This page provides an independent statistical analysis and educational interpretation of publicly reported results. ClinicalTrials.gov provides the official trial registry record.
1. Trial at a Glance
CARMENA was a phase 3 randomized parallel-group trial evaluating the importance of nephrectomy in metastatic renal cell carcinoma.
| Feature | CARMENA |
|---|---|
| Condition | Metastatic Renal Cell Carcinoma |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | None |
| Primary purpose | Treatment |
| Lead sponsor | Assistance Publique - Hôpitaux de Paris |
| Interventions | Nephrectomy (procedure); Sunitinib alone (other) |
2. Clinical Question
Population
Patients with metastatic renal cell carcinoma.
Intervention
Nephrectomy.
Comparator
Sunitinib alone.
Primary question
The trial assessed the importance of nephrectomy using overall survival as the primary endpoint.
3. Trial Design
Randomization
The trial used randomized allocation with a parallel design.
Enrollment
A total of 452 participants were enrolled.
Study arms
The trial included 2 arms comparing nephrectomy and sunitinib alone.
Study period
Start date: 2009-09-09. Primary completion date: 2018-10-22.
4. Endpoints
| Endpoint | Definition | Time frame |
|---|---|---|
| Overall survival | The primary endpoint is overall survival. | Starting at 4 months |
5. Planned Analysis
The ClinicalTrials.gov record identifies overall survival as the primary endpoint. No statistical analyses are posted in the registry.
For randomized oncology trials with overall survival as a time-to-event endpoint, statistical evaluation commonly uses methods designed for censored survival data. These approaches generally estimate survival over time, compare treatment groups, and quantify uncertainty around treatment differences.
Overall survival analysis concepts
Overall survival measures the time from a defined starting point until death from any cause. Because some participants may still be alive at analysis, survival methods account for right censoring rather than treating those observations as complete failures or complete successes.
6. Statistical Methodology
Randomization
Randomization creates comparable treatment groups on average and allows differences in outcomes between groups to be interpreted as arising from the assigned interventions rather than systematic baseline differences.
Time-to-event analysis
Overall survival is a time-to-event endpoint. Methods for this endpoint must account for patients who have not experienced the event by the end of follow-up.
Hazard ratios
A hazard ratio is commonly used in survival analysis to summarize the relative rate of an event between groups over time. It is a relative measure and does not directly represent the difference in the proportion of patients surviving at a specific time point.
7. Statistical Methods Explained
Why is overall survival analyzed as a time-to-event endpoint?
Death occurs at different times for different patients, and some patients may remain alive when analysis occurs. Survival methods preserve information from these incomplete observations.
Why does randomization matter?
Randomization helps balance known and unknown factors between treatment groups, supporting an unbiased comparison of outcomes.
What does a hazard ratio describe?
A hazard ratio compares estimated event rates over time. It does not mean that every individual patient experiences the same proportional change.
Why are confidence intervals important?
Confidence intervals describe uncertainty around an estimate and provide information about precision.
8. Limitations
- The ClinicalTrials.gov record does not report posted statistical analyses for the primary endpoint.
- The registry does not report subgroup analyses, baseline characteristics, or detailed survival estimates on this record.
- Overall survival analysis requires appropriate handling of censoring and follow-up duration.
- Interpretation of randomized comparisons depends on the prespecified analysis plan and analysis population.
9. Why This Trial Matters Statistically
| Concept | How it appears in CARMENA |
|---|---|
| Randomized design | Patients were assigned in a randomized parallel-group phase 3 study. |
| Time-to-event endpoint | Overall survival was the primary endpoint. |
| Comparative effectiveness | The trial compared nephrectomy with sunitinib alone. |
| Clinical trial interpretation | The analysis framework must distinguish planned methods from reported results. |
10. Related Tutorials
11. Related Calculators
12. Sources
- ClinicalTrials.gov record: NCT00930033
- PubMed: 34187771
- PubMed: 29860937
- PubMed: 24338498