A Study of Radiation Therapy and Paclitaxel and Carboplatin in Patients With Uterine Papillary Serous Carcinoma: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for A Study of Radiation Therapy and Paclitaxel and Carboplatin in Patients With Uterine Papillary Serous Carcinoma (NCT00231868), a na phase 2 study. The primary outcome is To Evaluate the Toxicity and Tolerability of Pelvic Radiation "Sandwiched" Between Cycles of Paclitaxel/Carboplatin Chemotherapy in Patients With UPSC.

2. Clinical Question

The clinical question is therefore about the experience of participants receiving the combined treatment, rather than a comparative estimate of benefit or harm versus another regimen. The record describes the intended evaluation as including survival analysis for early-stage and late-stage UPSC. It does not report stage-specific results, survival estimates, or a numerical toxicity summary for the trial cohort. The single-group design can describe outcomes among participants treated in this study, but it cannot by itself separate treatment effects from the natural course of disease or other influences on outcomes.

3. Trial Design

NCT00231868 is listed as a completed phase 2 study sponsored by Montefiore Medical Center. The registry record describes a single-group study, with no masking and allocation listed as not applicable. Enrollment is reported as 81. The intervention is a sequence of paclitaxel and carboplatin chemotherapy with pelvic radiation between chemotherapy cycles. The record describes the radiation as “sandwiched” between three cycles of chemotherapy before and after radiation.

This design is suited to describing the experience of a group treated with the planned regimen. It does not create a randomized contrast with another treatment, and the record does not identify a separate control arm. Consequently, outcomes in the treated group cannot be interpreted as a direct estimate of the difference that would have occurred under an alternative regimen. The registry record does not report a protocol-level explanation of why a single-group design was selected or how the enrollment target was justified.

The study's stated primary objective concerns toxicity and tolerability. The outcome description, however, refers to Kaplan-Meier analysis of PFS and OS, with results to be considered for early-stage and late-stage patients. The primary measure is described as a mean in months with standard error, while the accompanying description identifies time-to-event outcomes. This leaves uncertainty about the precise endpoint definition and the statistic intended for reporting. That ambiguity matters because a mean and a Kaplan-Meier survival estimate summarize outcomes differently.

The registry record reports a timeframe of up to 7 years for the primary outcome. It does not provide participant flow, treatment completion, follow-up completeness, or the number included in each outcome analysis. The 81 enrolled participants and the 72 participants listed as at risk for the serious-adverse-event summary are distinct reported counts; the reason for that difference is not reported in the registry record.

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

Analysis population for the primary outcome, as defined in the registry: Kaplan-Meier survival analysis of Progression Free Survival (PFS) and Overall Survival (OS).

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: We considered 72 patients as baseline participants because they are the ones who completed the first three cycles of chemotherapy followed by at least partial RT. Of the 72 patients, 65 of them completed all prescribed regimen of treatment. This was the reason for the discrepancy.

6. Primary Endpoint

The registry lists the primary outcome as To Evaluate the Toxicity and Tolerability of Pelvic Radiation "Sandwiched" Between Cycles of Paclitaxel/Carboplatin Chemotherapy in Patients With UPSC, measured over Up to 7 years.

The stated primary objective is to evaluate toxicity and tolerability of pelvic radiation given between cycles of paclitaxel and carboplatin in patients with UPSC. The outcome description also names PFS and OS and describes Kaplan-Meier survival analysis. PFS concerns the time until disease progression or death, while OS concerns the time until death. These are time-to-event outcomes: they account for both whether an event occurred and the time at which it occurred, while participants without an event at their last observation may contribute follow-up information without being counted as having had the event.

Time-to-event measures are often used when the timing of disease progression or death is clinically relevant and follow-up lengths can differ. Kaplan-Meier methods can estimate the probability of remaining event-free over time while accommodating right-censored observations, subject to assumptions about censoring. This is a general explanation of the method; the registry record does not report the censoring details or analysis choices used in this study.

The endpoint description does not fully align with the stated primary objective. It labels the result as a mean in months with standard error, while describing Kaplan-Meier analyses of PFS and OS. The record does not explain whether the mean refers to survival time, a different measure, or a reporting convention. Nor does it give a numerical estimate, standard error, confidence interval, event count for PFS, or survival result for OS. Thus, the endpoint's intended clinical focus can be identified, but its exact operational definition and observed estimate are not reported in the registry record.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry describes a single-group phase 2 study and identifies Kaplan-Meier analysis for PFS and OS. It does not post any analyses. The methods below explain the statistical ideas named or relevant to the stated outcomes in general; they do not establish which detailed procedures were actually used.

What Kaplan-Meier analysis represents

Kaplan-Meier analysis estimates the probability of remaining free of a defined event over follow-up time. For PFS, the event definition would need to specify how progression and death are counted; for OS, the event is death. The registry record names these outcomes but does not report their complete operational definitions, event-adjudication procedures, or the date from which follow-up time was measured.

A key feature of time-to-event data is censoring. A participant may have no recorded event by the end of available follow-up, or may leave observation earlier. Such a participant can contribute information up to the last known event-free time without being treated as though an event occurred then. Kaplan-Meier estimation relies on assumptions about censoring; for example, censoring should not be systematically related to the unobserved event time in a way that biases the estimate. The registry record does not report censoring counts, reasons, or an assessment of these assumptions.

Mean, standard error, and the endpoint description

The primary outcome is labeled as a mean measured in months with standard error, while its description specifies Kaplan-Meier survival analysis. A mean is a measure of the average, and a standard error describes the estimated sampling uncertainty around a statistic. For time-to-event data with censored observations, a simple arithmetic mean of observed follow-up times does not generally estimate mean survival time. There are methods for estimating mean survival time from a survival curve, but the record does not identify such a method or state that it was used. It does not explain whether the listed mean refers to PFS, OS, or another quantity.

A confidence interval is a range calculated by a statistical procedure to express uncertainty around an estimate. It is not a guarantee that the true value lies in that particular interval. No confidence interval is reported for the outcomes in the registry record, so their precision cannot be assessed from posted survival estimates. The stated standard error alone is also not accompanied by an estimate.

Single-group interpretation

With one treatment group and no randomized comparator, the analysis can describe outcomes among participants in that group. It cannot directly estimate a treatment contrast against a control group. Comparisons between the early-stage and late-stage groups, if conducted, would be comparisons within the study rather than randomized treatment comparisons. The registry record does not report such estimates or tests. Differences between stage groups could reflect underlying differences between participants as well as chance; statistical adjustment or causal interpretation cannot be assumed.

Planning assumptions are not trial results

A planning illustration associated with the statistical material uses a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. For time-to-event planning, it describes the total number of events using the Schoenfeld approach; other planning quantities are expressed as participants per arm. These are assumptions for hypothetical planning illustrations, not evidence that this single-group study used a two-arm design or those assumptions in its protocol. No calculated sample-size illustration values are reported in the registry record, and no protocol sample-size justification is reported there.

Planning sample sizes answer a different question from observed results. They describe how many participants or events a hypothetical design might require under stated assumptions. They do not show whether a study found an effect, and they are not observed power. The registry record does not report the effect size or other protocol assumptions used to choose enrollment of 81.

Over-dispersion and count outcomes

For general context, over-dispersion occurs when count data vary more than expected under a model such as a Poisson model. Ignoring it can make uncertainty appear too small and statistical evidence appear stronger than warranted. No count-model analysis, over-dispersion assessment, or event-count outcome model is reported in the registry record, so this concept should not be taken as a description of the study's analysis.

10. Multiplicity, Missing Data and Analysis Populations

The registry record does not report a statistical plan for handling multiplicity. It identifies PFS and OS in the outcome description and distinguishes early-stage (stage 1 & 2) from late-stage (stage 3 & 4) UPSC, but it does not state which outcome was primary for inference, whether stage-specific analyses were planned, or whether any adjustment for multiple comparisons was intended. When several outcomes or subgroup comparisons are examined, the chance of at least one apparently notable result can increase. A prespecified analysis hierarchy or adjustment can help address that issue, but the record does not say whether either was used.

Missing-data methods are also not reported. For survival analysis, incomplete follow-up is commonly represented through censoring, but the record does not provide the number censored, the reasons for censoring, the completeness of follow-up, or the assumptions used. It does not state how missing stage information, outcome assessments, or other participant data were handled.

The registry lists enrollment of 81 and reports 72 participants at risk in the serious-adverse-event summary. It does not explain which participants are included in that safety denominator or why it differs from enrollment. Nor does it report the number included in PFS or OS analyses. Analysis populations such as intention-to-treat, treated, or evaluable participants are not defined in the registry record.

The record lists zero analyses. This means the registry entry does not contain posted analysis results to evaluate; it does not establish that no analyses were conducted outside the registry. No interim-analysis plan, stopping rule, or adjustment for interim monitoring is reported in the registry record. Without these details, the extent to which analysis choices were prespecified and how incomplete observations affected estimates cannot be determined.

11. Safety Results

The registry reports serious adverse events as affected participants divided by participants at risk.

Deaths

Other (non-serious) adverse events

Participants with at least one non-serious event at or above the registry's 0% reporting threshold.

The serious-adverse-event summary lists 72 participants at risk and 0 affected in the group receiving carboplatin, paclitaxel, and pelvic radiation. It separately lists 16 deaths. These entries should not be combined into a claim about treatment-related mortality: the registry record does not state whether the deaths were caused by treatment, occurred during treatment, or were classified as serious adverse events. Causes and timing are not reported.

The zero affected count applies to the serious-adverse-event summary as posted. It does not establish that participants experienced no adverse effects of any kind. The registry record does not provide a detailed account of non-serious adverse events for the trial cohort, and its serious-event terms list is empty. The brief summary describes toxicities in an earlier retrospective review of 16 patients; those observations are not the safety results for this prospective study.

The listed safety denominator of 72 differs from the enrollment count of 81. The reason is not reported in the registry record, so the denominator should not be assumed to represent all enrolled participants or a particular treatment-exposure population. Without participant-level follow-up, event definitions, attribution, and the reason for the denominator, the safety summary is limited to the counts as recorded.

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

The registry record documents a completed phase 2, single-group study of a chemotherapy and pelvic-radiation sequence in patients with UPSC. It identifies toxicity and tolerability as the primary objective and names PFS and OS in the outcome description. The serious-adverse-event summary reports 0 affected among 72 at risk and separately records 16 deaths. Those entries describe what is posted, but they do not provide enough detail to determine the cause, timing, treatment relationship, or completeness of safety follow-up.

The record does not report numerical PFS or OS estimates, their uncertainty, or stage-specific results. It therefore cannot establish how long participants remained free of progression or how survival varied over time. The endpoint description also leaves uncertainty about whether the intended primary summary was a mean in months or a Kaplan-Meier survival estimate. No interpretation of the size or precision of an efficacy result is possible without an estimate and its uncertainty.

Because the study has one group and no reported comparator, it does not provide a randomized estimate of how outcomes would differ under another treatment. Outcomes observed in a single group can reflect disease characteristics, participant selection, other care, follow-up patterns, and chance as well as the regimen. The registry record does not report an adjusted comparison that could address those issues.

The earlier retrospective review mentioned in the brief summary is distinct from this prospective study. Its observations should not be attributed to the 81 enrolled participants. Likewise, planning assumptions used in statistical illustrations are not evidence of an observed treatment effect and do not establish the trial's original design rationale.

Overall, the record supports a description of the study's design, intervention, stated objectives, and limited posted safety counts. It does not support a quantified conclusion about survival outcomes, a comparison with another treatment, or a complete characterization of toxicity. Important details about endpoint definitions, follow-up, analysis populations, and missing data are not reported in the registry record.

13. Why This Trial Matters Statistically

This study is statistically notable because its stated primary objective and its outcome description do not align cleanly. The objective emphasizes toxicity and tolerability, while the outcome description identifies PFS and OS and names Kaplan-Meier analysis. At the same time, the primary measure is labeled as a mean in months with standard error. These summaries answer different statistical questions, so clear endpoint definitions are essential for readers to know what was measured and how to interpret the result.

The single-group design also sets an important boundary on interpretation. A study can describe outcomes in participants receiving a regimen, but without a comparator it cannot directly estimate how those outcomes differ from an alternative. This distinction is especially important when the brief summary refers to preliminary findings from a separate retrospective review. Keeping prior observations separate from prospective trial results avoids attributing evidence to the wrong group of participants.

The safety counts illustrate why denominators and event definitions matter. Enrollment is listed as 81, while the serious-adverse-event summary lists 72 at risk. The reason for the difference is not reported. The count of 16 deaths is also separate from the count of participants affected by serious adverse events, and no cause or treatment attribution is given. Each number therefore requires its own definition and context rather than a broad interpretation.

Finally, the absence of posted analyses means readers cannot evaluate the estimated survival experience or its precision. A named method does not substitute for results, and a stated follow-up timeframe does not reveal how complete follow-up was. The record leaves unanswered questions about analysis populations, censoring, missingness, and multiplicity. These are not merely reporting details: they determine how reliably an estimate can be understood and how far it can be generalized.

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 offers limited information for evaluating the trial's results. Although the study is marked completed and enrollment is reported as 81, it posts no analyses. Numerical estimates for PFS and OS, confidence intervals, event counts, and stage-specific findings are not reported in the registry record. As a result, readers cannot assess outcome magnitude or precision.

The endpoint information is internally unclear. The primary objective concerns toxicity and tolerability, whereas the outcome description specifies PFS and OS. The measure is listed as a mean in months with standard error, but the description refers to Kaplan-Meier survival analysis. The record does not resolve this difference or define the analysis time origin and event criteria.

There is no separate comparison group. This prevents direct assessment of outcomes relative to another regimen and limits causal interpretation. The record also does not report participant flow, treatment completion, detailed follow-up, analysis populations, missing-data handling, or censoring information. The safety summary's 72 participants at risk differs from enrollment of 81, with no explanation. The 16 deaths have no reported cause, timing, or treatment attribution.

The registry record does not report a sample-size justification, interim-analysis plan, multiplicity strategy, or detailed statistical analysis plan. Nor does it state how the early-stage and late-stage groups were defined beyond the stage labels in the outcome description or whether separate comparisons were planned. The brief summary's retrospective findings concern 16 patients from an earlier review, not the prospective trial cohort, and cannot fill the gaps in the trial's posted results.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: A Study of Radiation Therapy and Paclitaxel and Carboplatin in Patients With Uterine Papillary Serous Carcinoma — NCT00231868.
• Registry record last updated 2020-08-12; status last verified 2020-08.
• Results first posted 2020-08-12.
• 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

NCT00231868 is a completed phase 2, single-group study sponsored by Montefiore Medical Center, with enrollment reported as 81. It evaluates paclitaxel and carboplatin chemotherapy combined with pelvic radiation, described as radiation “sandwiched” between chemotherapy cycles. The primary objective concerns toxicity and tolerability; the outcome description also names PFS and OS and refers to Kaplan-Meier analysis over a timeframe of up to 7 years.

The serious-adverse-event summary lists 72 participants at risk, 0 affected, and 16 deaths. The registry record does not explain the difference between the enrollment and safety counts or report causes and treatment attribution for deaths. It lists zero analyses and does not report numerical survival results, endpoint estimates, confidence intervals, or stage-specific outcome findings. The record also does not explain the mismatch between the stated toxicity objective and the survival-focused outcome description, or between the mean-with-standard-error label and the Kaplan-Meier description.