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 Identification of Gene Expression Signature for Panitumumab Sensitivity in Untreated Locally Advanced SCCHN (NCT01305772), a non-randomized phase 2 study. The primary outcome is Change in Tumor (Primary Tumor and Lymph Node) Response and Progression Between Pre- and Post- Panitumumab Therapy.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01305772 |
| Phase | Phase 2 |
| Condition | Squamous Cell Carcinoma of the Head and Neck |
| Allocation | Non-Randomized |
| Design model | Parallel |
| Masking | None (open label) |
| Enrollment | 6 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Neal Ready |
| Results posted | Yes |
2. Clinical Question
Population
People with untreated, locally advanced squamous cell cancer of the head and neck that could be treated with surgery and/or radiation therapy. The registry describes the need for fresh frozen tumor tissue for genomic analysis before panitumumab; if it was not available at consent, a biopsy was required. The recorded enrollment was 6.
Intervention
Panitumumab was added to standard adjuvant or primary radiation therapy. One group underwent surgery followed by radiation therapy with panitumumab; the other received radiation therapy with panitumumab without surgery.
Comparator
The groups were defined by treatment pathway, not by random assignment. The registry explicitly identifies the study as nonrandomized, so these groups do not constitute a like-for-like control comparison.
Primary question
The study aimed to identify a gene-expression signature associated with response to panitumumab. The primary outcome concerned change in tumor and lymph-node response or progression between baseline and 2 years, assessed using imaging and/or direct measurements before and after panitumumab.
The clinical question combines a biomarker aim with an assessment of tumor response. A gene-expression signature would be useful for this research question only if the measured expression pattern could be related to how tumors changed during treatment. The registry describes response assessment using the largest percentage change among PET activity, radiologic measurements, and direct measurements of tumor or lymph node. It says measurement followed the same unidimensional approach as RECIST 1.1.
The record does not report primary-outcome results. It states that only 2 of the 6 subjects had tissue collected after the first panitumumab dose, and that the biopsy procedure was removed by amendment because of potential participant risk. Consequently, the posted record does not provide an estimate of tumor response or evidence identifying a predictive gene-expression signature. The study's design also does not support treating the surgery and radiation-only groups as randomized treatment alternatives.
3. Trial Design
This was a phase 2, parallel-group, nonrandomized study with no masking. The registry lists an enrollment of 6 and a status of terminated. Its recorded start was 2011-01 and its primary completion was 2012-03. The condition was squamous cell carcinoma of the head and neck.
Both treatment pathways included panitumumab and radiation therapy. The surgery group underwent surgery after research PET/CT scans and then received radiation therapy with panitumumab. The radiation-therapy group received radiation therapy with panitumumab and did not undergo surgery. The distinction between pathways is clinically relevant, but participants were not allocated at random. The registry cautions that the arms are not a like-for-like control comparison. Differences between their outcomes, if any were reported, could not automatically be attributed to the treatment pathway.
The study's central objective was to identify a gene-expression signature for sensitivity to panitumumab in untreated locally advanced disease. Fresh frozen tumor tissue was required for genomic analysis before therapy; when such tissue was unavailable at consent, a biopsy was required. The primary outcome was described over baseline to 2 years and was intended to assess response and progression using imaging and/or direct tumor and lymph-node measurements.
The registry lists 9-month progression-free survival and 9-month overall survival as secondary outcomes. It does not report results for the primary outcome, and the record's analysis count is 0. Detailed statistical methods, including an analysis plan, are not reported in the registry record. The reason given for the lack of primary-outcome results is that only 2 of the 6 subjects had tissue collected after the first panitumumab dose; the biopsy procedure was amended out because of potential safety risk.
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: All patients had successful genomic screening and RNA extraction/quality control.
Overall Study
| Stage | Radiation Therapy | Surgery |
|---|---|---|
| STARTED | 5 | 1 |
| Genomic Screening + Biopsy #1 | 5 | 1 |
| Research PET/CT #1 | 5 | 1 |
| Panitumumab Dose #1 | 5 | 1 |
| Research PET/CT #2 | 5 | 1 |
| Surgery/Biopsy #2 | 1 | 1 |
| RT + Panitumumab Dose #2 / #3 | 5 | 1 |
| COMPLETED | 5 | 1 |
| NOT COMPLETED | 0 | 0 |
Analysis population for the primary outcome, as defined in the registry: No results will be reported for the primary outcome measure as only 2 of the 6 subjects had tissue collected after the first dose of panitumumab due to safety risk to the subject.
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 | Radiation Therapy | Surgery | Total |
|---|---|---|---|---|
| Participants analysed | 5 | 1 | 6 | |
| Age, Continuous | years | 64.60 (SD 6.66) | 69 (SD NA) | 65.33 (SD 6.22) |
| Sex: Female, Male: Female | Participants | 0 | 0 | 0 |
| Sex: Female, Male: Male | Participants | 5 | 1 | 6 |
6. Primary Endpoint
The registry lists the primary outcome as Change in Tumor (Primary Tumor and Lymph Node) Response and Progression Between Pre- and Post- Panitumumab Therapy, measured over Baseline to 2 years.
| Element | Registry entry |
|---|---|
| Result type | N/A |
| Measure of spread | not applicable |
| Unit | not stated |
| Endpoint classification | not reduced to a single comparison |
The primary outcome was change in response and progression in the primary tumor and lymph nodes, assessed from baseline to 2 years. The registry describes a gene-expression signature as the target: the study sought to determine whether tumor gene-expression patterns could identify sensitivity to panitumumab. Such a signature is a biomarker question, not simply a measure of whether a tumor changed. It requires expression information that can be interpreted alongside treatment response.
Response and progression were assessed using the largest percentage change among three possible sources: pre-treatment PET scan activity, pre- and post-treatment radiologic measurements, and pre- and post-treatment direct measurements of the tumor or lymph node. The record says the measurements used changes in only the largest diameter, in the same manner as RECIST 1.1. Thus, the endpoint was intended to capture tumor change using a unidimensional measurement approach, with imaging and direct examination as possible inputs.
The registry states that no primary-outcome results will be reported because only 2 of the 6 subjects had tissue collected after the first panitumumab dose. It also says the biopsy procedure was removed because of potential risk to participants. The record therefore does not give an observed response estimate, a gene-expression signature, or a quantified association between expression and response. The rationale for choosing this endpoint beyond the stated biomarker aim is not reported in the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The central interpretive fact is that the registry reports no results for the primary outcome. The study aimed to connect tumor gene expression with response to panitumumab, but the record says only 2 of the 6 subjects had tissue collected after the first dose. It attributes the absence of primary-outcome results to this limitation and notes that the biopsy procedure was removed by amendment because of potential participant risk. There is therefore no posted primary-outcome estimate from which to judge the amount or precision of tumor change.
The registry lists three outcome measures, including the primary measure and secondary measures of 9-month progression-free survival and 9-month overall survival. It does not provide results for those survival outcomes in the registry record recorded for this analysis. The absence of posted outcome estimates means that no effect size, confidence interval, or test statistic can be interpreted for the primary question. Statistical significance, uncertainty around an effect, and the direction or magnitude of a treatment response cannot be inferred from the study aim or design.
The adverse-event record reports serious adverse events in 0 of 5 participants at risk in the radiation-therapy group and 0 of 1 in the surgery group. It also records other adverse events for 5 of 5 and 1 of 1, respectively. These are descriptive counts from the registry, not a comparative safety analysis. The groups are nonrandomized, and the surgery group is small; the counts do not establish that the pathways have equivalent safety profiles. Death counts are not reported in the registry record.
The group descriptions should not be read as a randomized contrast. Participants received different treatment pathways, and assignment was nonrandomized. A difference between groups could reflect factors related to the selected pathway or the participants, rather than the effect of surgery or radiation. In addition, the registry reports no analyses, and no adjusted comparisons are available in the record.
Overall, the posted data document the study's design, its intended biomarker and response question, the reason primary results were not reported, and adverse-event counts. They do not quantify treatment efficacy, establish a predictive gene-expression signature, or permit a reliable comparison of the treatment groups. Any broader conclusion would go beyond the results reported in the registry record.
9. Statistical Methods Explained
The statistical interpretation is limited by what the registry record reports. It describes the design and endpoint, but it does not report primary-outcome results or an analysis plan. No outcome estimates, confidence intervals, p-values, or adjusted comparisons are included in the registry record recorded for this analysis. Without those results, there is no numerical estimate of tumor response to interpret and no measure of statistical precision for the primary question.
What does a confidence interval communicate?
General statistical explanation: a confidence interval expresses the uncertainty around an estimated quantity under a specified statistical procedure. A narrow interval generally indicates greater precision than a wide interval, while the interval's location helps show which values are compatible with the data and method. An interval is not a guarantee that the true value lies within its endpoints. No confidence interval for the primary outcome is reported in the registry record, so precision cannot be assessed for the intended response or biomarker relationship.
Why does the nonrandomized design matter?
General statistical explanation: random allocation helps balance, on average, both measured and unmeasured participant characteristics between treatment groups. Without randomization, the groups may differ in ways that influence outcomes. This study's groups were based on different pathways: surgery followed by radiation therapy with panitumumab, or radiation therapy with panitumumab without surgery. The registry identifies allocation as nonrandomized and explicitly cautions that the arms are not a like-for-like control comparison. Consequently, a group contrast would not by itself isolate the effect of surgery, radiation, or panitumumab.
The parallel structure means the registry describes separate groups rather than a crossover sequence. No masking was used. These design labels describe how the study was organized; they do not compensate for the absence of reported primary outcomes or establish that outcome assessment was free from bias. Further information about assessor procedures is not reported in the registry record.
How should the tumor measurement approach be understood?
The registry says response and progression were assessed using the largest percentage change from among PET activity, radiologic measurement, and direct measurement of tumor or lymph node before and after panitumumab. It describes changes in only the largest diameter, in the same manner as RECIST 1.1. General statistical explanation: reducing a lesion measurement to a single dimension can make repeated assessment more standardized, but it does not capture every aspect of tumor biology. The registry does not report the precise rule used to choose among the different sources of measurement, or any results from applying the approach.
The stated endpoint also links response measurement to a gene-expression objective. A predictive signature requires a relationship between a measured biomarker and a subsequent outcome. The record's explanation is that post-dose tissue was collected for only 2 of the 6 subjects and that the biopsy procedure was removed due to potential risk. It does not describe a complete biomarker analysis, an estimated expression-response association, or the methods that would have been used to validate a signature.
What do the planning assumptions mean?
General statistical explanation: a sample-size calculation is a planning exercise that depends on assumptions about the effect to detect, variability, allocation, and the chosen error rate. The registry's planning illustration is described as using a two-sided significance level of 0.05, equal allocation, and a normal approximation, with the target effect expressed as a stated fraction of the observed effect. For time-to-event outcomes, the planning quantity is the total number of events; for other outcomes, it is participants per arm. These are planning illustrations, not observed power and not evidence that the enrolled study had adequate power. The registry does not report the trial's own design justification, and no numeric planning estimates are available in the record.
General statistical explanation: over-dispersion occurs when outcome variability is greater than a model assumes, which can make standard errors too small if the extra variability is ignored. The registry does not identify an outcome distribution or model that would allow assessment of over-dispersion, and no such adjustment is reported. This is a general consideration, not a claim that over-dispersion occurred in this study.
What can be concluded from the reported analyses?
The registry records zero analyses and gives no primary-outcome results. That means the posted record does not support interpretation of statistical tests, effect estimates, or model-based uncertainty for the main question. It does not establish whether analyses were conducted outside the registry record. Any more detailed statistical plan, including covariate adjustment, handling of repeated measurements, and model selection, is not reported in the registry record. The safe statistical reading is therefore descriptive: the intended endpoint and measurement approach are documented, but the planned relationship between gene expression and response is not quantified.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists a primary outcome concerning tumor and lymph-node response or progression from baseline to 2 years, alongside secondary outcomes of 9-month progression-free survival and 9-month overall survival. It also describes several possible sources for response assessment: PET activity, radiologic measurements, and direct measurements. These multiple outcomes and measurement sources raise a general statistical issue: when many outcomes or analyses are considered, the chance of at least one apparently notable finding can increase unless the analysis plan accounts for multiplicity. The registry record does not report a multiplicity strategy or specify how any competing measurements would be combined or prioritized in analysis.
No primary-outcome results are reported, and results for the secondary outcomes are not reported in the registry record recorded. The registry records zero analyses. It therefore does not provide enough information to assess whether multiplicity was addressed in an analysis or whether the secondary outcomes were intended as confirmatory or descriptive.
The record identifies a specific limitation for tissue collection: only 2 of the 6 subjects had tissue collected after the first dose of panitumumab, and the biopsy procedure was amended out because of potential participant risk. This explains why the primary results will not be reported, but it does not give a general missing-data analysis. Reasons for any other missing measurements, the amount of missing outcome data, and methods for handling missing data are not reported in the registry record.
The record does not specify an analysis population, such as an intention-to-treat or per-protocol population, nor does it describe eligibility for any outcome analysis. It also does not report exclusions, imputation methods, or sensitivity analyses. Those omissions should not be filled by assumption: the available record supports neither a claim that all enrolled participants were analyzed nor a claim that a particular missing-data method was used.
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 |
|---|---|---|---|
| Radiation Therapy | 0 | 5 | 0.0% |
| Surgery | 0 | 1 | 0.0% |
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 |
|---|---|
| Radiation Therapy | 5 of 5 |
| Surgery | 1 of 1 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Radiation Therapy | Surgery |
|---|---|---|---|
| Gastrointestinal disorders - Other, specify: Odonyphagia | Gastrointestinal disorders | 5 of 5 | 1 of 1 |
| Fatigue | General disorders | 5 of 5 | 1 of 1 |
| Weight loss | Investigations | 5 of 5 | 1 of 1 |
| Hypomagnesemia | Metabolism and nutrition disorders | 5 of 5 | 1 of 1 |
| Dysgeusia | Nervous system disorders | 5 of 5 | 1 of 1 |
| Constipation | Gastrointestinal disorders | 4 of 5 | 1 of 1 |
| Dry mouth | Gastrointestinal disorders | 5 of 5 | 0 of 1 |
| Dermatitis radiation | Injury, poisoning and procedural complications | 5 of 5 | 0 of 1 |
| Anorexia | Metabolism and nutrition disorders | 5 of 5 | 0 of 1 |
| Dehydration | Metabolism and nutrition disorders | 4 of 5 | 1 of 1 |
The registry reports serious adverse-event counts separately for the two groups. In the radiation-therapy group, 0 of 5 participants at risk had a recorded serious adverse event. In the surgery group, 0 of 1 participant at risk had a recorded serious adverse event. The record lists no serious-event terms. It also reports other adverse events in 5 of 5 participants at risk in the radiation-therapy group and 1 of 1 in the surgery group.
These figures are descriptive counts. They do not show the timing, duration, severity distribution, or relationship of the events to treatment, and those details are not reported in the registry record. The registry's deaths entries are not reported. A count of zero serious events in a group does not prove that an event is impossible or that the treatment pathway is free of risk. Conversely, the other-event counts alone do not indicate how severe the events were.
The two groups were nonrandomized and differ in treatment pathway, so their adverse-event counts should not be treated as a controlled comparison of safety. The surgery group has only 1 participant at risk, limiting what can be learned from its observed count. The record does not provide a formal statistical comparison or uncertainty estimates for safety outcomes.
12. What the Result Does, and Does Not, Mean
The record's main contribution is documentation of a phase 2 study designed to investigate whether a gene-expression signature could identify sensitivity to panitumumab in untreated locally advanced squamous cell cancer of the head and neck. It also describes how tumor response and progression were intended to be assessed. However, it reports no primary-outcome results, so it does not establish whether tumor measurements changed or whether any gene-expression pattern predicted response.
The stated reason for not reporting primary results is that only 2 of the 6 subjects had tissue collected after the first panitumumab dose. The study was amended to remove the biopsy procedure because of potential risk to participants. This is an important limitation for the biomarker objective, because the intended association depends on interpretable tissue and outcome information. The registry does not report an alternative analysis that resolves this limitation.
The posted record also does not establish a treatment effect. Both groups received panitumumab with radiation therapy, with surgery in one pathway, and allocation was nonrandomized. The registry cautions that the arms are not a like-for-like control comparison. No conclusion about the contribution of panitumumab, surgery, or radiation can be drawn from the reported adverse-event counts or from the study's stated aims.
The safety entries document recorded event counts, not a full assessment of comparative risk. They should be interpreted alongside the small group sizes and the lack of random allocation, and not as proof of safety or equivalence. The record does not report deaths or statistical safety comparisons.
Thus, the study's registry entry communicates an intended biomarker and response investigation, a tissue-collection problem that prevented primary results from being reported, and limited descriptive adverse-event information. It does not provide an efficacy estimate, validate a predictive signature, or demonstrate that one treatment pathway is superior to another. Those conclusions would require evidence not reported in the registry record.
13. Why This Trial Matters Statistically
This trial is statistically notable because its central question depends on connecting a biomarker with a clinical response, yet the registry reports no primary-outcome results. The record explains that only 2 of the 6 subjects had tissue collected after the first panitumumab dose. It also documents a protocol amendment removing the biopsy procedure because of potential participant risk. That situation illustrates a practical challenge in biomarker research: the data needed to evaluate a biological hypothesis must be collected in a way that is feasible and acceptable from a safety perspective.
The design also highlights the distinction between a treatment description and a controlled treatment comparison. The study had a surgery pathway and a radiation-only pathway, both with panitumumab, but allocation was nonrandomized. As the registry cautions, the arms are not a like-for-like control comparison. Statistical adjustment, even if it had been reported, would not automatically remove all bias from nonrandom treatment assignment.
The intended endpoint combined several possible measurement sources and focused on the largest diameter, following the same manner as RECIST 1.1. This makes the endpoint definition important: readers need to know how measurements are selected and interpreted before an estimate can be understood. The registry describes the approach, but provides no outcome estimate or detailed analysis methods.
Finally, the record is a reminder that an outcome's presence in a registry does not mean results are available. The primary question and secondary survival measures are listed, but the record reports no analyses and no primary results. The information that remains is useful for understanding the research question, design, and limitations, while making clear that the intended biomarker finding cannot be evaluated from the posted results.
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 primary limitation is the absence of reported primary-outcome results. The registry states that only 2 of the 6 subjects had tissue collected after the first panitumumab dose and that the biopsy procedure was removed because of potential risk. It does not report a gene-expression signature, response estimate, or association between expression and response. The listed secondary outcomes are 9-month progression-free survival and 9-month overall survival, but results for them are not reported in the record.
The study was nonrandomized and had no masking. The treatment pathways differed, and the registry cautions that the arms are not a like-for-like control comparison. Accordingly, any apparent difference between groups would be difficult to attribute to a particular treatment component. The recorded enrollment was 6, and the safety groups included 5 participants at risk in the radiation-therapy group and 1 in the surgery group. Such limited group sizes also restrict the information available from descriptive counts.
The endpoint description allows response assessment from PET activity, radiologic measurements, and direct measurements, using the largest percentage change and a unidimensional approach similar to RECIST 1.1. The record does not report how measurement-source differences were resolved, assessor procedures, or detailed analysis methods. It also does not describe missing-data methods, analysis populations, multiplicity handling, or sensitivity analyses. These items are not reported in the registry record, so it is not possible to judge how they might have affected an analysis.
The registry marks the study terminated, but the record does not provide additional details about the termination beyond the documented amendment concerning the biopsy procedure. No further reason should be inferred. The planning assumptions are described only as an illustration and do not substitute for a reported trial-specific sample-size justification or analysis plan.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Identification of Gene Expression Signature for Panitumumab Sensitivity in Untreated Locally Advanced SCCHN — NCT01305772.
- Registry record last updated 2014-08-29; status last verified 2014-08.
- Results first posted 2014-08-29.
- 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.
Continue through the Clinical Biostats statistical pathway
Use this trial's endpoint as a starting point for deeper study of effect measures, confidence intervals, and sample-size planning.
18. Record Summary
This phase 2 study examined panitumumab with radiation-based treatment in untreated locally advanced squamous cell cancer of the head and neck. It used a nonrandomized, unmasked, parallel-group design and is recorded as terminated. The two pathways were surgery followed by radiation therapy with panitumumab, and radiation therapy with panitumumab without surgery.
The primary objective was to identify a gene-expression signature associated with response, assessed through tumor and lymph-node change from baseline to 2 years. The registry reports no primary-outcome results because only 2 of the 6 subjects had tissue collected after the first dose; the biopsy procedure was removed because of potential participant risk. The record also lists 9-month progression-free survival and 9-month overall survival as secondary outcomes, without reported results.
Adverse-event counts are descriptive, and the groups are not randomized comparators. The registry does not report analyses, detailed statistical methods, or death counts. The available record therefore describes the intended research question and its limitations but does not quantify treatment response or establish a predictive biomarker.