Background: Cancer cachexia is a multi-factorial syndrome characterised by an ongoing loss of skeletal muscle mass, with or without a loss of fat mass, which leads to progressive functional impairment. Physical exercise may attenuate the effects of cancer cachexia via several mechanisms, including the modulation of muscle metabolism, insulin sensitivity and levels of inflammation.
Objectives: The primary objective was to determine the effects of exercise, compared to usual care or no treatment, on lean body mass, the main biomarker of cachexia, in adults with cancer. Secondary objectives, subject to the availability of data, were to examine the acceptability and safety of exercise in this setting and to compare effects according to the characteristics of the exercise intervention or patient population.
Search methods: We searched the databases CENTRAL (Issue 6, 2014) , MEDLINE (1946 to June 2014), EMBASE (1974 to June 2014), DARE and HTA (Issue 6, 2014), ISI Web of Science (1900 to June 2014), LILACS (1985 to 28 June 2014), PEDro (inception to 28 June 2014), SciVerse SCOPUS (inception to 28 June 2014), Biosis Previews PreMEDLINE (1969 to June 2014) and Open Grey (inception to 28 June 2014). We also searched for ongoing studies, checked reference lists and contacted experts to seek potentially relevant research.
Selection criteria: We included randomised controlled trials (RCTs) in adults meeting the clinical criteria for cancer cachexia comparing a programme of exercise as a sole or adjunct intervention to no treatment or an active control. We imposed no language restriction.
Data collection and analysis: Two review authors independently assessed titles and abstracts of articles for relevance and extracted data on study design, participants, interventions and outcomes from potentially relevant articles.
Main results: We screened 3154 individual references, of which we removed 3138 after title screening and read 16 in full. We found no trials that met the inclusion criteria.
Authors' conclusions: There is insufficient evidence to determine the safety and effectiveness of exercise for patients with cancer cachexia. Randomised controlled trials (i.e., preferably parallel-group or cluster-randomised trials) are required to test the effectiveness of exercise in this group. There are ongoing studies on the topic, so we will update this review to incorporate the findings.