Prevalence and predictive value of pre-therapeutic sarcopenia in cancer patients: A systematic review

To assess the prevalence of sarcopenia before cancer treatment and its predictive value during the treatment.We searched MEDLINE via PubMed for articles published from 2008 to 2016 that reported prospective observational or interventional studies of the prevalence of pre-therapeutic sarcopenia and its consequences in adults with cancer who were 18 years or older. Two independent reviewers selected articles based on titles and/or abstracts before a complete review. Sarcopenia had to be measured before cancer treatment. Methods recommended by consensuses (CT scan, MRI, dual X-ray absorptiometry or bio-impedancemetry) to assess sarcopenia were considered. Characteristics of the studies included the prevalence of pre-therapeutic sarcopenia and the prognostic value for outcomes during the cancer treatment.We selected 35 articles involving 6894 participants (in/out patients, clinical trials). The mean age ranged from 53 to 69.6 years. Pre-therapeutic sarcopenia was found in 38.6% of patients [95% CI 37.4-39.8]. Oesophageal and small-cell lung cancers showed the highest prevalence of pre-therapeutic sarcopenia. Pre-therapeutic sarcopenia was significantly and independently associated with post-operative complications, chemotherapy-induced toxicity and poor survival in cancer patients.Pre-therapeutic sarcopenia is highly prevalent in cancer patients and has severe consequences for outcomes of cancer patients.