Condition category
Date applied
Date assigned
Last edited
Prospectively registered
Overall trial status
Recruitment status
No longer recruiting

Plain English Summary

Background and study aims
This study was designed to investigate the effectiveness of a form of major surgery known as extra pleural pneumonectomy (EPP) for patients diagnosed with malignant pleural mesothelioma (a malignant tumour involving the lining of the lung). The benefits considered were longer survival and/or improved quality of life.
Mesothelioma surgery is usually accompanied by chemotherapy and, where appropriate, it is followed by radiotherapy. Because the available knowledge on patients’ outcome was from those who had received all three forms of cancer treatment as a package (chemotherapy, surgery and radiotherapy), it was not possible to determine from the existing evidence whether the surgical component itself was helpful to them.

Who can participate?
Patients 18 years of age or older with pleural mesothelioma, considered suitable for these treatments based on the knowledge available in the early 2000s when the study was being planned, were asked to give written consent to join the study.

What does the study involve?
Participants were given chemotherapy and then had further tests. Their response to chemotherapy and the results of the tests were reviewed by a team of medical specialists. Patients assessed as suitable (in terms of their general health and the extent of the cancer) were invited to consent to be randomly allocated to have EPP surgery, followed by radiotherapy, or to not have EPP surgery.

What are the possible benefits and risks of participating?
Not provided.

Where is the study run from?
The study was conducted in 12 hospitals located throughout the UK. The Clinical Trials and Statistics Unit at The Institute of Cancer Research co-ordinated the study.

When is the study starting and how long is it expected to run for?
The study ran from July 2006 to July 2009.

Who is funding the study?
Cancer Research UK and the June Hancock Mesothelioma Fund.

Who is the main contact?
Professor Tom Treasure

Trial website

Contact information



Primary contact

Prof Tom Treasure


Contact details

Clinical Operation Research Unit
Dept of Mathematics
University College
Taviton Street
United Kingdom

Additional identifiers

EudraCT number number


Protocol/serial number


Study information

Scientific title



Study hypothesis

Added 06/08/09:
To determine whether 50 malignant mesothelioma patients can be randomised to radical surgery versus best palliative care within a year. It will also determine the effects of surgery on survival and quality of life and provided that recruitment & safety data are acceptable, it will be extended to an international randomised trial with the aim of providing definitive data on the value of Extra-Pleural Pneumonectomy (EPP) surgery in the treatment of early stage malignant mesothelioma.

Ethics approval

Not provided at time of registration

Study design

Randomised controlled trial

Primary study design


Secondary study design

Randomised controlled trial

Trial setting


Trial type


Patient information sheet




Prior to randomisation all patients undergo 3 cycles of cisplatin based chemotherapy.
Randomisation arms are with or without extrapleural pneumonectomy (EPP) surgical intervention. Those with EPP will go on to have radical radiotherapy.

Intervention type



Not Specified

Drug names

Primary outcome measures

Not provided at time of registration

Secondary outcome measures

Not provided at time of registration

Overall trial start date


Overall trial end date


Reason abandoned


Participant inclusion criteria

Two phase eligibility:

Registration Eligibility criteria at registration:
1. 18 years of age or older
2. Histologically proven mesothelioma
3. Fit to undergo extrapleural pneumonectomy (EPP) as per British Thoracic Society (BTS) guidelines
4. Fit to undergo the planned post-operative radiotherapy
5. Able to complete Quality of Life questionnaires
6. Able to comply with follow-up requirements
7. Written informed consent for registration
8. Positron emission tomography (PET) or mediastinoscopy negative
9. No distant metastases

Once chemotherapy has been completed a further eligibility criteria is checked to determine continued eligibility for randomisation.
Eligibility criteria for randomisation:
1. Still fulfil eligibility criteria for registration
2. Completion of 3 cycles of chemotherapy
3. Operable disease (T1-3, N0-1, M0)
4. Biopsy proven malignant mesothelioma on histology and immuno-histochemistry
5. Normal renal function
6. World Health Organisation (WHO) performance status 0 or 1
7. Written informed consent for randomisation

Participant type


Age group



Not Specified

Target number of participants

100 (50 in each arm) (Added 06/09/2011: 50 patients in total randomised to the Feasibility Study)

Participant exclusion criteria

1. Predicted post-operative forced expiratory volume in 1 second (FEV1) of less than 40% and carbon monoxide transfer factor (TLCO) of less than 40%
2. Significant pulmonary hypertension
3. Cardiac ejection fraction of less than 40%

Recruitment start date


Recruitment end date



Countries of recruitment

United Kingdom

Trial participating centre

Clinical Operation Research Unit
United Kingdom

Sponsor information


Guy's and St. Thomas' Hospitals NHS Foundation Trust (UK)

Sponsor details

Prof Tom Treasure
Clinical Operation Research Unit
Dept of Mathematics
University College
Taviton Street
United Kingdom

Sponsor type

Hospital/treatment centre



Funder type


Funder name

Cancer Research UK (CRUK) (UK) (Reference number C150 / A3889)

Alternative name(s)


Funding Body Type

private sector organisation

Funding Body Subtype

other non-profit


United Kingdom

Funder name

June Hancock Mesothelioma Research Foundation (No reference number given)

Alternative name(s)

Funding Body Type

Funding Body Subtype


Results and Publications

Publication and dissemination plan

Not provided at time of registration

Intention to publish date

Participant level data

Not provided at time of registration

Results - basic reporting

Publication summary

1. 2006 protocol in
2. 2009 results in
3. 2011 results in

Publication citations

  1. Protocol

    Treasure T, Tan C, Lang-Lazdunski L, Waller D, The MARS trial: mesothelioma and radical surgery., Interact Cardiovasc Thorac Surg, 2006, 5, 1, 58-59, doi: 10.1510/icvts.2005.123430.

  2. Results

    Treasure T, Waller D, Tan C, Entwisle J, O'Brien M, O'Byrne K, Thomas G, Snee M, Spicer J, Landau D, Lang-Lazdunski L, Bliss J, Peckitt C, Rogers S, Marriage Née Denholm E, Coombes G, Webster-Smith M, Peto J, The Mesothelioma and Radical surgery randomized controlled trial: the Mars feasibility study., J Thorac Oncol, 2009, 4, 10, 1254-1258, doi: 10.1097/JTO.0b013e3181ae26ae.

  3. Results

    Treasure T, Lang-Lazdunski L, Waller D, Bliss JM, Tan C, Entwisle J, Snee M, O'Brien M, Thomas G, Senan S, O'Byrne K, Kilburn LS, Spicer J, Landau D, Edwards J, Coombes G, Darlison L, Peto J, , 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, 763-772, doi: 10.1016/S1470-2045(11)70149-8.

Additional files

Editorial Notes