This page provides an independent statistical analysis and educational interpretation of publicly reported results. ClinicalTrials.gov provides the official trial registry record. Numerical trial results on this page are restricted to the results posted in the ClinicalTrials.gov record; calculations added by Clinical Biostats are labelled as such.
1. Trial at a Glance
This page covers the registry results for Efficacy Study of Dasatinib in Locally Advanced Triple-Negative Breast Cancer Patients (NCT00817531), a na phase 2 study. The primary outcome is Clinical Efficacy.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00817531 |
| Phase | Phase 2 |
| Condition | Breast Cancer |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 22 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Baylor Breast Care Center |
| Results posted | Yes |
2. Clinical Question
The study asked whether dasatinib could produce a clinical response in previously untreated, locally advanced triple-negative breast cancer. Its neoadjuvant setting was intended to assess cancer changes after treatment and before surgery. The registry record describes this as a biologic efficacy study, but it does not report the response results or an analysis of the primary outcome.
Population
Women with locally advanced triple-negative breast cancer who had not received treatment for their breast cancer. The primary-outcome description says all patients who started treatment would be included in the analysis; the number who started is not reported in the registry record.
Intervention
Open-label dasatinib, listed in the arm description as Dasatinib / Sprycel 100 mg.
Comparator
No concurrent comparator group is listed. The allocation field is recorded as NA, and the study is classified as single group.
Primary question
What clinical response was observed by RECIST assessment of the target lesion, based on changes in its longest diameter, at pre-surgery or after 3 to 4 weeks of treatment?
This design can describe outcomes among participants treated in the study, but it does not provide a randomized comparison of dasatinib with another treatment or with no treatment. Without posted outcome counts, the registry record does not establish how many participants had complete response, partial response, stable disease, or progressive disease. Nor does it report how the investigators interpreted the biological changes they hoped to study.
3. Trial Design
This phase 2 study is registered as a single-group, open-label trial of dasatinib for locally advanced triple-negative breast cancer. The record lists an enrollment of 22 and identifies Baylor Breast Care Center as the sponsor. It lists the study start as 2008-12, primary completion as 2011-02, and status as terminated. The reason for termination is not reported in the registry record.
The intervention is described as Dasatinib / Sprycel 100 mg, taken by all subjects in the open-label arm. Open-label means that the record does not describe masking of treatment assignment. The masking field is NONE. Allocation is NA, consistent with the single-group classification; no randomized assignment or concurrent control arm is described. Thus, the design does not support a like-for-like comparison between treatment groups.
The study is described as neoadjuvant: it was open to women who had not received treatment for their breast cancer, and the stated aim included looking at cancer-cell changes after study medication. The primary outcome timeframe is assessment at pre-surgery or 3 to 4 weeks of treatment. The record does not report the specific timing of assessment for each participant.
The registry identifies one primary outcome measure, Clinical Efficacy, measured in participants. The primary-outcome description says all patients who started treatment would be included in the analysis. The actual number who started treatment, the number assessed, and the number included in an analysis are not reported in the registry record. Although the record gives an enrollment figure, it does not provide participant flow or primary-outcome counts. It lists zero analyses, so no analysis results accompany the outcome description.
These design features matter when interpreting the evidence. A single-group study can document clinical responses in the treated group, but in the absence of a concurrent comparator it cannot separate a treatment-associated change from other possible explanations. Open-label assessment may also differ from a masked design. The registry record does not report procedures intended to address that concern.
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.
Before assignment: each patient have to be eligible and pass all screening tests after signing the consent to be enrolled in the study.
Overall Study
| Stage | Dasatinib |
|---|---|
| STARTED | 22 |
| COMPLETED | 20 |
| NOT COMPLETED | 2 |
Reasons for not completing this period:
| Reason | Dasatinib |
|---|---|
| Adverse Event | 1 |
| Lack of Efficacy | 1 |
Analysis population for the primary outcome, as defined in the registry: All patients started the treatment will be included in the analysis
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.
| Characteristic | Unit | Dasatinib |
|---|---|---|
| Participants analysed | 22 | |
| Age, Categorical: <=18 years | Participants | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 20 |
| Age, Categorical: >=65 years | Participants | 2 |
| Age Continuous | years | 48.5 (SD 12.7) |
| Sex: Female, Male: Female | Participants | 22 |
| Sex: Female, Male: Male | Participants | 0 |
| Region of Enrollment: United States | participants | 22 |
6. Primary Endpoint
The registry lists the primary outcome as Clinical Efficacy, measured over Assessment at pre-surgery or 3 to 4 weeks of treatment..
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | not applicable |
| Unit | participants |
| Endpoint classification | Binary Endpoint |
The primary endpoint is titled Clinical Efficacy and is measured as a number of participants. The description says clinical response was assessed using RECIST and based on changes in the longest diameter of the target lesion. Complete response means disappearance of the target lesion. Partial response means a decrease of 30% or greater in its diameter compared with baseline. Progressive disease means an increase of 20% or greater, using the smallest diameter recorded since baseline as the reference, or the appearance of a new lesion. Stable disease means neither enough shrinkage for partial response nor enough increase for progressive disease.
These categories provide a structured way to describe how measurable disease changes over an assessment period. Measuring the target lesion against baseline, and defining response categories in advance, helps make the classification more consistent than an unstructured clinical impression. The record places assessment at pre-surgery or 3 to 4 weeks of treatment, so the endpoint concerns an early response assessment rather than a reported long-term outcome.
The registry record gives the endpoint definition but not the number of participants in each response category, the response rate, or an uncertainty interval. It therefore does not show the magnitude or precision of the observed clinical response. The number of target lesions assessed per participant and details of how missing or unevaluable measurements were handled are not reported in the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record describes the study question and the intended response assessment, but it does not report the primary-outcome results. It gives no counts for complete response, partial response, stable disease, or progressive disease, and no estimate of clinical response is listed. Consequently, the posted record does not allow a reader to judge the frequency of response or the precision of any estimate. It also does not report a statistical analysis of the primary endpoint.
The distinction between a planned outcome and a reported result is essential. The RECIST definitions specify how a response category would be assigned from changes in target-lesion diameter. They do not, on their own, show what happened to participants. An outcome title, assessment timeframe, and analysis-population statement are not substitutes for observed counts. The registry lists an enrollment of 22, but the number who started treatment, had an assessment, or contributed to an outcome analysis is not reported in the registry record.
The single-group design also limits what any response count could establish. If counts were available, they would describe outcomes in the treated group over the stated assessment period. Without a concurrent control group, a difference attributable to dasatinib could not be estimated from this design alone. The record does not describe randomization, and it explicitly classifies the study as single group. It therefore does not support a direct treatment-versus-control contrast.
There is no reported confidence interval or other measure of uncertainty for the clinical endpoint. In general, a confidence interval expresses the range of values reasonably compatible with data under a statistical model and indicates how precisely an effect has been estimated. Without the outcome counts and an estimate, neither the width nor the interpretation of such an interval can be assessed for this study. No p-value or adjusted analysis is reported in the registry record.
The posted safety figures describe adverse-event categories, not clinical efficacy. The record lists 22 at risk for serious adverse events and one affected, and 22 at risk for other adverse events and 22 affected. The serious-event term listed as most frequent is cardiac infarction at 4.5%. These safety entries do not fill the gap in the primary efficacy result; they address a different question. The record does not explain the relationship between the term-level percentage and the serious-event participant count.
The study status is terminated, but the reason is not reported in the registry record. That status does not by itself explain why the study ended or indicate whether the planned outcome was assessed. The record also does not provide an account of participant flow or explain whether the posted entries are complete. Accordingly, the most defensible reading is limited: a single-group phase 2 study planned an early RECIST-based clinical-response assessment of dasatinib, but the registry record does not report the efficacy findings needed to quantify or interpret that response.
9. Statistical Methods Explained
What does a single-group design estimate?
In a single-group study, participants receive the listed intervention, and outcomes are described within that group. This can document what was observed among treated participants, if outcome data are reported. It does not create a concurrent counterfactual group that represents what would have happened to comparable participants without the intervention. A randomized comparison can help address that question by assigning participants to groups under a specified process; this record does not describe such an assignment. Its allocation field is NA, and its design is classified as single group.
For this study, the listed intervention is open-label dasatinib. An outcome description in such a design would be a group-level observation, not by itself a treatment effect relative to a control. Other influences on disease course or measurement cannot be separated from treatment effects through a between-group comparison when no such group is reported. This is a general limitation of uncontrolled designs, not a claim about what happened to any participant in this study.
What does RECIST classification do?
RECIST provides rules for categorizing change in measurable lesions. Here, the registry description focuses on the longest diameter of the target lesion. It defines complete response as disappearance, partial response as a decrease of 30% or greater compared with baseline, and progressive disease as an increase of 20% or greater from the smallest diameter recorded since baseline or the appearance of a new lesion. Stable disease is the category when neither the stated shrinkage nor increase threshold is met.
Those rules make the endpoint operational: measurements are translated into defined clinical-response categories. But the rules are not data. To interpret the study, readers would also need the observed counts in the categories, information about who was assessed, and a clear description of how the analysis treated participants without an evaluable assessment. Those details are not reported in the registry record. The endpoint description also does not give lesion-measurement results or an estimated response proportion.
How should precision be considered?
Statistical precision describes how much uncertainty surrounds an estimate. A confidence interval is a common way to communicate that uncertainty: narrower intervals generally indicate greater precision, while wider intervals indicate less. It does not remove possible bias from study design, measurement, or missing information. In this study, no clinical-response estimate or confidence interval is reported, so its statistical precision cannot be assessed from the registry record.
The listed enrollment is 22, but enrollment is not necessarily the same as the number with an outcome assessment or the number analyzed. The primary-outcome description states that all patients who started treatment would be included. The actual count who started, the count with evaluable measurements, and any exclusions are not reported in the registry record. It would therefore be inappropriate to treat the enrollment figure as the outcome denominator.
What role does over-dispersion play?
Over-dispersion is a general issue for count outcomes: observed variability can exceed what a simple statistical model assumes. If that happens, methods that account for the extra variability may be more appropriate than methods that assume a narrower distribution. Whether over-dispersion is relevant depends on the outcome and model. The registry record does not report an analysis model, dispersion estimate, or model diagnostics for the primary endpoint. The endpoint is described as a number of participants and classified as binary in the record, but the response-category counts and analysis are absent. There is no basis for asserting that an over-dispersion adjustment was needed or used.
What can be inferred from the analysis listing?
The registry lists zero analyses. This means the record contains no listed analysis results; it does not establish whether analyses were conducted outside the registry or whether analyses were omitted. No p-value, confidence interval, adjusted estimate, or model specification for clinical efficacy is reported. The sponsor's own analysis cannot be compared with a recalculation because no efficacy summary statistics or sponsor analysis are listed. No recalculated efficacy result is available.
A sample-size illustration, when based on an observed effect, is a planning exercise rather than evidence that the study had a particular probability of finding a result. The stated illustration assumptions are a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation, with the effect to detect set as a stated fraction of the observed effect. Those assumptions do not describe this single-group study's allocation, and no observed primary effect is reported. Any such planning values should therefore not be read as observed power or as the study's original design justification. The registry record does not report the trial's sample-size justification.
Why does the assessment window matter?
The primary outcome is assessed at pre-surgery or 3 to 4 weeks of treatment. This identifies an early assessment point, but the record does not report how the timing was applied participant by participant. An early measurement can answer a question about short-term lesion change; it does not, by itself, establish how long a response lasts or what later outcomes occurred. Long-term outcomes, later follow-up, and their analysis are not reported in the registry record.
10. Multiplicity, Missing Data and Analysis Populations
The registry record identifies one primary outcome measure, Clinical Efficacy, and lists zero analyses. It does not report a statistical analysis plan, details of any secondary outcomes, or a strategy for handling multiple statistical tests. A multiplicity adjustment is used in some settings to account for the increased chance of a false-positive finding when several hypotheses are tested. Whether such an adjustment was planned or needed in this study is not reported in the registry record. The absence of listed analyses should not be interpreted as proof that no analyses were conducted.
The primary-outcome description defines the intended analysis population as all patients who started treatment. The record does not report how many patients started treatment, how many had an assessment, or how many were included in an analysis. It also does not report a missing-data method, rules for unevaluable lesions, or an account of withdrawals and exclusions. These details matter because missing outcome measurements can affect both the estimate and its precision, particularly if the availability of a measurement is related to a participant's clinical course.
Enrollment is listed as 22, but that figure does not establish the denominator for the response endpoint. It cannot be assumed that every enrolled participant started treatment or had an evaluable pre-surgery or early-treatment assessment. The record does not provide participant flow or enough information to determine whether the stated analysis population was implemented as planned.
The registry also does not report a protocol-based sample-size justification, an interim-analysis plan, or prespecified methods for handling deviations from the intended analysis population. These omissions limit assessment of how the study's analysis was planned and conducted. They do not show that a particular method was or was not used outside the registry record.
11. Safety Results
The registry reports serious adverse events as affected participants divided by participants at risk.
| Arm | Participants with serious adverse events | Participants at risk | Percentage |
|---|---|---|---|
| Dasatinib | 1 | 22 | 4.5% |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 5% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Dasatinib | 22 of 22 |
Most frequent serious adverse event terms
| Event term | Organ system | Dasatinib |
|---|---|---|
| Cardiac infarction | Cardiac disorders | 1 of 22 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Dasatinib |
|---|---|---|
| Pain | General disorders | 15 of 22 |
| AST, SGOT(serum glutamic oxaloacetic transaminase) | Metabolism and nutrition disorders | 11 of 22 |
| ALT, SGPT(serum glutamic pyruvic transaminase) | Metabolism and nutrition disorders | 9 of 22 |
| Calcium, serum-low (hypocalcemia) | Metabolism and nutrition disorders | 7 of 22 |
| Hemoglobin | Blood and lymphatic system disorders | 6 of 22 |
| Glucose, serum-high (hyperglycemia) | Metabolism and nutrition disorders | 5 of 22 |
| Fatigue (asthenia, lethargy, malaise) | General disorders | 4 of 22 |
| Nausea | Gastrointestinal disorders | 4 of 22 |
| Potassium, serum-low (hypokalemia) | Metabolism and nutrition disorders | 4 of 22 |
| Diarrhea | Gastrointestinal disorders | 3 of 22 |
Serious events with the highest arm-level rate: cardiac infarction (4.5%).
The safety entry lists 22 participants at risk for serious adverse events and one affected. For other adverse events, it lists 22 at risk and 22 affected. These are the registry's recorded counts for the named categories; they should not be combined into a total or assumed to represent separate, non-overlapping participants. A participant can be represented in more than one event category, and the record does not describe overlap or event-level detail.
The most frequent serious-event term listed is cardiac infarction, with a reported value of 4.5%. The record does not give a corresponding event count in that term listing, explain the calculation of the percentage, or report its uncertainty. The term-level percentage should not be substituted for the serious adverse-event count, and it does not describe clinical response.
These entries are descriptive safety information. They do not establish whether an event was caused by dasatinib, how severe or persistent it was, or how events were adjudicated. Such details are not reported in the registry record. The status of the study is terminated, but the reason for termination is not reported; the safety figures do not establish that safety events caused it.
12. What the Result Does, and Does Not, Mean
The registry record establishes that a phase 2, open-label, single-group study of dasatinib was registered for women with locally advanced triple-negative breast cancer who had not received prior treatment for their breast cancer. It describes an intended RECIST-based clinical-response assessment at pre-surgery or 3 to 4 weeks of treatment. It also lists safety counts and a serious-event term with a percentage.
It does not report the primary clinical-response counts or an efficacy analysis. As a result, the registry record cannot show how many participants experienced complete response, partial response, stable disease, or progressive disease. It cannot provide an estimate of response frequency or the precision of such an estimate. The listed enrollment of 22 is not an outcome count and should not be used as the denominator for a response calculation.
Even if a response estimate were available, the single-group design would describe outcomes within the treated group rather than estimate a randomized contrast with a concurrent control. An observed change in lesion size would not, by itself, identify the effect attributable to the intervention. The open-label design and the absence of reported information about measurement procedures also limit assessment of possible influences on outcome classification.
The safety entries do not resolve these efficacy uncertainties. They record adverse-event categories but do not establish causation, detail event timing, or explain the relationship between the serious-event term and the participant counts. The terminated status likewise does not reveal why the study ended or whether its intended assessments were completed.
Accordingly, the record supports a description of the study design, planned endpoint, and posted safety entries, but not a conclusion about the magnitude, precision, or comparative effect of dasatinib on clinical response. The reason for termination, participant flow, missing-data handling, and detailed analysis methods are not reported in the registry record.
13. Why This Trial Matters Statistically
This study illustrates why endpoint definitions and outcome results need to be read separately. The registry gives a detailed RECIST definition for clinical response, including the measurement basis and categories, but it does not report the counts assigned to those categories. A carefully specified endpoint makes an outcome interpretable only when the observed data and analysis are also available.
Its single-group design is another important statistical feature. It can support a descriptive account of outcomes among participants who received dasatinib, but it does not supply a concurrent control for estimating a treatment contrast. This distinction matters particularly when the study question is framed in terms of whether a treatment changes disease measurements. Without a comparison group, the design cannot isolate treatment-associated change from other possible influences.
The record also highlights the role of analysis-population information. It says that all patients who started treatment would be included, but does not report how many started, how many had an evaluable assessment, or how missing observations were handled. Enrollment alone is not enough to establish the denominator used for an endpoint. Clear participant flow and missing-data methods are needed to judge how representative an analysis may be.
Finally, a terminated status and safety listings do not substitute for primary efficacy results. The reason for termination is not reported, and the record lists no clinical efficacy analyses. Together, these features show why statistical interpretation depends not only on a planned question, but also on reported estimates, uncertainty, analysis methods, and participant accounting.
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.
Several limitations are specific to the information recorded for this study. The design is single group, with no concurrent comparator listed, so it cannot provide a randomized treatment contrast. The study is open-label, and the registry record does not describe masking or procedures that might limit influence on outcome assessment.
The primary endpoint is defined, but its observed results are not reported. There are no response-category counts, efficacy estimates, confidence intervals, or listed analyses. The registry lists enrollment of 22, but does not report the number who started treatment, the number assessed, or the number analyzed. The primary-outcome statement about including all patients who started treatment does not resolve those missing participant-flow details.
The assessment window is described as pre-surgery or 3 to 4 weeks of treatment, but the timing actually used for each participant is not reported. The record does not provide lesion-level measurements, rules for unevaluable assessments, missing-data methods, or longer-term outcome results. It also does not report a statistical analysis plan, multiplicity procedures, or a sample-size justification.
The study status is terminated, while the reason for termination is not reported in the registry record. The safety listing includes counts and a serious-event term, but does not supply event-level details, attribution, or an explanation of the term-level percentage. These omissions limit interpretation of both the planned efficacy assessment and the posted safety information. They do not, on their own, establish what analyses were conducted or why the study ended.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Efficacy Study of Dasatinib in Locally Advanced Triple-Negative Breast Cancer Patients — NCT00817531.
- Registry record last updated 2012-08-31; status last verified 2012-08.
- Results first posted 2012-07-17.
- 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.
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18. Record Summary
The registry describes a phase 2, open-label, single-group study of dasatinib / Sprycel 100 mg in previously untreated women with locally advanced triple-negative breast cancer. Enrollment is listed as 22; the study start is 2008-12, primary completion is 2011-02, and status is terminated.
The primary outcome is Clinical Efficacy, assessed by RECIST changes in the longest diameter of the target lesion at pre-surgery or 3 to 4 weeks of treatment. The record does not report primary-outcome counts or analyses. It states that all patients who started treatment would be included, but the number who started and the number analyzed are not reported in the registry record.
Safety entries list serious and other adverse-event counts and cardiac infarction at 4.5% as the most frequent serious-event term. The reason for termination, participant flow, missing-data methods, and detailed statistical analysis methods are not reported in the registry record.