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 Image-Guided Stereotactic Biopsy of High Grade Gliomas (NCT00979810), a na na study. The primary outcome is Invest Relation Btw Voxel-based Determ of Prolif Rate & Obser MR Imaging Featu (i.e., Ktrans or Microvas Permeabil; fBV, Tiss Fract Blood Vol), as Well With Spatially Reg Histolog Meas of Tum Cell Prolif (Ki67) & Microvas Density (CD31) at Corres Locat..
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00979810 |
| Phase | NA |
| Condition | Brain Cancer, Glioma |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 11 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Memorial Sloan Kettering Cancer Center |
| Results posted | Yes |
2. Clinical Question
Population
The study was intended to collect preliminary data on patients with untreated high-grade glioma who were scheduled for surgical resection. The registry describes an intended group of 15 patients and records enrollment of 11. The conditions listed are Brain Cancer and Glioma.
Intervention
The intervention was an 18F-FLT PET scan. The study description says the scan was intended to identify variation in tumor growth or proliferation and to relate imaging findings to tumor biology measured in sampled tissue.
Comparator
There was no separate control group or randomized comparison. The registry classifies the study as single-group and lists allocation as NA. Within-tumor areas and imaging or tissue measures were to be related, but these are not separate treatment arms.
Primary question
The primary question was whether voxel-based estimates of proliferation rate were related to MRI features, including Ktrans or microvascular permeability and fBV, and to spatially matched histology measures of tumor-cell proliferation (Ki67) and microvascular density (CD31). The registry states that data were not collected for this primary measure.
This is a question about correspondence between measurements, not a comparison of clinical outcomes between treatments. A voxel-based estimate describes an imaging-derived value associated with a particular tumor location. The planned spatial comparison matters because tissue samples and imaging measures are most informative when they refer to corresponding regions. The registry’s description also frames the work as an investigation of whether imaging could characterize differences in tumor growth within a tumor.
That scientific aim should be distinguished from evidence that the imaging measures correspond to tissue biology. The record states that primary data were not collected, and it does not report estimates of association, uncertainty intervals, or a test of the primary question. Consequently, the study record describes the intended question but does not establish an answer to it.
3. Trial Design
The registry describes a completed, single-group pilot study of 18F-FLT PET imaging in high-grade glioma. The intervention is listed as an 18F-FLT PET Scan. The brief description says the study involved obtaining one FLT PET scan and aimed to relate imaging findings to tumor biology measured in sampled tumor tissue. The arm description characterizes the project as a pilot intended to collect preliminary data on 15 patients with untreated high-grade glioma scheduled for surgical resection. The enrollment recorded in the registry is 11.
The record gives a start date of 2009-09-16, a primary completion date of 2020-02-24, and a status of COMPLETED. These registry fields describe the study record and its administrative status; they do not establish that the planned primary measurements were completed. In fact, the primary outcome population field says “Data were not collected.” The record lists phase and allocation as NA and masking as NONE. It does not describe a randomized or masked treatment comparison.
With one group and no control arm, the design is not suited to a like-for-like comparison of alternative treatments. Its stated focus is measurement: comparing imaging-derived estimates with MRI features and histology measurements at corresponding locations. The secondary aims further concern imaging approaches, uptake measures, tissue assays, and gene-expression patterns. The registry includes three secondary outcome descriptions, but it does not report results for them.
The registry does not report a statistical analysis plan, a sample-size justification, or an explanation for the relationship between the intended enrollment and the enrollment recorded. It also does not report whether all planned imaging, surgery, or tissue procedures were completed. The completed status should therefore be read alongside the explicit statement that primary data were not collected, rather than as evidence that the primary scientific question was answered.
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
| Stage | 18F-FLT PET Scan |
|---|---|
| STARTED | 11 |
| COMPLETED | 11 |
| NOT COMPLETED | 0 |
Analysis population for the primary outcome, as defined in the registry: Data were not collected
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 | 18F-FLT PET Scan |
|---|---|---|
| Participants analysed | 11 | |
| Age, Continuous | years | 57 (41 to 75) |
| Sex: Female, Male: Female | Participants | 4 |
| Sex: Female, Male: Male | Participants | 7 |
| Ethnicity (NIH/OMB): Hispanic or Latino | Participants | 0 |
| Ethnicity (NIH/OMB): Not Hispanic or Latino | Participants | 11 |
| Ethnicity (NIH/OMB): Unknown or Not Reported | Participants | 0 |
| 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 | 0 |
| Race (NIH/OMB): White | Participants | 11 |
| Race (NIH/OMB): More than one race | Participants | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 0 |
| Region of Enrollment: United States | Participants | 11 |
6. Primary Endpoint
The registry lists the primary outcome as Invest Relation Btw Voxel-based Determ of Prolif Rate & Obser MR Imaging Featu (i.e., Ktrans or Microvas Permeabil; fBV, Tiss Fract Blood Vol), as Well With Spatially Reg Histolog Meas of Tum Cell Prolif (Ki67) & Microvas Density (CD31) at Corres Locat., measured over 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 measure concerns the relationship between voxel-based estimates of tumor proliferation and other measurements from imaging and tissue. The listed imaging features include Ktrans or microvascular permeability and fBV, described in the registry as tissue fractional blood volume. The planned tissue measures are Ki67 for tumor-cell proliferation and CD31 for microvascular density, assessed at corresponding locations.
These measures address related but distinct aspects of tumor biology. In general, an imaging-derived estimate is useful to investigate when it can be compared with a biological measure that reflects the feature it is intended to characterize. A spatially matched comparison is important because a tumor may contain regions with differing characteristics; matching locations helps make the comparison interpretable. This is a general explanation of the measurement rationale, not a reported finding from this study.
The registry describes association as the primary aim, not a treatment effect or a patient outcome. To evaluate that aim, the study would need collected paired imaging and tissue data and a reported analysis of how the measurements relate. The record does not give a unit, parameter, dispersion measure, result, or analysis for the primary outcome. Most importantly, the primary population field states “Data were not collected.” Thus, the endpoint identifies what the investigators intended to examine, but the registry record does not provide evidence about the strength or direction of any relationship.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The central interpretive fact is that the registry lists a specific primary measurement question but states that data were not collected for it. The record therefore does not report a primary estimate of association between voxel-based proliferation measures, MRI features, and spatially matched histology. There is no reported direction or magnitude of association, no confidence interval, and no primary-outcome test result. The study’s stated aim should not be mistaken for a finding.
The registry records enrollment of 11 and describes an intended pilot group of 15 patients. Those figures describe enrollment and the intended preliminary-data group; they do not show how many contributed usable paired imaging and tissue measurements. The record does not report a primary analysis population or the availability of paired observations. Nor does it state why the planned primary data were not collected. That information is not reported in the registry record.
The study is single-group, and its primary question concerns agreement or association among measurements rather than a contrast between treatments. There is therefore no randomized control group from which to estimate a comparative intervention effect. A single-group measurement study can be informative if the relevant measurements are collected and analyzed, but the record does not report those primary data or analyses. The completion status does not change this limitation.
The listed secondary aims provide context about the broader measurement program. They concern comparing voxel-based and ROI-based parameter estimates, assessing static uptake versus parametric imaging as a non-invasive marker, and examining gene-expression differences across areas with different proliferative activity. These are proposed or registered aims, not results. The record gives no secondary outcome results and lists zero analyses.
The adverse-event fields are separate from the imaging endpoint. For the 18F-FLT PET Scan group, the registry records 11 at risk for serious adverse events and 0 affected; it also records 11 at risk for other adverse events and 0 affected. The deaths field lists 11. These counts alone do not provide event timing, cause, relationship to the scan, or clinical context. They cannot establish that the scan caused deaths, nor do they explain the relationship between deaths and the absence of collected primary data.
Overall, the registry documents a research question and a completed single-group study record, but not an evaluable primary result. The appropriate statistical reading is therefore about the limits of the available evidence: no primary association estimate is reported, and the record does not support a conclusion about the imaging measures’ performance or their relationship to tumor biology.
9. Statistical Methods Explained
What does an association analysis ask?
In general, an association analysis asks whether two measured quantities vary together across the observations in a study. For this study, the intended quantities included voxel-based proliferation estimates, MRI features, and tissue measurements. An association is not the same as agreement: two measures may move together while differing systematically in scale, and a strong association does not by itself show that one measure can replace another. The registry does not report which specific association statistic or agreement method was planned.
Interpretation also depends on what constitutes an observation. The primary description refers to voxel-based estimates and spatially corresponding measurements. Multiple locations from one person are not automatically equivalent to measurements from different people, because observations within a person may be related. In general, an analysis of clustered measurements needs to account for that dependence if it is present. The registry does not report the unit of analysis, the number of sampled locations, or a method for handling repeated or spatially related measurements.
Why do confidence intervals matter?
In general, a confidence interval expresses the uncertainty around an estimated quantity under the assumptions of the analysis. A narrow interval indicates greater precision than a wide interval, while an interval spanning a broad range of plausible values leaves more uncertainty. A confidence interval is not a guarantee about an individual observation, and its interpretation depends on the design and statistical method. No confidence interval for the primary outcome is reported in the registry record, so precision cannot be assessed.
What can a p-value establish?
In general, a p-value summarizes how incompatible the observed data are with a specified null model, assuming that model and the analysis assumptions hold. It does not quantify the size or practical importance of an association, and it does not establish that a proposed biological explanation is true. A p-value also cannot substitute for an estimate and its uncertainty. The registry lists zero analyses and reports no primary p-value or test result. The statistical test, if any, is not reported in the registry record.
Why might measurement properties matter?
Imaging and tissue measures can differ in scale, variability, and the biological feature they capture. In general, measurement error can weaken or distort observed relationships, while differences in how locations are matched can complicate interpretation. An imaging signal may be a candidate marker without being a direct measurement of the tissue process of interest. Comparing voxel-based estimates with ROI-based estimates, static uptake, parametric images, and histology addresses different measurement questions; one kind of comparison does not automatically answer the others. The registry lists these as aims but does not report the measurement procedures in enough detail to assess their performance.
Over-dispersion is a general issue when observed variability is greater than a statistical model expects. If a model assumes less variation than the data contain, uncertainty estimates may be too small and tests may be misleading. The registry does not report a primary statistical model, a variance assumption, or any assessment of over-dispersion. This is a general consideration, not a claim that over-dispersion occurred in this study.
How should the design shape the analysis?
The study is listed as single-group, with no randomized comparison. That design fits the stated goal of relating measures within a group, but it does not provide a treatment-control contrast. In general, an association analysis in a single group can describe how variables co-vary in the analyzed observations; it cannot by itself establish that an imaging feature causes a tissue feature or that the imaging approach changes a clinical outcome. No causal or treatment-effect interpretation is reported for this primary measure.
The registry includes generic planning assumptions for sample-size illustrations: two-sided significance level 0.05, equal allocation between two arms, a normal approximation, and an effect defined as a stated fraction of an observed effect. Those assumptions describe planning illustrations, not the design of this single-group study. The illustrations are not the trial’s own design or evidence about observed power. The registry does not report the effect estimate used for such illustrations or a study-specific sample-size justification. Since the primary outcome population is marked as data not collected, the record also does not provide a primary observed effect to interpret.
More broadly, planning calculations depend on assumptions about the outcome, variability, effect size, allocation, and analysis. If those assumptions do not match the actual design or outcome, the resulting illustration may not be applicable. A planning illustration is not evidence that a study had adequate precision, and it does not replace a reported estimate with uncertainty. Here, the two-arm assumption differs from the listed single-group model, so it should not be read as describing the enrolled study.
The registry does not report an analysis population, handling of missing measurements, covariate adjustment, model diagnostics, or a prespecified statistical plan. It would not be appropriate to infer any of these from the outcome wording. Because the primary data are explicitly described as not collected, the main statistical conclusion is not that a particular analysis failed to detect an association; rather, no primary analysis result is reported.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists a primary outcome and three secondary outcome descriptions. Together, these cover several related but distinct questions about imaging-derived proliferation measures, MRI features, histology, static uptake, parametric images, and gene-expression patterns. When multiple outcomes or analyses are examined, general statistical practice recognizes a multiplicity issue: the chance of at least one apparently notable result can increase when many tests are conducted. Methods such as prespecifying a primary analysis or adjusting for multiple testing can address particular multiplicity concerns, but the appropriate approach depends on the analysis goals.
The registry does not report a multiplicity strategy, a hierarchy of secondary hypotheses, or a statistical analysis plan. It also lists zero analyses. Therefore, the record does not permit an assessment of whether any adjustment was used or whether the registered outcomes were analyzed. No claim about the presence or absence of selective reporting can be established from these fields alone.
Missing-data handling and analysis populations are also not reported. The primary outcome population is explicitly described as “Data were not collected.” The registry does not explain whether this means no measurements were obtained, whether some components were unavailable, or why the primary data were not collected. It does not provide counts of participants or locations with complete imaging and tissue measurements, nor does it describe imputation, exclusions, or sensitivity analyses. These details are not reported in the registry record.
In general, missingness can affect both the amount of information available and the interpretation of an analysis, especially if the availability of measurements is related to participant or tumor characteristics. No such pattern can be assessed from this record. The enrollment field and adverse-event counts do not define the primary analysis population. The stated absence of primary data means there is no reported primary estimate to interpret under any missing-data assumption.
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 |
|---|---|---|---|
| 18F-FLT PET Scan | 0 | 11 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| 18F-FLT PET Scan | 11 of 11 |
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 |
|---|---|
| 18F-FLT PET Scan | 0 of 11 |
The registry records the 18F-FLT PET Scan group as having 11 participants at risk for serious adverse events and 0 participants affected by serious adverse events. It also records 11 at risk for other adverse events and 0 affected by other adverse events. These are counts, not rates, and the record does not provide event descriptions or a time period for interpreting the counts.
The deaths field lists 11. The registry does not report when these deaths occurred, their causes, whether they were considered related to the scan, or the circumstances in which they were recorded. The death count should therefore be reported as a registry count without attributing it to the imaging intervention. The adverse-event fields alone do not explain the relationship between the deaths and the zero counts for affected participants.
In general, safety counts require context about definitions, follow-up, attribution, and completeness of reporting. A count of zero for a category does not establish that no event of any kind occurred; it indicates that no affected participants are recorded in that particular field. The record does not report further safety details that would allow a fuller assessment.
12. What the Result Does, and Does Not, Mean
The registry establishes the study’s intended scientific question: whether imaging-based measures of proliferation relate to MRI features and tissue measurements in high-grade glioma. It also documents a single-group design, an 18F-FLT PET scan intervention, enrollment of 11, and a completed status. These details describe the registered study and its aims.
The record does not establish that voxel-based imaging estimates correspond to histology, that static uptake is or is not an adequate marker, or that one imaging approach is preferable to another. Those are among the questions in the primary and secondary aims, but no outcome results are reported. The primary outcome population is explicitly marked “Data were not collected,” and the record lists zero analyses. There is consequently no reported effect estimate or uncertainty measure from which to draw a statistical conclusion about the primary question.
This absence of a result is different from a finding of no association. A null finding would require collected data and an analysis that estimated the relationship with an appropriate level of uncertainty. The registry does not report such an analysis. It is also not possible to conclude that the intended imaging approach succeeded or failed on the basis of the aims alone.
The record does not describe a randomized comparison or a separate control group, so it does not support a comparative treatment-effect conclusion. Nor does the record report clinical outcomes that would establish a change in patient outcome. The study description says that the information may be useful in future research, but that purpose is not evidence of a clinical benefit in this study.
The safety counts require similarly limited interpretation. The registry records zero affected participants in the serious and other adverse-event fields and lists 11 deaths, but it does not report timing, cause, or attribution. Neither the counts nor the study’s completed status resolve those missing details. The statistically defensible meaning is therefore narrow: the registry records the planned measurement questions and administrative study information, while providing no collected primary outcome data or analysis with which to answer the central scientific question.
13. Why This Trial Matters Statistically
This study matters statistically because it illustrates the distinction between a registered measurement question and an analyzable result. The aims are specific: compare voxel-based estimates with imaging features and spatially corresponding histology, and explore related imaging and molecular questions. Such questions can be important in methods research, where the key issue is whether measurements characterize the biological feature they are intended to represent. But specificity of the aim does not supply evidence in the absence of collected outcome data.
The record also highlights why the design and the proposed analysis need to align. The study is listed as single-group, while the generic planning assumptions describe equal allocation between two arms. Those planning assumptions are not a description of the actual design. Distinguishing a calculation used for planning from an analysis of observed study data helps prevent a planning illustration from being mistaken for a result or a guarantee of precision.
Spatial matching is another useful statistical consideration. In general, measurements taken from corresponding tumor locations can address a more targeted question than an unpaired comparison, but location-level observations may be related within the same person. An analysis needs to define its observational unit and account for dependence where appropriate. The registry does not report those analytic details, and the primary-data field states that data were not collected.
Finally, the record underscores the importance of interpreting completion status, enrollment, outcomes, and safety fields as distinct pieces of information. A completed registry status does not itself demonstrate that the primary endpoint was measured or analyzed. Enrollment does not tell readers how many paired measurements were available. Safety counts do not answer the imaging-biology question. Keeping these distinctions clear prevents the study’s rationale from being confused with evidence about measurement performance or clinical effects.
14. Limitations
- The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
- Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.
The most direct limitation is that the registry states “Data were not collected” for the primary outcome population. No primary association estimate, confidence interval, or analysis result is reported, so the central measurement question cannot be evaluated from the registry record.
The study is listed as single-group, with allocation recorded as NA and masking as NONE. It has no separate control group or randomized treatment comparison. This limits the kinds of conclusions the design can support; in particular, the registered question is about measurement relationships, not a comparative treatment effect. The record does not report a statistical analysis plan or explain how the primary association was to be estimated.
The arm description states that the pilot was intended to collect preliminary data on 15 patients, while the enrollment field records 11. The registry does not explain this difference or state how many participants had usable imaging and corresponding tissue measurements. The number of locations assessed, the unit of analysis, and the handling of measurements that may be related within a participant are not reported.
The record gives limited detail about outcome measurement and analysis. It does not specify a primary statistical parameter, unit, dispersion measure, model, or approach to missing data. It lists three secondary aims but no secondary results, and it does not report a multiplicity strategy. The generic planning assumptions use a two-arm framework even though the study is listed as single-group; they should not be interpreted as the study’s own design or as evidence of precision.
Safety interpretation is also limited by the absence of event timing, cause, and attribution. The registry lists zero affected participants in the serious and other adverse-event fields and 11 deaths, but does not provide context to explain those counts. These limitations concern what is documented in the registry record; they do not establish why data or details are absent.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Image-Guided Stereotactic Biopsy of High Grade Gliomas — NCT00979810.
- Registry record last updated 2020-12-17; status last verified 2020-02.
- Results first posted 2020-12-17.
- 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
NCT00979810 is a completed, single-group pilot study titled “Image-Guided Stereotactic Biopsy of High Grade Gliomas.” The registered intervention is an 18F-FLT PET scan. The study aimed to relate voxel-based estimates of tumor proliferation to MRI features and spatially matched tissue measures, including Ki67 and CD31. Its secondary aims concern alternative imaging estimates, uptake measures, parametric images, histology, and gene expression.
The record gives enrollment of 11 and describes an intended preliminary-data group of 15 patients with untreated high-grade glioma scheduled for surgical resection. It lists a start date of 2009-09-16, a primary completion date of 2020-02-24, and status COMPLETED. The primary outcome population is marked “Data were not collected,” and zero analyses are listed. No primary association result is reported. The safety fields record 0 affected participants for serious adverse events, 0 for other adverse events, and 11 deaths; timing and attribution are not reported.