Cetuximab and Cisplatin in Treating Patients With Advanced, Persistent, or Recurrent Cervical Cancer: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Cetuximab and Cisplatin in Treating Patients With Advanced, Persistent, or Recurrent Cervical Cancer (NCT00101192), a registered phase 2 study. The primary outcome is Tumor Response.

2. Clinical Question

3. Trial Design

This is a phase II trial of cetuximab in combination with cisplatin for patients with advanced, persistent, or recurrent carcinoma of the cervix. The registry lists the Gynecologic Oncology Group as sponsor and records the study as completed. Enrollment is 76; the recorded start is 2004-09 and primary completion is 2011-07.

Masking is listed as none. Allocation is not stated, and the record does not describe a randomized comparison. Although the trial evaluates the cetuximab–cisplatin combination, its posted safety group is titled “Cetuximab.” The registry does not give enough allocation detail to interpret that group as a separate randomized arm or to compare it with a control group.

The primary outcome is tumor response among eligible and evaluable participants. Its timeframe is up to 6 months from study entry. The record also lists progression-free survival and overall survival at 6 months after completion of treatment as secondary outcomes. It reports two outcome measures but no analyses. Protocol details such as the planned analysis methods, the definition of the analysis population beyond “eligible and evaluable,” and the handling of participants who could not be evaluated are not reported in the registry record.

The registry’s stated rationale describes cetuximab and cisplatin as a combination under study. That rationale is not a result. In particular, the design information alone does not show whether tumor response occurred, how often it occurred, or how precisely it was estimated.

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: Eligible and evaluable participants

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: Eligible and evaluable participants

6. Primary Endpoint

The registry lists the primary outcome as Tumor Response, measured over up to 6 months from study entry.

Tumor response is the primary endpoint. It classifies participants according to changes in measurable and nonmeasurable disease, new lesions, or the absence of repeat assessments. The registry specifies GOG RECIST criteria and a timeframe of up to 6 months from study entry. The listed population is eligible and evaluable participants.

A complete response requires disappearance of all target and nontarget lesions, with no new lesions, documented by two disease assessments at least 4 weeks apart. A partial response requires at least a 30% decrease in the sum of the longest dimensions of target measurable lesions from baseline, with no unequivocal progression of nontarget lesions and no new lesions. Increasing disease is defined by at least a 20% increase from the smallest sum of longest dimensions or the appearance of new lesions within 8 weeks of study entry. Stable disease does not meet the other response criteria. Indeterminate response applies when no repeat tumor assessment follows initiation of study therapy for reasons unrelated to disease symptoms or signs.

Response is a binary or categorical clinical outcome rather than a continuous measurement. It can describe whether participants met a prespecified disease-assessment category during the stated timeframe. However, the registry record does not report response counts or the result for this endpoint. The endpoint definition therefore clarifies what would count as response but does not establish how many participants met that definition.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

What does a binary response endpoint represent?

In general, a binary outcome records whether an individual meets a defined criterion or does not. Tumor response is based on disease-assessment categories defined by the registry’s GOG RECIST criteria. For a statistical summary, the number meeting the response definition is interpreted alongside the number assessed in the relevant population. The denominator matters because a count alone does not show how common the outcome was among those assessed.

The registry names eligible and evaluable participants as the primary-endpoint population, but it does not report how many participants were eligible and evaluable or how many met each response category. A response estimate and its precision therefore cannot be reconstructed from this record. The enrollment count of 76 should not be treated as the primary-endpoint denominator without evidence that all enrolled participants were evaluated.

Why does a confidence interval matter?

In general, a confidence interval expresses the statistical uncertainty around an estimate. It helps distinguish a point estimate from the range of values that remain compatible with the data under the method used. The width of an interval depends on factors including the amount of information and the observed outcome pattern. A narrow interval indicates greater precision than a wide interval, but neither an interval nor its width establishes clinical importance by itself.

No response estimate or confidence interval is reported in the registry record. Precision therefore cannot be assessed for the primary endpoint. A p-value, if available, would address a different question and would not replace the estimate or its uncertainty. The registry record reports no analyses, so it provides no inferential result to interpret.

What can an unrandomized design establish?

In general, a randomized comparison aims to balance prognostic factors between treatment groups through the assignment process. When a study does not report randomized allocation or a like-for-like control group, observed outcomes cannot be interpreted as a randomized estimate of the treatment contrast. A single group’s response experience, if reported, would describe that group under the study conditions; by itself it would not isolate the contribution of one intervention from other influences.

For this trial, allocation is not stated, and the registry explicitly indicates that the record is not a randomized comparison. The description of cetuximab with cisplatin identifies the combination under study, but does not supply an eligible comparator result. Comparative effectiveness methods cannot be inferred from the phase label or the trial purpose.

How should the safety counts be read?

In general, a count of participants affected is distinct from a count of event occurrences. A participant may experience more than one event, and a summary may count people, events, or both depending on its definition. The registry labels its figures as affected participants and supplies participants at risk for serious and other adverse events. The serious and other categories should be kept distinct; their counts should not be added or treated as mutually exclusive without an explicit definition.

The posted record lists 69 participants at risk for each category, with 33 affected by serious adverse events and 66 affected by other adverse events. It does not explain the relationship between those categories or provide a control group for a comparative safety analysis. The listed serious-event terms and percentages are descriptive registry entries, not adjusted comparisons.

What do the sample-size illustrations mean?

In general, a sample-size calculation for a future study uses assumptions about a target effect, significance level, allocation, and statistical method to estimate the number of participants needed for a chosen power. Such planning figures are conditional on those assumptions. They are not observed outcomes and do not show that a completed study had a particular probability of detecting an effect.

The planning description associated with this study specifies a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation, with planning effects expressed as fractions of an observed effect. Those are planning assumptions, not evidence of the trial’s own design. The registry record does not report a protocol sample-size justification. The stated number of analyses is 0, and no observed primary response effect is reported in the registry record, so the planning description cannot be used as a substitute for a trial result or as observed power.

For a count endpoint, over-dispersion is a general concern when the variability exceeds what a simple model assumes. It can make standard errors too small if not accounted for, leading to intervals that are too narrow and tests that are too optimistic. This trial’s primary outcome is a participant response classification, not a reported event-rate estimate with a dispersion parameter. Dispersion information is not reported in the registry record, and no model-based analysis is available to evaluate this issue.

10. Multiplicity, Missing Data and Analysis Populations

The registry lists tumor response as the primary outcome and progression-free survival and overall survival at 6 months after completion of treatment as secondary outcomes. Considering more than one outcome can raise multiplicity concerns: when several statistical tests are performed, the chance of at least one apparently unusual result may increase. In general, a prespecified analysis plan can state which outcomes are primary and whether any adjustment or hierarchical testing approach will be used. The adjustment strategy and statistical plan are not reported in the registry record.

The record reports 0 analyses. It does not provide test statistics, p-values, estimates, confidence intervals, or results for the primary or secondary outcomes. It is therefore not possible to determine whether multiplicity adjustments were applied, whether the outcomes were tested, or whether the analyses followed a prespecified order.

The primary population is described as eligible and evaluable participants, but the number in that population and the flow from enrollment to evaluation are not reported. The registry defines an indeterminate response category for participants without repeat tumor assessments for reasons unrelated to symptoms or signs of disease. It does not report how many participants were classified as indeterminate, how missing outcome assessments were handled in any analysis, or whether a sensitivity analysis was performed.

In general, missing outcome data can affect an estimate if the participants with missing assessments differ in outcome from those assessed. The direction and size of any such effect depend on the missingness pattern and the assumptions used in the analysis. Those details are not reported in the registry record. The available information does not support assumptions about the analysis population, missing-data method, or multiplicity control beyond the stated endpoint definitions.

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: thrombosis/thrombus/embolism (7.2%), renal failure (4.3%), death no ctcae term - disease progression nos (2.9%), nausea (2.9%), hemorrhage, gu - vagina (2.9%).

The registry’s adverse-event summary lists a Cetuximab group with 69 participants at risk for serious adverse events and 33 affected. It separately lists 69 participants at risk for other adverse events and 66 affected. These are participant counts as recorded, not a comparison between randomized groups. Allocation is not stated, and a like-for-like control group is not described.

The serious adverse-event terms with the largest listed percentages are thrombosis/thrombus/embolism at 7.2%, renal failure at 4.3%, death no CTCAE term – disease progression NOS at 2.9%, nausea at 2.9%, hemorrhage, GU – vagina at 2.9%, and infection with normal or grade 1 or 2 ANC: urinary tract NOS at 2.9%. These registry entries should be read as descriptive safety reporting. The record does not state the denominator used for each term or whether a participant could be represented under multiple terms.

Serious adverse events and other adverse events are separate summary categories. The registry does not explain whether the affected participants overlap, so the counts should not be combined. These entries alone do not establish a comparative safety effect or a causal relation.

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

The registry record establishes that a phase II study examined cetuximab with cisplatin for advanced, persistent, or recurrent cervical cancer, and that tumor response was the primary endpoint. It also defines how response categories were to be assigned and lists secondary survival outcomes. The record reports enrollment of 76 and provides adverse-event counts for a group titled Cetuximab.

Those details do not provide the primary efficacy result. The number of participants with a complete or partial response, the number evaluated, and an estimate of response precision are not reported in the registry record. The listed secondary outcomes have no posted results in the record. The study’s purpose and response criteria cannot be substituted for observed findings.

The safety entries describe reported affected-participant counts and serious-event terms. They do not provide a randomized control comparison, and allocation is not stated. Accordingly, the safety counts should not be interpreted as showing how the combination compares with another treatment or as establishing that an intervention caused a particular event.

More generally, a study result answers a specific question only in relation to its design, population, outcome definition, and analysis. Here, the registry supports a description of the study and its endpoint but not a quantified efficacy conclusion. It also does not report enough information to assess missing outcome data, the analysis population’s size, or statistical uncertainty. A planning illustration, where considered, addresses hypothetical sample requirements under assumptions; it does not supply a missing trial result or demonstrate observed power.

13. Why This Trial Matters Statistically

This trial is statistically instructive because it separates a clearly defined endpoint from the result needed to interpret that endpoint. The registry describes tumor response in detail, including complete, partial, stable, increasing, and indeterminate categories. Yet it does not report the response counts or the number of eligible and evaluable participants. A rigorous endpoint definition improves clarity about what should be measured, but it cannot convey the observed result without those data.

The record also highlights why enrollment and endpoint denominators should not be conflated. Enrollment is 76, while the primary population is eligible and evaluable participants; its size is not reported. Statistical interpretation depends on knowing which participants contributed to the estimate and how unassessed outcomes were handled.

Design context is equally important. The registry does not describe a randomized comparison, allocation is not stated, and no like-for-like control is identified. A treatment combination may be the focus of a phase II study, but the design information does not support interpreting its outcomes as a randomized contrast.

Finally, the safety record distinguishes serious from other adverse events and reports terms with percentages. These summaries are useful descriptive information, but they are not comparative estimates and their denominators are not reported by term. The trial therefore illustrates a general statistical lesson: endpoint definitions, denominators, design, uncertainty, and analysis details all contribute to interpretation. When registry results omit outcome estimates and analysis information, the scope of defensible conclusions remains limited.

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 registry record does not report the primary tumor-response result, including response counts, the number evaluated, or an uncertainty estimate. The endpoint population is described as eligible and evaluable, but its size and its relation to the enrollment of 76 are not specified. The secondary outcomes, progression-free survival and overall survival at 6 months after completion of treatment, also have no reported results.

Allocation is not stated, and the registry indicates that this is not a randomized comparison. The record therefore does not provide a like-for-like control basis for a comparative interpretation. It also does not report details of the statistical analysis plan, any covariate adjustment, the treatment of missing assessments, or any multiplicity procedure. The number of analyses is recorded as 0.

The safety summary lists 69 participants at risk and 33 affected for serious adverse events, and 69 at risk and 66 affected for other adverse events. The record does not state whether the affected groups overlap, explain the relationship between serious and other categories, or report the denominator underlying each serious-event term percentage. These limitations constrain interpretation of both the counts and percentages.

The registry’s planning description includes assumptions for sample-size illustrations, but it is not the trial’s own design justification. The record does not report a protocol sample-size rationale. Overall, the available information permits description of the study purpose, endpoint definition, and selected safety entries, but not a quantified efficacy assessment or a comparative treatment conclusion.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Cetuximab and Cisplatin in Treating Patients With Advanced, Persistent, or Recurrent Cervical Cancer — NCT00101192.
• Registry record last updated 2014-03-17; status last verified 2014-02.
• Results first posted 2014-03-17.
• 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.

18. Record Summary

NCT00101192 is a completed phase II study sponsored by the Gynecologic Oncology Group. It evaluates cetuximab with cisplatin for advanced, persistent, or recurrent cervical cancer. Enrollment is 76; the recorded start is 2004-09 and primary completion is 2011-07. Masking is listed as none.

The primary outcome is tumor response among eligible and evaluable participants, assessed by GOG RECIST criteria up to 6 months from study entry. The registry also lists progression-free survival and overall survival at 6 months after completion of treatment. The primary and secondary outcome results are not reported in the registry record, and the number of analyses is 0.

The safety summary lists 69 participants at risk for serious adverse events, with 33 affected, and 69 at risk for other adverse events, with 66 affected. Allocation is not stated, and the record does not describe a randomized control comparison. The available registry information supports a description of the design, endpoint, and selected safety entries, but not an efficacy estimate or comparative conclusion.