This is a plain English summary of an original research article
People who receive exercise training following surgery for lung cancer can walk about 57 metres further in six minutes than controls who did not exercise. After surgery like this to remove all or part of a lung, people typically manage about 500 metres in six minutes on the test, and anything above 20 metres is considered a worthwhile improvement. Exercise also increases leg strength and quality of life.
A decline in physical fitness is a common and debilitating effect of lung resection. Exercise training is already recommended in the rehabilitation of many chronic conditions including obstructive lung disease.
This Cochrane update reviewed eight trials exploring the effect of combined aerobic and resistance exercise after lung cancer surgery. Despite being of small size (450 participants in total), the trials demonstrated consistent and meaningful improvements in exercise capacity.
There is a need to improve understanding of the best programme format, and how exercise can be tailored alongside other rehabilitation measures to give the best outlook for health and wellbeing after lung cancer surgery.
Why was this study needed?
Lung cancer is the third most common cancer in the UK, with around 47,200 new diagnoses every year. About eight per cent of people are suitable for curative surgery to remove the tumour and surrounding lung tissues.
Around 40% of people receiving curative resection will survive for at least five years. Yet physical debilitation, with fatigue and breathlessness, is common and perceived by many to be the most undesirable effect of surgery.
Exercise training is established in the management of many chronic respiratory conditions, as well as benefitting the recovery of certain cancers like breast and prostate, but less is known about its benefits or harms after lung cancer surgery.
This Cochrane review aimed to combine the results of new and old trials that evaluated exercise training following surgery in non-small cell lung cancer.
What did this study do?
This updated review added five randomised controlled trials to the three included in a previous review completed in 2013. The eight trials included 450 patients (40% women) who had undergone lung resection for non-small cell lung cancer (with or without chemotherapy) and been allocated to control or exercise training, starting within 12 months of surgery.
Studies varied in the extent of lung resection and used either keyhole or open surgical approaches. Six studies assessed combined aerobic and resistance exercise, and two involved inspiratory muscle training. Session frequency ranged from two to five days per week, with exercise at variable intensity. Intervention duration varied from 4 to 20 weeks. Control groups received standard outpatient care, with two studies including breathing exercises or exercise instruction.
Participants and researchers were aware of study allocation, which introduces some uncertainty in outcome reporting. Two studies came from the UK. All were published from 2011 onwards.
What did it find?
- People who received exercise training could walk an average of 57 metres further (95% confidence interval [CI] +34m to +80m) in six minutes compared with controls. This exceeded the clinically important difference of 22 to 42 metres. The evidence was high certainty, based on five studies (182 people) with similar direction of effect.
- Peak oxygen consumption during exercise was also higher than controls (mean difference in V02max, 2.97 ml/kg/min, 95% CI 1.93 to 4.02). This was moderate certainty evidence from four trials (135 people).
- There was moderate certainty evidence that exercise improved the strength of the quadriceps muscle (standard mean difference [SMD] 0.75, 95% CI 0.4 to 1.2; four studies, 133 people).
- Four trials reported on adverse effects, with one trial reporting a single case of hip fracture in the exercise group.
What does current guidance say on this issue?
The NICE lung cancer guideline (2019) gives recommendations on assessing people with non-small cell lung cancer for surgery with curative intent but no advice on exercise training. People are considered suitable for surgery if they have good existing exercise tolerance and normal lung function.
NICE recommends walking tests and cardiopulmonary exercise testing to measure oxygen uptake in people considered at risk of shortness of breath after surgery. Good prior function is considered to be at least 400m walked in six minutes and oxygen uptake above 15ml/kg/minute.
What are the implications?
This review shows consistent effects across several studies, and new trials confirm that combined aerobic and resistance training can give an important improvement in exercise capacity after lung resection for non-small cell lung cancer.
The authors suggest that following lung resection, referral for exercise programmes should be considered, as is the case for various other chronic lung and cardiovascular conditions. They warn that because of the small risk of increased falls, participants are offered balance training and supervision when needed.
Citation and Funding
Cavalheri V, Burtin C, Formico VR et al. Exercise training undertaken by people within 12 months of lung resection for non‐small cell lung cancer. Cochrane Database Syst Rev. 2019;(6):CD009955.
This review was supported by Curtin University, Perth, Australia, and by Cancer Council Western Australia.
Cancer Research UK. Lung cancer statistics. London: Cancer Research UK; (undated).
NICE. Lung cancer: diagnosis and management. NG122. London: National Institute for Health and Care Excellence; 2019.
NICE. Physical activity: exercise referral schemes. PH54. London: National Institute for Health and Care Excellence; 2014.
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