for multiplicity. Different approaches can prioritize one primary outcome, adjust significance thresholds, or treat secondary findings as exploratory. Which approach is appropriate depends on the study plan and purpose. No approach should be attributed to this study without documentation.

Missing-data procedures are also not reported in the registry record. It does not say how incomplete response assessments, loss to follow-up, withdrawal, or unavailable post-surgery findings were handled. Nor does it give the number of participants assessed for each outcome or define the analysis population. Enrollment of 10 participants is not necessarily the denominator for every outcome.

These omissions matter because outcome availability and analysis choices can affect the estimate and its interpretation. For example, a best-response summary depends on which scheduled assessments were available and how non-evaluable cases were treated. Relapse-free survival requires follow-up and event definitions, while the record does not give a time-to-event analysis or its censoring rules. The registry record therefore does not support conclusions about missingness, outcome completeness, multiplicity control, or the population included in analysis.

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

The record establishes that a Phase 2, non-randomized, single-group study of pemetrexed and cisplatin before surgery was registered for non-small-cell lung cancer. It records 10 participants enrolled, a Treatment Response primary endpoint assessed using RECIST, and a terminated status. It also lists pathologic remissions after surgery and relapse-free survival as secondary outcomes. These are details about the design and registered outcomes; they are not evidence of a particular response or survival result.

The record does not report the primary response result, the secondary outcome results, or an analysis. It therefore cannot show from the posted results how many participants responded, remained stable, progressed, had pathologic remission, or experienced relapse. The absence of these results in the registry record is not a finding that those events did or did not occur.

Even if a response count were available, the single-group design would describe outcomes in the treated group rather than establish a causal treatment effect. No randomized control group is recorded, so the study does not provide a randomized comparison with another treatment or control condition. The record also does not report an analysis that estimates comparative benefit or risk.

The adverse-event entries are limited to the recorded group-level counts and a serious urinary tract infection term listed at 10.0%. With at-risk counts not reported and no comparator described, those entries cannot provide a complete comparative safety assessment. The reason the study was terminated is not reported in the registry record.

In general, a trial result should be interpreted with its estimate, uncertainty, analysis population, and design in view. Here, the endpoint definition and design are recorded, but the outcome estimates and statistical analyses are absent. Accordingly, no conclusion about treatment effectiveness, lack of effectiveness, or comparative safety should be drawn from this registry record alone.

12. Why This Trial Matters Statistically

This study is statistically informative as an example of the distinction between a clearly named endpoint and a reported result. Treatment Response is defined with a framework and assessment schedule, but the registry does not report the response distribution or an analysis. A reader cannot infer an effect estimate merely from the fact that the outcome was planned or measured.

The single-group design also makes the estimand important. A descriptive response proportion would concern outcomes among the treated participants; a comparative treatment effect would require a suitable comparator and assumptions supporting that comparison. The registry records no randomized control arm. This difference helps prevent a common interpretive error: treating a within-group observation as proof of what the intervention caused.

Enrollment of 10 participants further underscores why outcome denominators and uncertainty matter. The record does not say how many participants were evaluable for each outcome, so even the relevant analysis population is unknown. General statistical principle: estimates from small groups can be sensitive to individual observations and may have substantial uncertainty. Without an estimate and interval, precision cannot be assessed. This principle does not supply a missing result.

The record also lists secondary outcomes and adverse-event entries, but no analysis. This illustrates the need for transparent reporting of outcome definitions, missing-data rules, follow-up, and multiplicity handling. The sample-size illustration assumptions, if consulted, are planning assumptions rather than evidence about observed outcomes or the trial's original design. They describe a two-arm calculation, while the recorded study is single-group.

The statistical importance of the study record lies in understanding what it does and does not document: the population intent, regimen, endpoint framework, and design are described, but treatment-response results and inferential analyses are not. That distinction is essential for responsible interpretation.

13. 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 main trial-specific limitation is the absence of reported primary and secondary outcome results. Although Treatment Response is defined and the registry lists 3 outcome measures, the record reports 0 analyses. It does not provide response categories, pathologic remission results, relapse-free survival estimates, or uncertainty measures. Consequently, neither the magnitude nor precision of the outcomes can be assessed.

The study is recorded as non-randomized and single-group, without masking. No like-for-like control comparison is available in the design description. This restricts causal interpretation even if an outcome estimate were reported. The record does not provide enough detail to assess potential selection effects, baseline disease characteristics, or the comparability of participants with any external population.

The enrollment count is 10, but the number treated, assessed, and included in each outcome analysis is not reported in the registry record. The record does not explain whether participants underwent surgery, how response assessments were completed, or how incomplete assessments and follow-up were handled. The primary completion date is recorded as 2007-12, and the status is terminated, but the reason for termination and follow-up duration are not reported.

Safety interpretation is constrained by absent at-risk counts and limited event context. The record lists 1 serious and 8 other affected participants in the treatment group and urinary tract infection at 10.0% among serious terms, but it does not provide a comparator or enough information for a broader safety comparison. The statistical analysis plan, sample-size justification, multiplicity approach, and analysis populations are also not reported in the registry record.

14. Related Tutorials

15. Related Statistical Calculators

16. Sources

• ClinicalTrials.gov: Pemetrexed and Cisplatin Treatment Before Surgery in Non Small Cell Lung Cancer — NCT00259285.
• Registry record last updated 2009-06-02; status last verified 2009-04.
• Results first posted 2009-06-02.
• 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.

17. Record Summary

NCT00259285 is a Phase 2 study titled Pemetrexed and Cisplatin Treatment Before Surgery in Non Small Cell Lung Cancer. It is recorded as non-randomized, unmasked, and single-group, with pemetrexed plus cisplatin as neoadjuvant treatment. The registry lists 10 participants enrolled, a start date of 2005-11, a primary completion date of 2007-12, and a terminated status.

The primary outcome is Treatment Response, defined using RECIST and assessed every 21 day cycle (3 cycles) and 3-4 weeks after the last cycle. Secondary outcomes are Pathologic Remissions After Surgery and Relapse-free Survival. The registry lists 3 outcome measures and reports 0 analyses. Primary and secondary outcome results are not reported in the registry record.

The record lists 1 serious and 8 other affected participants for the treatment group, with at-risk counts not reported, and urinary tract infection at 10.0% among serious terms. The reason for termination, analysis populations, missing-data procedures, and statistical analysis plan are not reported.