Meta-analysisindependent cross-checkfull text checked★ key study I-CHM-02 in-depth review
Radiotherapy after breast-conserving surgery halves recurrence
Effect of radiotherapy after breast-conserving surgery on 10-year recurrence and 15-year breast cancer death: meta-analysis of individual patient data for 10,801 women in 17 randomised trials.
Overview
EBCTCG. Lancet 2011 · PMID 22019144 · DOI 10.1016/S0140-6736(11)61629-2
Recurrence within 10 years fell from 35% to 19%, and breast-cancer deaths within 15 years from 25% to 21%.
Does the study support the specific claim? No · Methodological quality: high
Plain-language summary
Study explained simply
- What did the researchers want to find out?
Measure radiotherapy benefit.
- How was the study done?
IPD meta-analysis.
- How many people, animals or samples were studied?
10,801 women.
- What was actually found?
Recurrence halved; breast-cancer deaths about one-sixth lower; deaths from any cause at 15 years 3.0 percentage points lower.
- How large was the observed effect?
-15.7% recurrence; -3.8% death.
- What do the results mean in everyday life?
Radiotherapy markedly lowers the chance the cancer returns.
- What are the study's limitations?
Older techniques; risk groups derived from the same data; in low-risk node-negative women the gain in survival was small and uncertain.
- What does it say about Elawady's specific claim?
Benefit side.
- Do the results apply to Germany and Europe?
High.
- What can explicitly not be concluded from this study?
Individual benefit size without risk factors.
Scientific in-depth review
1. Full reference
- Authors
- EBCTCG
- Journal
- Lancet
- Year
- 2011
- Identifier
- PMID 22019144 DOI 10.1016/S0140-6736(11)61629-2
- Verification
- verified – PubMed esummary + efetch 2026-10-25
- Retracted
- no
- Corrections
- none
- Extent checked
- full text
- Conflicts of interest and funding
EBCTCG core funding from Cancer Research UK, British Heart Foundation, UK Medical Research Council (no role in study); all secretariat and writing-committee members declare no conflicts; CTSU staff policy excludes honoraria.
2. Research question
Effect of radiotherapy after breast-conserving surgery on recurrence and breast-cancer death.
3. Study design and population
- Study design
- Meta-analysis – IPD meta-analysis of 17 randomised trials
- Population
Women after breast-conserving surgery
- Country
International
- Period
Trials begun 1976-1999; follow-up to 30 Sept 2006; median follow-up 9.5 years (25% >10 years)
- Sample size
10,801 women in 17 trials (8337 with pathological nodal status: 7287 pN0, 1050 pN+); 3143 deaths
- Inclusion and exclusion criteria
Unconfounded randomised trials begun before 2000 of radiotherapy vs no radiotherapy after breast-conserving surgery for invasive cancer; 2 eligible trials (133 women) without available data
4. Methods and endpoints
- Exposure / intervention
Radiotherapy
- Comparator
No radiotherapy
- Endpoints
10-year recurrence; 15-year breast-cancer death
- Statistical methods
IPD meta-analysis
5. Actual results
- Results
10-year any first recurrence 19.3% vs 35.0% (absolute reduction 15.7%, 95% CI 13.7-17.7; recurrence RR 0.52, 0.48-0.56). 15-year breast cancer death 21.4% vs 25.2% (absolute 3.8%, 1.6-6.0; RR 0.82, 0.75-0.90). 15-year all-cause mortality absolute reduction 3.0% (0.6-5.4, 2p=0.03); non-breast-cancer mortality without recurrence RR 1.09 (0.97-1.22, not significant). pN0: recurrence 31.0% -> 15.6% (15.4%, 13.2-17.6), breast cancer death 20.5% -> 17.2% (3.3%, 0.8-5.8). pN0 predicted-benefit groups: breast cancer death reduction 7.8% (3.1-12.5) large, 1.1% (-2.0 to 4.2) intermediate, 0.1% (-7.5 to 7.7) lower. pN+: recurrence 63.7% -> 42.5% (21.2%, 14.5-27.9), breast cancer death 51.3% -> 42.8% (8.5%, 1.8-15.2). About one breast cancer death avoided by year 15 per four recurrences avoided by year 10.
- Absolute risks
15-year breast cancer death -3.8 percentage points overall (-8.5 pN+; -3.3 pN0); 15-year all-cause death -3.0 percentage points; 10-year recurrence -15.7 percentage points
- Authors' conclusion
Radiotherapy halves recurrence and reduces breast-cancer death by about a sixth.
6. Strengths
- Randomised IPD from nearly all eligible trials
- Absolute risks with 95% CIs, incl. all-cause mortality
- Harms side partly captured (non-breast-cancer mortality)
7. Weaknesses
- Older radiotherapy, surgery, pathology and systemic therapy (trials 1976-99); margins would differ with modern pathology (authors)
- Risk-prediction categories derived from the same data, not externally validated (authors)
- Recurrence follow-up incomplete beyond year 10
- Non-breast-cancer mortality and second cancers reported elsewhere
- No formal per-trial risk-of-bias assessment reported
8. Risk of bias
- Orienting tool
- AMSTAR 2 (adapted to collaborative IPD meta-analysis)
- Type of assessment
- structured assessment based on the full text by a single reviewer (no formal double review)
- Full formal assessment
- no
- Overall risk of bias
- low
- Rationale
Unchanged overall low risk of bias for main estimates; subgroup prediction categories are exploratory. Single-reviewer structured judgement from the full text; a complete formal assessment requires two independent reviewers and the review/study protocol.
| Domain | Judgement | Rationale |
|---|---|---|
| Item 2 protocol (critical) | some concerns | Methods as in previous EBCTCG reports; preliminary results circulated to collaborators; no registered protocol cited. |
| Item 4 comprehensive search (critical) | low | All trials begun before 2000 sought; 17 available, 2 small trials (133 women) unavailable and declared. |
| Item 7 excluded studies (critical) | low | Unavailable/excluded trials named (table 1 footnote, webappendix). |
| Item 9 RoB of included RCTs (critical) | some concerns | No formal tool reported; restriction to unconfounded randomised trials and IPD ITT analysis mitigates. |
| Item 11 appropriate synthesis (critical) | low | Stratified log-rank and Poisson regression on IPD. |
| Item 13 RoB considered in interpretation (critical) | low | Authors caution about internal derivation of risk groups and changes in practice. |
| Item 15 publication bias (critical) | low | Near-complete IPD of all eligible trials. |
| Item 16 conflicts of interest | low | Declared, none for writing committee. |
Full-text review (25 October 2026): Added trial period, follow-up, pN0/pN+ counts, 2 unavailable trials, recurrence RR 0.52 and breast-cancer-death RR 0.82 with CIs, 15-year all-cause mortality reduction 3.0% (0.6-5.4), non-breast-cancer mortality RR 1.09 (NS), predicted-benefit subgroup mortality results, author limitations. Bias overall unchanged (low).
9. Assessment of the statistical interpretation
Recurrence halved; breast cancer mortality reduced by about a sixth; 15-year all-cause mortality also lower (3.0 percentage points), with a small non-significant excess of non-breast-cancer mortality. Mortality benefit concentrated in higher-risk women; in low/intermediate predicted-benefit node-negative women the mortality reduction was not significant.
10. Relevance to the specific claim
Counterweight to Darby's 7.4%/Gy; shows radiotherapy reduces recurrence ('the body will reactivate elsewhere' is not what happens with treatment).
11. Independent contrary findings
Harm side in A-CHM-04, I-CHM-06.
12. Transferability to Germany and Europe
High.
13. Overall methodological judgement
High-certainty randomised evidence of recurrence and mortality benefit, including all-cause mortality; benefit varies with baseline risk.
| Multidimensional assessment | |
|---|---|
| Authenticity of the source | verified |
| Methodological quality | high |
| Risk of bias | low |
| Precision of results | high |
| Directness | direct |
| Reproducibility | replicated |
| Consistency with the overall evidence | consistent |
| Regional transferability | high |
| Adequacy of the interpretation (by the archive) | not applicable |
14. Open questions
Absolute benefit with modern techniques and in low-risk subgroups (e.g. older women with tamoxifen).
15. Linked fact checks
- The archive's 19 chemo/radiation studies are presented on the homepage as 'scientific studies confirming what Dr. Diaa proposed'; the harm-only study selection implies that the harms of chemotherapy and radiotherapy outweigh their benefits. – Studies contradicting or limiting the claim
- After breast-cancer radiotherapy, the rate of major coronary events rises by 7.4% for every Gray of mean radiation dose to the heart, linearly and without threshold (Darby 2013). – Studies contradicting or limiting the claim
- Chemotherapy and tumour-removal surgery do not address root causes; the body will reactivate its 'defensive plan' elsewhere, so these treatments should be avoided. – Studies contradicting or limiting the claim
- Cancer patients should not take chemotherapy, radiotherapy or biological therapy (or should stop them) and follow the Tayebat system instead; 'we are against the word medicine'. – Studies contradicting or limiting the claim
- Oncology only buys time: 'survival rates' are meaningless, patients die during treatment, and early diagnosis only makes you 'die early'. – Studies contradicting or limiting the claim