Neoadjuvant Platinum-based Chemoradiation Therapy for Locally Advanced Triple Negative Breast Cancer: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Neoadjuvant Platinum-based Chemoradiation Therapy for Locally Advanced Triple Negative Breast Cancer (NCT01167192), a na phase 2 study. The primary outcome is Response Rate as Measured by Number of Participants Who Achieved Complete Response (CR) or Partial Response (PR).

2. Clinical Question

3. Trial Design

This was a phase 2, single-group study sponsored by Washington University School of Medicine. The registry lists enrollment of 10, a start date of 2011-02, primary completion in 2012-08, and a status of terminated. The reason for termination is not reported in the registry record.

The treatment was neoadjuvant: chemotherapy and radiation were intended before surgery. Participants received either cisplatin or carboplatin, with radiation therapy. The arm description specifies cisplatin or carboplatin on a repeated schedule and radiation beginning during treatment; it also describes mastectomy and adjuvant chemotherapy as recommended. Mastectomy was recommended but not mandatory. The registry record does not establish whether each participant received every planned component or completed the regimen.

Because the study has a single group and no allocation to a control group, its structure is descriptive rather than a randomized comparison. Cisplatin and carboplatin appear as treatment alternatives in the same group; the record does not report separate results for participants receiving each drug. Masking is listed as none. These features matter when interpreting any observed response: without a concurrent comparator, a response count alone cannot isolate the effect of the regimen from other influences or establish how outcomes would have differed under another treatment.

The primary endpoint was a participant count for complete or partial response before surgery, with the assessment timeframe described as approximately 12-16 weeks from registration. The record also names secondary outcomes covering disease progression, surgical complications, bone marrow disseminated cancer cells, overall survival, grade 3 or higher adverse events, and development and behavior of animal models. Although these outcome areas are listed, their results are not reported in the registry record. The record contains no analysis entries.

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: 1 patient was removed from study due to treatment related toxicity prior to efficacy evaluation and 1 patient expired prior to efficacy evaluation. These two patients are not included in this outcome measure.

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 Response Rate as Measured by Number of Participants Who Achieved Complete Response (CR) or Partial Response (PR), measured over Prior to surgery (approximately 12-16 weeks from registration).

The primary endpoint counts participants who achieved either a complete response (CR) or a partial response (PR) before surgery. The stated assessment time was approximately 12-16 weeks from registration. CR required disappearance of all target lesions and all non-target lesions, together with normalization of the tumor marker level. PR required at least a 30% decrease in the sum of the longest diameters of target lesions, using the baseline sum as the reference.

In general, combining complete and partial responses gives a count of participants meeting either of the registry's response definitions. This can provide a clinically interpretable description of tumor response during preoperative treatment. The count is not itself a measure of how long response lasts, whether disease progresses later, or survival. Those are distinct outcome questions, and the registry lists some of them as secondary outcomes.

The endpoint is recorded as a count of participants, not as a response rate with a reported denominator. The registry record does not report how many participants achieved CR or PR, nor a corresponding estimate of uncertainty. It also states that one participant was removed because of treatment-related toxicity before efficacy evaluation and one participant expired before efficacy evaluation; those two participants were excluded from this outcome measure. The record does not report additional details about assessment or endpoint handling.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The primary outcome is a binary participant-level event: a participant either met the CR-or-PR definition or did not. The registry records the outcome unit as participants and the parameter as a count. This distinction is useful. A count tells how many participants met the criterion, whereas a response proportion would additionally express that count relative to a stated denominator. The registry does not report the response count or a response proportion.

What does the endpoint combine?

The endpoint combines CR and PR into one response category. CR requires disappearance of target and non-target lesions and normalization of the tumor marker level. PR is defined by at least a 30% reduction in the sum of the longest diameters of target lesions, compared with baseline. In general, such a combined endpoint can describe whether participants met either predefined response threshold. It does not preserve the distinction between complete and partial response unless separate counts are also reported. The registry record does not report those separate counts.

The assessment is specified as occurring before surgery, at approximately 12-16 weeks from registration. In general, specifying a timeframe helps define when an outcome is to be assessed and prevents an endpoint from being interpreted as though it covered all later follow-up. The record gives this intended timeframe but does not report participant-level assessment timing, the number assessed, or the response result.

What can a confidence interval tell a reader?

In general, a confidence interval describes the precision of an estimate under a statistical model. For a binary outcome, an interval around a response proportion can help show how compatible the data are with a range of underlying response probabilities. It is not a guarantee that the true value lies within a particular interval, and it does not correct for design limitations such as having no control group. No confidence interval for the primary response outcome is reported in the registry record, so its precision cannot be assessed from the posted results.

Similarly, a p-value is a statistic that measures how surprising data would be under a specified null hypothesis and model. Its interpretation depends on the analysis question and assumptions. A p-value cannot establish causation in a single-group study or compensate for an absent comparator. The registry record does not report a primary-outcome p-value or analysis, and no statistical analysis entries are recorded.

Why does the single-group design matter?

In general, an uncontrolled single-group study can describe outcomes among treated participants, but it does not directly estimate a treatment contrast against a concurrent control group. Participant characteristics, the natural course of disease, treatment components, and other influences can all affect observed outcomes. A comparison with an external result would require additional information and assumptions that are not documented in this record. The registry lists cisplatin or carboplatin as alternatives, but does not report separate results or a drug-to-drug comparison.

Masking is listed as none. In general, lack of masking can matter when outcomes involve judgment or assessment, because knowledge of treatment may influence measurement or classification. The registry supplies response definitions, but does not report how assessments were conducted or whether any review procedures were used. No further inference about the assessment process is warranted.

How should planning calculations be distinguished from trial results?

In general, sample-size calculations use assumptions about the outcome, target effect, significance level, power, allocation, and analysis method. A planning illustration is not evidence that a study had that power, nor does it show that the planned effect was achieved. The registry's stated illustration assumptions describe 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. The record characterizes these as planning assumptions, not the trial's own design. Since this study is single-group, a two-arm allocation assumption in a planning illustration should not be mistaken for the actual study design.

The illustration also cannot supply a missing outcome estimate. The primary response count and its uncertainty are not reported in the registry record. The sample-size justification used when designing the study, if any, is not reported in the registry record. The statistical analysis plan and any interim analyses are also not reported in the registry record. These distinctions prevent planning conventions from being misread as evidence about what the study found.

What role does over-dispersion play in general?

For count outcomes, some statistical models assume that variation follows a specified relationship to the average count. Over-dispersion means the observed variation is greater than that model expects. In general, failing to account for over-dispersion can make uncertainty estimates too narrow. This concept does not establish that over-dispersion was present in this trial: the primary outcome is a participant count, and the registry does not report a model, dispersion estimate, or analysis of the response endpoint.

Overall, the record supplies an endpoint definition and a study structure, but not the outcome data or inferential analysis needed to judge the observed response count or its precision. General statistical concepts can clarify what those missing elements would mean, but they cannot substitute for results that are not reported.

10. Multiplicity, Missing Data and Analysis Populations

The registry lists a primary endpoint and multiple secondary outcomes. The secondary outcomes include time to disease progression, surgical complications, disseminated cancer cells in bone marrow, overall survival, grade 3 or higher adverse events, and outcomes concerning development and behavior of animal models. When a study evaluates multiple outcomes, the chance of at least one apparently notable result can increase if many statistical tests are performed. In general, multiplicity procedures can address this issue, but the appropriate approach depends on the study questions and analysis plan.

Whether multiplicity was addressed, and by what method, is not reported in the registry record. The record contains no analysis entries, so it does not describe which outcomes were analyzed, which tests were used, or whether any adjustment was planned. The presence of several registered outcomes alone does not establish that multiple hypothesis tests were conducted.

The primary endpoint population description identifies two participants excluded before efficacy evaluation: one removed because of treatment-related toxicity and one who expired. Those exclusions are explicitly stated for this outcome. The registry does not report additional missing-data rules, imputation, sensitivity analyses, or whether other participants lacked endpoint assessments. It also does not report a broader analysis-population definition, such as a rule for including or excluding participants based on treatment received or protocol completion. These details should not be inferred from the listed enrollment or safety counts.

Because the primary response count is not reported, the effect of the stated exclusions on an estimated response proportion cannot be evaluated from the registry record. Any general discussion of missing-data methods is methodological context, not a description of methods used in this study.

11. 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 (25.0%), chills (25.0%), decreased lymphocytes (25.0%), fever (25.0%), hypoalbuminemia (25.0%).

The registry reports a safety group with 8 participants at risk for serious adverse events and 3 affected. For other adverse events, it reports 8 participants at risk and 8 affected. These are group-level counts as recorded; they are not efficacy results, and they do not by themselves establish that treatment caused an event. The registry does not report the number of deaths in this safety entry.

The serious adverse event terms listed are anemia, chills, decreased lymphocytes, fever, hypoalbuminemia, and increased creatinine. Each term is accompanied by 25.0%. The denominator and the event-count basis for those percentages are not reported in the registry record. The listed terms should therefore be read as registry safety entries, not as a complete account of all possible events or as proof that each term affected a distinct participant.

Seriousness and severity are not interchangeable concepts. The registry separately lists grade 3 or higher adverse events as a secondary outcome, but its result is not reported in the registry record. The serious-event counts should not be treated as a count of grade 3 or higher events unless the record explicitly makes that link. The safety information describes reported events in this study group and does not provide a controlled comparison of risks.

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

The study record identifies a specific question: whether participants receiving neoadjuvant platinum-based chemotherapy with radiation achieved a complete or partial response before surgery. It defines both response categories and gives an approximate assessment timeframe. It also records enrollment, the single-group design, and safety counts. These details help clarify what the trial intended to examine and how its primary outcome was defined.

The record does not report the number of participants who achieved CR or PR. It therefore does not establish the observed response level, the precision of an estimate, or whether outcomes differed across the response categories. No primary statistical analysis is recorded. The available information cannot support a conclusion about the size or reliability of the response result.

Even if a response count were reported, a single-group result would describe outcomes in this study rather than directly compare the regimen with another treatment. With no concurrent control group, the record cannot establish what would have happened to comparable participants under an alternative. It also cannot distinguish the effects of chemotherapy from radiation or other treatment components. Cisplatin and carboplatin were alternatives within the group, and separate comparative results are not reported.

The listed secondary outcomes do not resolve these gaps because their results are not reported in the registry record. Nor does the terminated status explain the study findings: the reason for termination is not reported. The safety entries describe reported adverse events, but do not establish comparative risk or causation. In general, interpreting a clinical trial requires both outcome estimates and their uncertainty, alongside attention to design and analysis. Here, the definitions and design are documented, while the primary response result and inferential analysis are not.

13. Why This Trial Matters Statistically

This trial is statistically instructive because its registered question and endpoint are more complete than its reported efficacy results. The endpoint has a stated unit, clinical response definitions, and an intended assessment time. Those elements make clear what would count as a response. However, a precise definition does not replace the outcome count, denominator, or uncertainty estimate needed to understand what was observed.

The single-group structure also illustrates the difference between describing outcomes and estimating a comparative treatment effect. A count of participants with CR or PR could summarize experience in the treated group, but would not by itself quantify how that experience compares with an alternative. The presence of two platinum options within one group does not create a randomized comparison between them.

The record also highlights why analysis populations and missing outcomes matter. It specifically excludes two participants from the efficacy endpoint before evaluation, for stated reasons. Without a reported response count, further details about assessments, and a stated missing-data strategy, readers cannot determine how the endpoint population relates to all enrolled participants or how uncertainty should be interpreted.

Finally, registered secondary outcomes and safety entries should not be mistaken for complete results. A registry can specify what was intended to be measured while leaving outcome analyses unreported. Statistical interpretation therefore depends not only on study design and endpoint definitions, but also on transparent reporting of estimates, precision, analysis choices, and missing-data handling. Those result and analysis details are not reported in the registry record.

14. 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 most direct limitation is that the primary response count is not reported in the registry record. Without that result, neither the observed response level nor its precision can be assessed. The record also has no analysis entries, leaving the statistical methods used for the endpoint undocumented.

The study enrolled 10 participants and used a single-group design, with no concurrent control group. This limits the ability to make comparative claims. Cisplatin and carboplatin were alternative components of the group, but separate outcomes by drug are not reported. The record also lists no masking.

The endpoint population description excludes one participant removed because of treatment-related toxicity before efficacy evaluation and one participant who expired before efficacy evaluation. The record does not report further details about missing efficacy assessments, missing-data methods, or other analysis-population rules. The reason for study termination is not reported in the registry record.

The registry lists several secondary outcome areas, but does not report their results or how multiplicity was handled. For safety, the record provides affected counts and listed serious-event terms, but does not report a death count; the basis for the term percentages is also not reported. These omissions restrict interpretation of both efficacy and safety. They do not establish that an outcome was absent or that an analysis was not performed outside the registry; they mean that the relevant information is not reported in the registry record.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Neoadjuvant Platinum-based Chemoradiation Therapy for Locally Advanced Triple Negative Breast Cancer — NCT01167192.
• Registry record last updated 2016-12-30; status last verified 2016-11.
• Results first posted 2016-10-28.
• 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.

18. Record Summary

NCT01167192 is a phase 2, single-group study sponsored by Washington University School of Medicine, with enrollment of 10 and status listed as terminated. It examined cisplatin or carboplatin with radiation before surgery for locally advanced triple-negative breast cancer. Mastectomy was recommended but not mandatory.

The primary outcome was the number of participants with complete or partial response before surgery, at approximately 12-16 weeks from registration. The response definitions are recorded, but the response count and statistical analysis are not reported in the registry record. The efficacy population description excludes one participant removed because of treatment-related toxicity before evaluation and one who expired before evaluation.

The registry lists secondary outcome areas and safety counts, including 3 affected participants among 8 at risk for serious adverse events. The reason for termination, sample-size justification, statistical plan, interim analyses, and results for the listed secondary outcomes are not reported in the registry record.