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 Study of Cetuximab With Radiation Followed by Consolidation Chemotherapy for NSCLC (NCT00492206), a na phase 2 study. The primary outcome is Overall Survival (OS).
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00492206 |
| Phase | Phase 2 |
| Condition | Non Small Cell Lung Cancer (NSCLC) |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 40 |
| Arms in the primary outcome | n/a |
| Lead sponsor | University of Pittsburgh |
| Results posted | Yes |
2. Clinical Question
Population
Patients with surgically unresectable stage IIIA or IIIB non-small cell lung cancer (NSCLC). The survival analysis included 38 patients; the registry record says two ineligible patients with advanced NSCLC were excluded from that analysis.
Intervention
The planned regimen combined cetuximab with external beam radiation, followed by consolidation chemotherapy with paclitaxel, carboplatin, and cetuximab. The regimen description specifies cetuximab at 400 mg/m2 IV in week 0, radiation during weeks 1 - 7, weekly cetuximab during weeks 1 - 7 and weeks 8 - 26, and carboplatin with paclitaxel every 3 weeks x 3 Cycles.
Comparator
There was no concurrent comparator group. The study is listed as single group, with allocation marked NA and masking marked NONE. It therefore does not provide a randomized, like-for-like comparison of the regimen against another treatment.
Primary question
The primary outcome was overall survival (OS), measured as a median in months with a 95% confidence interval, over a timeframe of up to 36 months. The registry record describes the outcome and analysis population but does not report the median OS estimate or its confidence interval.
In practical terms, the study asked how long patients in this single group lived after receiving the specified treatment sequence, as captured by the registry’s OS outcome. That is a descriptive question about outcomes among treated participants. Without a control group, the record cannot show whether observed survival differed from what would have occurred with another regimen or with no study treatment.
The registry record lists progression-free survival, best overall response rate, and EGFR gene mutation and Akt, pAkt, and MAPKinase among secondary outcomes. It does not include numerical results for those outcomes in the available information. Nor does the record state a comparative hypothesis or a treatment-effect target. The clinical question should therefore be read as a description of the study’s population, regimen, and outcome—not as evidence of comparative benefit.
3. Trial Design
This was a phase II, open-label, single-group study sponsored by the University of Pittsburgh. The registry lists a planned enrollment of 40 and the study status as completed. The recorded start was 2006-06, and primary completion was 2012-02. Allocation is marked NA and masking is marked NONE. These design features mean there was no randomized allocation and no masking of treatment assignment.
Participants had locally advanced NSCLC. The primary outcome entry specifies surgically unresectable stage IIIA or IIIB disease. The survival analysis population was N = 38 after excluding two ineligible patients with advanced NSCLC. The registry does not describe the eligibility criteria beyond the population description included in the outcome entry, so other details of who could enter the study are not reported in the registry record.
The regimen combined cetuximab with external beam radiation, followed by consolidation chemotherapy. The description gives an initial cetuximab dose of 400 mg/m2 IV in week 0, external beam radiation in weeks 1 - 7, and weekly cetuximab at 250 mg/m2 IV during weeks 1 - 7. It then describes weekly cetuximab at 250 mg/m2 IV during weeks 8 - 26 and carboplatin AUC = 6 IV with paclitaxel 200 mg/m2 IV every 3 weeks x 3 Cycles. This is the regimen description in the registry; adherence, dose modifications, and treatment completion are not reported in the registry record.
Overall survival was the primary outcome, reported in months as a median with a 95% confidence interval, with a timeframe of up to 36 months. The registry also names progression-free survival, best overall response rate, and biomarker outcomes as secondary outcomes. The numerical outcome results, detailed analytic methods, and any comparison with an external or historical group are not reported in the registry record. Because this was a single-group study, its design supports description of outcomes in the enrolled population but not a direct randomized comparison.
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: Non-Small Cell Lung Cancer, unresectable limited to Stage IIIA/B.
Overall Study
| Stage | Chest Radiotherapy + Cetuximab + Consolidation Therapy With ca |
|---|---|
| STARTED | 40 |
| COMPLETED | 40 |
| NOT COMPLETED | 0 |
Analysis population for the primary outcome, as defined in the registry: Patients with surgically unresectable stage IIIA or IIIB NSCLC. Survival analysis excluded the two ineligible patients with advanced NSCLC (N = 38).
5. Baseline Characteristics
The table reproduces the baseline characteristics posted in the registry, which describe the participants analysed at baseline and help show whether the randomized groups were comparable.
Population: Number of patients with surgically unresectable stage IIIA or IIIB NSCLC accrued
| Characteristic | Unit | Chest Radiotherapy + Cetuximab + Consolidation Therapy With ca |
|---|---|---|
| Participants analysed | 40 | |
| Age, Continuous | years | 67 (40 to 82) |
| Gender: Female | Participants | 14 |
| Gender: Male | Participants | 26 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 |
| Race (NIH/OMB): Asian | Participants | 0 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 |
| Race (NIH/OMB): Black or African American | Participants | 3 |
| Race (NIH/OMB): White | Participants | 37 |
| Race (NIH/OMB): More than one race | Participants | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 0 |
6. Primary Endpoint
The registry lists the primary outcome as Overall Survival (OS), measured over Up to 36 months.
| Element | Registry entry |
|---|---|
| Result type | Median |
| Measure of spread | 95% Confidence Interval |
| Unit | months |
| Endpoint classification | Time-to-Event Analysis |
Overall survival measures the time from a defined starting point to death from any cause. The registry identifies OS as the primary outcome and specifies a median in months with a 95% confidence interval, over a timeframe of up to 36 months. The starting point used to calculate survival is not described in the outcome entry, so it is not reported in the registry record.
The median is a summary of the time-to-event distribution: it marks the point at which half of the observed survival times lie on either side, subject to the way incomplete follow-up is handled. This is a general explanation of the statistic, not a description of unreported analysis details for this study. Time-to-event measures are useful when participants may have different follow-up lengths and when not every participant has experienced the event by the end of observation. A confidence interval expresses uncertainty around an estimated quantity; its width helps readers assess how precisely that quantity has been estimated.
The registry record gives the outcome type, unit, interval type, timeframe, and analysis population, but does not include the median OS value or the confidence interval limits. Consequently, the magnitude and precision of the primary endpoint cannot be assessed from the registry information. The outcome definition alone does not establish whether survival was longer or shorter than under another treatment, particularly because the study has no concurrent comparator.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry identifies median overall survival as the primary outcome and specifies a 95% confidence interval and a timeframe of up to 36 months. It also specifies that the survival analysis excluded two ineligible patients with advanced NSCLC, leaving N = 38 for that analysis. These details establish what outcome was planned for reporting and which population was included in the listed survival analysis.
However, the record does not report the median OS estimate or the confidence interval limits. There is therefore no numerical primary result in the registry information to interpret for its magnitude or precision. The record also does not include a sponsor-reported hazard ratio in the registry record for this analysis. Without an outcome estimate, confidence interval, or hazard ratio, it is not possible to characterize the direction or size of an observed survival result from this registry entry.
The study was single group, open label, and had no randomized allocation. That design is relevant to interpretation even if outcome estimates were available: outcomes among participants receiving a regimen do not, by themselves, identify what would have happened to comparable participants under another regimen. Differences in patient characteristics, care, and follow-up can affect comparisons made across separate groups or studies. This is a general limitation of uncontrolled treatment descriptions, not a finding about a specific source of bias in this trial.
The planned enrollment was 40, while the listed survival analysis included N = 38. The record attributes the exclusion to two ineligible patients with advanced NSCLC. The registry does not say how many participants contributed to secondary outcome analyses, whether participants had incomplete follow-up, or how missing outcome information was handled. Those omissions matter because the analyzed population and follow-up completeness help determine how representative an estimate is of all enrolled participants.
Safety information should also be interpreted descriptively. The record lists 11 participants affected by serious adverse events among 40 at risk and 38 affected by other adverse events among 40 at risk. It lists several serious adverse event terms with percentages, but does not specify in this entry whether those percentages represent participants or event counts. The recorded figures do not establish that an event was caused by the study regimen, and the registry does not provide a death count in the adverse-event group entry.
Overall, the record supports a description of study design, treatment sequence, population, and some adverse-event counts. It does not provide the numerical primary endpoint result or the details needed to judge the precision of survival estimates, secondary outcomes, or missing data. Conclusions about comparative effects are not supported by this single-group design and the outcome information reported in the registry.
9. Statistical Methods Explained
The registry lists overall survival as a median time-to-event outcome and specifies a 95% confidence interval. These choices describe how the primary outcome is represented, but the numerical estimate and interval limits are not reported in the registry record. The study is listed as single group, with allocation marked NA and masking marked NONE. The methods discussion below explains the statistical concepts relevant to those entries; it does not infer analysis procedures that are absent from the record.
What does a median survival time describe?
For a time-to-event outcome, the median is a location summary of the distribution of observed times until the event. Here the event is death from any cause, as defined by the general meaning of overall survival. Unlike a simple average, the median is less affected by particularly long or short observed times. In clinical studies, some participants may still be alive when their recorded follow-up ends. General time-to-event methods can incorporate such incomplete event times, but the registry entry does not describe the method used to estimate median OS in this study. It is therefore not appropriate to assume a particular estimator or censoring rule.
The record gives a timeframe of up to 36 months. That indicates the timeframe attached to the outcome entry; it does not establish that every participant was followed for the same duration or that every participant had complete outcome information. Follow-up distribution, censoring details, and the number of deaths are not reported in the registry record.
How should a confidence interval be read?
A confidence interval communicates uncertainty around an estimated quantity. In general, an interval with narrower limits indicates greater statistical precision than a wider interval, while an interval with wider limits indicates more uncertainty. The interval does not remove possible bias from selection, measurement, or study design. It also does not turn a single-group estimate into a treatment comparison. Although the primary outcome entry specifies a 95% confidence interval, neither its bounds nor the estimate it would accompany is reported in the registry record. Its precision therefore cannot be evaluated from the available entry.
What can a single-group design estimate?
A single-group study can describe outcomes among participants who received the regimen and met the analysis criteria. It lacks an internal untreated or alternative-treatment group that would provide a contemporaneous estimate of outcomes under a different treatment strategy. As a general statistical matter, comparisons with external groups can be affected by differences in patient composition, eligibility, care, and outcome ascertainment. The registry lists no randomized comparison, and the record does not report an external comparison. The trial’s design therefore does not support a direct estimate of a causal treatment contrast from the information recorded.
Open-label status means masking was not used, as also indicated by masking marked NONE. General concerns about unmasked studies can include differences in treatment delivery, follow-up, or assessment. Their relevance depends on the outcome and study procedures. The registry does not report procedures for outcome adjudication, assessment masking, or efforts to reduce measurement bias, so no particular safeguard or bias can be attributed to this trial from the record.
What do the sample-size illustrations mean?
The planning illustrations use a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. For time-to-event outcomes, they express the total number of events using the Schoenfeld approach; other illustrations express participants per arm. The effect to detect is defined as a stated fraction of the observed effect. These figures are planning illustrations based on the observed effect, not the trial’s own design justification and not observed power. Their hypothetical two-arm allocation does not change the actual design: this study is recorded as single group and has no randomized comparison.
The registry does not report the trial’s sample-size justification, the assumptions used to plan enrollment, or a planned event target. It also does not give the numerical observed effect needed to evaluate a planning illustration. The illustration assumptions should therefore not be mistaken for the protocol’s design assumptions or for evidence about the probability that the study detected an effect.
What do hazard ratios and other analyses contribute?
A hazard ratio is a relative time-to-event measure that compares event rates over follow-up under a model. General interpretation depends on the comparison being made, the model assumptions, and the participants and events included. A hazard ratio is not the same quantity as a difference between median survival times. The method note for this analysis says that only sponsor-reported hazard ratios are used for time-to-event interpretation; a hazard ratio is not included in the registry information. The number of analyses is recorded as 0, and detailed analysis methods are not reported in the registry record.
The record names progression-free survival, best overall response rate, and EGFR gene mutation and Akt, pAkt, and MAPKinase among secondary outcomes. Their definitions, numerical estimates, confidence intervals, and analytic populations are not included in the information available. It is not possible to determine from the registry entry whether these outcomes were tested with particular models or whether any adjustments were made for multiple testing.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists several secondary outcomes in addition to overall survival: progression-free survival, best overall response rate, and EGFR gene mutation and Akt, pAkt, and MAPKinase. It also records four outcome measures and zero analyses. The entry does not provide the numerical secondary outcome results or describe a statistical analysis plan. Whether formal hypothesis tests were conducted for these outcomes, and how such tests were handled, is not reported in the registry record.
When a study assesses multiple outcomes or performs multiple statistical tests, the chance of at least one apparently unusual result can increase if each test is interpreted separately. Statistical approaches can address multiplicity, but the appropriate approach depends on the questions and analysis plan. The registry record does not report a multiplicity adjustment or explain whether any outcomes were treated as exploratory. It would therefore be inappropriate to infer either that multiplicity was controlled or that it was ignored in the actual study.
The primary outcome entry identifies a survival analysis population of N = 38, after two ineligible patients with advanced NSCLC were excluded from the analysis. The record does not say how missing data, incomplete follow-up, or censoring were handled. It also does not identify the analysis populations for the secondary outcomes, or whether the analysis population included everyone enrolled, everyone treated, or another defined group. The total planned enrollment is 40, but that figure alone does not resolve the disposition or outcome availability of every participant.
Interim analyses, stopping rules, protocol deviations, and the handling of participants who discontinued treatment are not reported in the registry record. Their absence from the entry should not be read as evidence that such procedures were or were not used. These reporting gaps limit assessment of analysis choices, participant flow, and the possible influence of missing information on the reported results.
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 |
|---|---|---|---|
| Chest Radiotherapy + Cetuximab + Consolidation Therapy With ca | 11 | 40 | 27.5% |
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 |
|---|---|
| Chest Radiotherapy + Cetuximab + Consolidation Therapy With ca | 38 of 40 |
Most frequent serious adverse event terms
| Event term | Organ system | Chest Radiotherapy + Cetuximab + Consolidation Therapy With ca |
|---|---|---|
| Neutrophils/granulocytes (ANC/AGC) | Blood and lymphatic system disorders | 8 of 40 |
| Dyspnea (shortness of breath) | Respiratory, thoracic and mediastinal disorders | 7 of 40 |
| Leukocytes (total WBC) | Blood and lymphatic system disorders | 4 of 40 |
| Hypotension | Cardiac disorders | 2 of 40 |
| Hypoxia | Respiratory, thoracic and mediastinal disorders | 2 of 40 |
| Pain, Abdomen NOS | General disorders | 2 of 40 |
| Supraventricular and nodal arrhythmia, Atrial fibrillation | Cardiac disorders | 2 of 40 |
| Allergic reaction/hypersensitivity (including drug fever) | Immune system disorders | 1 of 40 |
| Constitutional Symptoms - Other (Specify, __) | General disorders | 1 of 40 |
| Muscle weakness, generalized or specific area (not due to neuropathy), Extraocular | Musculoskeletal and connective tissue disorders | 1 of 40 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Chest Radiotherapy + Cetuximab + Consolidation Therapy With ca |
|---|---|---|
| Rash: acne/acneiform | Skin and subcutaneous tissue disorders | 31 of 40 |
| Cough | Respiratory, thoracic and mediastinal disorders | 31 of 40 |
| Fatigue (asthenia, lethargy, malaise) | General disorders | 29 of 40 |
| Dyspnea (shortness of breath) | Respiratory, thoracic and mediastinal disorders | 25 of 40 |
| Leukocytes (total WBC) | Blood and lymphatic system disorders | 24 of 40 |
| Nausea | Gastrointestinal disorders | 23 of 40 |
| Anorexia | Gastrointestinal disorders | 21 of 40 |
| Neutrophils/granulocytes (ANC/AGC) | Blood and lymphatic system disorders | 20 of 40 |
| Dysphagia (difficulty swallowing) | Gastrointestinal disorders | 16 of 40 |
| Rash/desquamation | Skin and subcutaneous tissue disorders | 14 of 40 |
Serious events with the highest arm-level rate: neutrophils/granulocytes (anc/agc) (20.0%), dyspnea (shortness of breath) (17.5%), leukocytes (total wbc) (10.0%), hypotension (5.0%), hypoxia (5.0%).
The adverse-event entry lists 40 participants at risk for serious adverse events, with 11 affected, and 40 at risk for other adverse events, with 38 affected. These are counts recorded for the treatment group, not a comparison with a control group. The adverse-event group title refers to chest radiotherapy, cetuximab, and consolidation therapy, but the registry entry does not provide a comparative safety analysis.
The listed serious adverse event terms and percentages are neutrophils/granulocytes (ANC/AGC), 20.0%; dyspnea (shortness of breath), 17.5%; leukocytes (total WBC), 10.0%; hypotension, 5.0%; hypoxia, 5.0%; and pain, abdomen NOS, 5.0%. The registry entry does not specify whether these percentages count participants with each term or event occurrences, so they should not be interpreted as participant-level risks without that information. The listed terms also do not establish whether events were judged related to treatment.
The deaths field is not populated in the adverse-event entry; a death count is therefore not reported in the registry record. Adverse-event counts describe what the registry records for the study group, but they do not by themselves determine causation or permit a comparison of safety against another treatment. Details such as event timing, severity grading beyond the serious classification, and the handling of repeated events are not reported in the registry record.
12. What the Result Does, and Does Not, Mean
The registry record establishes that a phase II, open-label, single-group study evaluated a regimen combining cetuximab and external beam radiation followed by consolidation chemotherapy in patients with locally advanced NSCLC. It defines overall survival as the primary outcome, gives the intended timeframe as up to 36 months, and identifies a survival analysis population of N = 38 after excluding two ineligible patients with advanced NSCLC. These are useful details about the study’s design and outcome population.
The record does not report the median overall survival estimate or its 95% confidence interval. As a result, it does not supply the primary outcome magnitude or its statistical precision. It also does not provide numerical results for the named secondary outcomes. The absence of those estimates in the registry entry cannot be treated as evidence of a particular outcome; it means the outcomes cannot be interpreted numerically from this record.
Because the study has no concurrent comparator, its design cannot determine how outcomes under this regimen compare with outcomes under another treatment. A single-group result, even when fully reported, is descriptive unless a valid comparison is available and its assumptions are defensible. This is a general statistical distinction between describing outcomes in a treated cohort and estimating a comparative treatment effect.
The adverse-event entry reports affected-participant counts and several serious adverse-event terms with percentages. Those figures should be read as registry descriptions, not as proof that the regimen caused the events or as evidence of relative safety. The record does not give a death count in that entry, clarify the denominator for each listed percentage, or report comparative safety results.
Accordingly, the registry information supports a limited account of the trial’s population, regimen, design, primary outcome definition, and recorded adverse-event counts. It does not support a conclusion about the size or precision of the survival outcome, the comparative effect of treatment, or the balance of benefits and harms. Missing result details should be distinguished from negative results: the registry entry does not report the numerical primary result, rather than reporting that the result was null.
13. Why This Trial Matters Statistically
This trial is statistically notable because the registry pairs a clinically important time-to-event endpoint with a single-group design. Overall survival can describe how long participants in the study group lived, but a treatment effect requires a comparison that estimates outcomes under an alternative strategy. With no randomized comparator, the study cannot itself separate the regimen’s contribution from other influences on survival.
The outcome entry also identifies an analysis population of N = 38 after excluding two ineligible patients with advanced NSCLC from the survival analysis, while planned enrollment was 40. Reporting the analysis population helps readers understand which participants contributed to the stated endpoint. At the same time, the registry does not provide the median OS estimate, confidence interval limits, or further details of follow-up and missing data. That combination illustrates why a clearly named endpoint is not enough to assess a result: readers also need the estimate, its uncertainty, and an account of who contributed data.
The record lists serious and other adverse-event counts, but those counts are not a substitute for a comparative safety analysis. Without a control group and enough detail about the event definitions and denominators, the entry cannot establish relative event rates or attribute events to treatment. This is a general issue in interpreting safety data from uncontrolled studies.
The sample-size illustrations are another reason to distinguish planning from evidence. Their stated assumptions describe hypothetical planning calculations, not the trial’s documented design rationale and not observed power. In a single-group trial, an illustration based on equal allocation between two arms does not describe the actual allocation structure. The statistical value of the record therefore lies mainly in clarifying the design and exposing the limits on interpretation, rather than in establishing a comparative treatment estimate.
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 principal limitation is the single-group design. Allocation is marked NA, masking is marked NONE, and there is no concurrent control group. As a result, outcomes among participants in the study group cannot be directly compared with outcomes under another treatment within the trial. Any external comparison would require information and assumptions not reported in the registry record.
The primary outcome is identified as median overall survival with a 95% confidence interval, but neither the median nor the interval limits are reported. Follow-up is described as up to 36 months, yet the record does not give follow-up distribution, event counts, or censoring details. The starting point for measuring OS is not specified in the outcome entry. These omissions prevent assessment of the primary estimate’s magnitude, precision, and analytic basis.
The survival analysis excluded two ineligible patients with advanced NSCLC and included N = 38. The registry does not describe additional exclusions, treatment completion, dose changes, or the analysis populations for secondary outcomes. Missing data and incomplete follow-up handling are not reported. The named secondary outcomes also lack numerical results and detailed definitions in the information available.
The serious adverse-event entry lists 11 affected participants among 40 at risk, and the other adverse-event entry lists 38 affected among 40 at risk. For the serious adverse event terms, the registry gives percentages without specifying whether the percentage denominator is participants or event occurrences. The deaths field is not populated. These reporting limits make the safety figures descriptive but difficult to interpret in detail.
The registry does not report the sample-size justification, interim analyses, stopping rules, or a detailed statistical plan. It does not state whether multiplicity adjustments were used. These omissions do not establish what procedures the investigators used; they limit what can be concluded from the registry record.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Study of Cetuximab With Radiation Followed by Consolidation Chemotherapy for NSCLC — NCT00492206.
- Registry record last updated 2017-02-01; status last verified 2016-12.
- Results first posted 2017-02-01.
- 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 completed, phase II, open-label, single-group study sponsored by the University of Pittsburgh, with planned enrollment of 40. It evaluated cetuximab with external beam radiation followed by consolidation chemotherapy in patients with locally advanced NSCLC. The primary outcome was overall survival, expressed as a median in months with a 95% confidence interval and a timeframe of up to 36 months.
The listed survival analysis excluded two ineligible patients with advanced NSCLC and included N = 38. The registry record does not report the median OS estimate or confidence interval limits, and it provides no numerical results for the listed secondary outcomes. Adverse-event entries record 11 participants affected by serious adverse events and 38 affected by other adverse events among 40 at risk in each category. The record offers no randomized comparison, so it describes outcomes in a study group rather than a comparative treatment effect.