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
LACC was a randomized parallel-group clinical trial evaluating surgical approaches for cervical cancer. The registry reports an enrollment of 636 participants and a primary endpoint of disease-free survival at 5 years from surgery.
| Feature | LACC |
|---|---|
| NCT ID | NCT00614211 |
| Title | Laparoscopic Approach to Cervical Cancer |
| Status | COMPLETED |
| Phase | NA |
| Condition | Cervical Cancer |
| Design | Randomized, parallel assignment, open-label |
| Primary purpose | Treatment |
2. Clinical Question
Population
Patients with cervical cancer enrolled in the LACC study.
Intervention
Total laparoscopic or robotic radical hysterectomy.
Comparator
Total abdominal radical hysterectomy.
Primary question
Does the laparoscopic or robotic surgical approach produce comparable disease-free survival to abdominal radical hysterectomy?
3. Trial Design
636 patients
Abdominal surgery
Laparoscopic/robotic surgery
5-year DFS
Total Abdominal Radical Hysterectomy
Comparator surgical procedure.
Total Laparoscopic or Robotic Radical Hysterectomy
Intervention surgical procedure.
4. Endpoints
| Endpoint | Definition |
|---|---|
| Disease free survival | 5 years from surgery; compare treatment equivalence. |
5. Planned Analysis
The primary endpoint was disease-free survival at 5 years from surgery. For randomized time-to-event endpoints such as disease-free survival, statistical analysis commonly involves estimation of event-free survival over time, comparison between randomized groups, and estimation of a relative treatment effect with confidence intervals.
The ClinicalTrials.gov record does not report posted statistical analyses or endpoint results for this trial.
6. Statistical Methodology
Time-to-event analysis
Disease-free survival is a time-to-event outcome. Analysis typically accounts for patients who have not experienced an event by the end of follow-up through censoring, allowing follow-up information from all eligible participants to contribute to the estimate.
Equivalence interpretation
The registry describes the primary endpoint as comparing treatment equivalence. Equivalence questions differ from superiority questions because the goal is not simply to show one approach has fewer events. Instead, the analysis must evaluate whether the difference between approaches falls within a prespecified acceptable range.
Superiority: Is one treatment better than another?
Equivalence: Are two treatments sufficiently similar within predefined limits?
7. Statistical Methods Explained
Why is disease-free survival analyzed as a time-to-event endpoint?
Disease-free survival incorporates both whether an event occurs and when it occurs. This provides more information than simply comparing the percentage of patients with events at one fixed time point.
Why does randomization matter?
Random assignment helps balance known and unknown patient characteristics between groups, allowing differences in outcomes to be attributed more directly to the assigned surgical approaches.
What makes equivalence analysis different?
An equivalence analysis requires a predefined margin describing how much difference between approaches is considered clinically acceptable.
Why are confidence intervals important?
Confidence intervals describe the uncertainty around an estimated treatment difference and help determine whether the observed difference is compatible with the prespecified equivalence framework.
Why can missing follow-up matter?
Loss to follow-up and censoring assumptions can influence time-to-event analyses. The validity of conclusions depends on appropriate handling of follow-up information.
8. Limitations
- The registry does not report posted statistical analyses.
- The registry does not report primary endpoint results.
- Detailed subgroup analyses, baseline tables, and additional outcome summaries are not reported in the ClinicalTrials.gov record.
- Interpretation of disease-free survival depends on the prespecified equivalence framework and analysis assumptions.
9. Why This Trial Matters Statistically
LACC illustrates several important concepts in clinical trial methodology.
| Concept | Application |
|---|---|
| Randomization | Comparison of two surgical approaches using randomized allocation. |
| Parallel design | Participants assigned to one of two treatment groups. |
| Time-to-event analysis | Disease-free survival measured over time. |
| Equivalence testing | Primary question focused on treatment equivalence. |
| Censoring | Important consideration for survival-type endpoints. |
10. Related Tutorials
11. Related Calculators
12. Sources
- ClinicalTrials.gov record: NCT00614211