# MARS 2: extended pleurectomy decortication plus chemotherapy versus chemotherapy alone for pleural mesothelioma

Source: https://onco.cc/key-papers/paper-mars-2-lancet-respir-med-2024/  
OnCo record `paper-mars-2-lancet-respir-med-2024` (Key paper). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)"; commercial use needs a licence.

## TL;DR

Adding lung-sparing radical surgery to chemotherapy for pleural mesothelioma did not lengthen life; patients who had surgery lived slightly less long, had more complications and worse quality of life, so routine surgery is no longer recommended.

## Summary

Multicentre randomised trial in the United Kingdom of 335 patients with resectable pleural mesothelioma randomised to extended pleurectomy decortication plus platinum-pemetrexed chemotherapy or chemotherapy alone.

Median overall survival was 19.3 months with surgery against 24.8 months without (hazard ratio 1.28); surgery caused more serious adverse events and worse quality of life in the first year, at higher cost.

## Fields

- Kind: Key paper
- Last checked: 2026-09-17
- Journal: The Lancet Respiratory Medicine
- Year: 2024
- DOI: 10.1016/S2213-2600(24)00119-x
- Authors: Lim E, Waller D, Lau K, et al.
- Findings: Median overall survival 19.3 vs 24.8 months; hazard ratio 1.28 favouring no surgery.; Serious adverse events 3.6 times more common in the surgery arm.
- What it means: Radical surgery for pleural mesothelioma should be confined to trials; effusion is managed with pleurodesis or indwelling catheters and treatment is systemic.
- Caveats: Surgical quality varied across centres; proponents argue selected patients in expert hands may still benefit.; Most patients had epithelioid disease.

## Sources

- Lancet Respir Med 2024: https://doi.org/10.1016/S2213-2600(24)00119-x
- PubMed: https://pubmed.ncbi.nlm.nih.gov/38740044/

## Connected records

- cancers: [Pleural mesothelioma](https://onco.cc/cancers/pleural-mesothelioma/)
- trials: [MARS 2](https://onco.cc/trials/mars-2/)

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