The impact of myosteatosis on outcomes following surgery for gastro-intestinal malignancy: A systematic review and meta-analysis.

Abstract

e15540 Background: Recent research has demonstrated the impact that body composition parameters can have on the outcomes following cancer surgery. Adipose tissue deposition in muscle, known as myosteatosis, can be detected on pre-operative imaging. This systematic review aims to analyse the impact of pre-operative myosteatosis on long-term outcomes following surgery for gastro-intestinal malignancy. Methods: Using MeSH terms, a systematic search of the databases PubMed MEDLINE, EMBASE, Cochrane, CINAHL and AMED was performed. Studies were included if they reported hazard ratios (HR) analysing the impact of pre-operatively defined myosteatosis, or similar term, on the long-term outcomes following surgery for gastro-intestinal malignancy. A total of 39 full texts articles were reviewed for inclusion, with 19 being included after the inclusion criteria were applied. A sub-group analysis was performed for those studies reporting outcomes for colorectal cancer patients only. Results: The total number of included patients across all studies was 14,481. Patients with myosteatosis had a significantly poorer overall survival, according to univariate (HR 1.82, 95% CI 1.67 – 1.99) and multivariable (HR 1.66, 95% CI 1.49 – 1.86) analysis. This was also demonstrated with regards to cancer-specific survival (univariate HR 1.62, 95% CI 1.18 – 2.22, multivariable HR 1.73, 95% CI 1.48 – 2.03) and recurrence-free survival (univariate HR 1.28, 95% CI 1.10 – 1.48, multivariable HR 1.38, 95% CI 1.07 – 1.77). Conclusions: This review demonstrates that patients with pre-operative myosteatosis have poorer long-term outcomes following surgery for gastro-intestinal malignancy. Therefore, myosteatosis should be used for pre-operative optimisation and as a prognostic tool before surgery. More standardised definitions of myosteatosis and further cohort studies of patients with non-colorectal malignancies are required.