Randomised controlled trialindependent cross-checkabstract checked★ key study I-CHM-120 standard review
Chemotherapy after pancreatic cancer surgery
Adjuvant chemotherapy with gemcitabine and long-term outcomes among patients with resected pancreatic cancer: the CONKO-001 randomized trial.
Overview
Oettle H et al.. JAMA 2013 · PMID 24104372 · DOI 10.1001/jama.2013.279201
Chemotherapy after surgery doubled 5-year survival (21% vs 10%) compared with surgery alone.
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?
Test chemotherapy after pancreatic surgery
- How was the study done?
Randomised trial
- How many people, animals or samples were studied?
354 patients
- What was actually found?
Longer survival with chemotherapy
- How large was the observed effect?
5-y OS 20.7% vs 10.4%
- What do the results mean in everyday life?
Even in a hard-to-treat cancer, chemotherapy saves some lives
- What are the study's limitations?
Open-label
- What does it say about Elawady's specific claim?
Contradicts 'chemo cannot work because of fibrosis'
- Do the results apply to Germany and Europe?
High
- What can explicitly not be concluded from this study?
Cannot promise cure for an individual
Scientific in-depth review
1. Full reference
- Authors
- Oettle H et al.
- Journal
- JAMA
- Year
- 2013
- Identifier
- PMID 24104372 DOI 10.1001/jama.2013.279201
- Verification
- verified – PubMed efetch 2026-10-26 (PublicationType and CommentsCorrections checked); Crossref 2026-10-26
- Retracted
- no
- Corrections
- none
- Extent checked
- abstract only
- Conflicts of interest and funding
Not stated in abstract (non-US-government support).
2. Research question
Does adjuvant gemcitabine after complete resection of pancreatic cancer improve overall survival?
3. Study design and population
- Study design
- Randomised controlled trial – Multicentre open-label randomised phase III trial
- Population
Patients after macroscopically complete resection of pancreatic cancer
- Country
Germany, Austria
- Period
1998-2004; follow-up to Sept 2012 (median 136 months)
- Sample size
368 randomised; 354 analysed
- Inclusion and exclusion criteria
Complete resection; stratified by stage, nodes, resection status
4. Methods and endpoints
- Exposure / intervention
Gemcitabine for 6 months
- Comparator
Observation
- Endpoints
DFS (primary), OS, safety
- Statistical methods
HRs; Kaplan-Meier
5. Actual results
- Results
Median DFS 13.4 vs 6.7 months (HR 0.55, 0.44-0.69); OS HR 0.76 (0.61-0.95), P=.01; 5-year OS 20.7% vs 10.4%; 10-year OS 12.2% vs 7.7%.
- Absolute risks
5-year OS +10.3 percentage points; 10-year +4.5 points
- Authors' conclusion
Adjuvant gemcitabine increased overall and disease-free survival compared with observation.
6. Strengths
- Randomised against observation
- Very long follow-up
7. Weaknesses
- Open-label
- Modest sample
8. Risk of bias
- Orienting tool
- RoB 2
- Type of assessment
- simplified assessment (abstract only)
- Full formal assessment
- no
- Overall risk of bias
- low
- Rationale
Randomised; OS objective.
9. Assessment of the statistical interpretation
OS HR 0.76 (0.61-0.95) log-symmetric; NNT about 10 for one extra 5-year survivor (stats/C-CHM-09_benefit_harm.py, C-CHM-11.py).
10. Relevance to the specific claim
In pancreatic cancer, the textbook stroma-rich ('fibrotic') tumour, chemotherapy after surgery doubled 5-year survival and halved early recurrence: stroma does not make chemotherapy futile, and surgery plus chemotherapy does not lead to the cancer 'reactivating' more.
11. Independent contrary findings
None.
12. Transferability to Germany and Europe
Directly applicable (European trial).
13. Overall methodological judgement
Strong randomised evidence of chemotherapy benefit in a fibrotic tumour.
| Multidimensional assessment | |
|---|---|
| Authenticity of the source | verified |
| Methodological quality | high |
| Risk of bias | low |
| Precision of results | moderate |
| 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
None.
15. Linked fact checks
- 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 cells resist chemotherapy because of their fibrotic interstitial (stromal) environment; fibrosis strangles cells, which then turn cancerous and resist chemo and radiation. – 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