MARS
Mesothelioma and Radical Surgery (MARS) randomised feasibility study: extra-pleural pneumonectomy versus no extra-pleural pneumonectomy for malignant pleural mesothelioma
N = 50
- Population
- Adults (18 years or older) with pathologically confirmed malignant pleural mesothelioma judged fit enough for trimodal therapy; randomised after induction platinum-based chemotherapy
- Design
- Multicentre randomised controlled feasibility study in 12 UK hospitals, registered as ISRCTN95583524, the number the paper prints (it prints no NCT id, and a ClinicalTrials.gov search for that ISRCTN number found none). All registered patients first had induction platinum-based chemotherapy; after further consent they were randomised 1:1 (centrally, permuted blocks stratified by surgical centre) to extra-pleural pneumonectomy (EPP) followed by postoperative hemithorax irradiation, or to no EPP. 112 patients were registered and 50 randomised (24 EPP, 26 no EPP) between 1 October 2005 and 3 November 2008. Open label; analyses by intention to treat. The paper describes the study as a feasibility study (main endpoints: feasibility of randomising 50 patients in 1 year, proportion randomised who received treatment, proportion of registered patients randomised, perioperative mortality and quality of life); it states that a trial powered for overall survival would have needed 670 patients.
- Arms
- No EPP (control, n = 26): No extra-pleural pneumonectomy after induction platinum-based chemotherapy (continued best care)
- EPP (experimental, n = 24): Extra-pleural pneumonectomy followed by postoperative hemithorax irradiation, after induction platinum-based chemotherapy
- People
- Treasure T, MARS trialists
OSHR 1.90 (95% CI 0.92–3.93)Δ median OS−5.1 monthsOSHR 2.75 (95% CI 1.21–6.26)Δ 12-month OS−20.9 points
Show the numbers
| Endpoint | Analysis | EPP | No EPP | Effect |
|---|---|---|---|---|
| OS | finalTreasure 2011 | median 14.4 months | median 19.5 months | HR 1.90 (95% CI 0.92–3.93)P=0.082Unadjusted hazard ratio for EPP versus no EPP (a value above 1 means a higher hazard of death with EPP); exact log-rank p-value. The intervals printed beside the medians are 5.3-18.7 months (EPP) and 13.4 months to not yet reached (no EPP); they are not labelled as confidence intervals in the abstract, so they are not entered as such. Survival is counted from randomisation, which followed induction chemotherapy. MARS was a feasibility study of 50 randomised patients. |
| OS | finalTreasure 2011 | — | — | HR 2.75 (95% CI 1.21–6.26)P=0.016Hazard ratio for EPP versus no EPP after adjustment for sex, histological subtype, stage and age at randomisation. |
| OS | finalTreasure 2011 | 52.2% at 12 mo (30.5–70.0%) | 73.1% at 12 mo (51.7–86.2%) | 12-month survival; the paper gives the difference as 18.0 percentage points (95% CI -1.8 to 43.9). 30 of 50 patients had died at a median follow-up from randomisation of 24.7 months (EPP 17, no EPP 13). |
| Endpoint | Analysis | EPP | No EPP | Effect |
|---|---|---|---|---|
| OS | finalTreasure 2011 | median 14.4 months | median 19.5 months | HR 1.90 (95% CI 0.92–3.93)P=0.082Unadjusted hazard ratio for EPP versus no EPP (a value above 1 means a higher hazard of death with EPP); exact log-rank p-value. The intervals printed beside the medians are 5.3-18.7 months (EPP) and 13.4 months to not yet reached (no EPP); they are not labelled as confidence intervals in the abstract, so they are not entered as such. Survival is counted from randomisation, which followed induction chemotherapy. MARS was a feasibility study of 50 randomised patients. |
| OS | finalTreasure 2011 | — | — | HR 2.75 (95% CI 1.21–6.26)P=0.016Hazard ratio for EPP versus no EPP after adjustment for sex, histological subtype, stage and age at randomisation. |
| OS | finalTreasure 2011 | 52.2% at 12 mo (30.5–70.0%) | 73.1% at 12 mo (51.7–86.2%) | 12-month survival; the paper gives the difference as 18.0 percentage points (95% CI -1.8 to 43.9). 30 of 50 patients had died at a median follow-up from randomisation of 24.7 months (EPP 17, no EPP 13). |
Data table
| Endpoint | HR | 95% CI |
|---|---|---|
| OS | 1.9 | 0.92–3.93 |
| OS | 2.75 | 1.21–6.26 |
- EPP (experimental)
- No EPP (control)
Median-only curves assume a constant hazard (exponential) and fit plateaus, as seen with some immunotherapies, poorly.
Data table (modelled values)
| Months | EPP | No EPP |
|---|---|---|
| 0 | 100.0% | 100.0% |
| 12 | 56.1% | 65.3% |
| 24 | 31.5% | 42.6% |
| 37 | 16.8% | 26.8% |
| 49 | 9.5% | 17.5% |
Appears in
Sources
Treasure T, Lang-Lazdunski L, Waller D, Bliss JM, Tan C, Entwisle J, et al. Extra-pleural pneumonectomy versus no extra-pleural pneumonectomy for patients with malignant pleural mesothelioma: clinical outcomes of the Mesothelioma and Radical Surgery (MARS) randomised feasibility study. Lancet Oncol. 2011;12(8):763-72.