The Impact of Muscle and Adipose Tissue on Long-term Survival in Patients With Stage I to III Colorectal Cancer.

Background: Computed tomography-derived body composition parameters are emerging prognostic factors in colorectal cancer.

Objective: This study aimed to determine the roles of sarcopenia, myosteatosis, and obesity as independent and overlapping parameters in stage I to III colorectal cancer.

Design: This is a retrospective cohort study from a prospectively collected database. Multivariate Cox proportional hazards models were performed to assess the associations between body composition parameters and survival.

Settings: All patients were seen in a tertiary care cancer center.

Patients: Adult patients with stage I to III colorectal cancer, undergoing curative resection from 2007 to 2009, were included.

Intervention: Computed tomography-derived quantification of skeletal muscle and adipose tissues was used to determine population-specific cutoffs for sarcopenia, myosteatosis, and total adiposity.

Main Outcome Measures: Primary outcome measures were overall, recurrence-free, and cancer-specific survival.

Results: In the 968 patients included, there were a total of 254 disease recurrences and 350 deaths. Body mass index and CT-derived measures of adiposity did not result in worse survival outcomes. Sarcopenia was independently predictive of worse overall (HR, 1.45; 95% CI, 1.16-1.84), recurrence-free (HR, 1.32; 95% CI, 1.00-1.75), and cancer-specific survival (HR, 1.46; 95% CI, 1.09-1.94) in a multivariate model. Myosteatosis was also independently predictive of overall survival (HR, 1.53; 95% CI, 1.19-1.97). In a model considering joint effects of sarcopenia and myosteatosis, the presence of both predicted the worst overall (HR, 2.23; 95% CI, 1.62-3.06), recurrence-free (HR, 1.53; 95% CI, 1.06-2.21), and cancer-specific survival (HR, 2.40; 95% CI, 1.69-3.42) in a multivariate model.

Limitations: The limitations of this study are inherent in retrospective observational studies.

Conclusions: Sarcopenia and myosteatosis are independent predictors of worse survival in stage I to III colorectal cancer, and their joint effect is highly predictive of reduced overall, recurrence-free, and cancer-specific survival. See Video Abstract at http://links.lww.com/DCR/A923.