Abdominal adipose tissue radiodensity predicts survival after colorectal cancer

Adipose tissue radiodensity is significantly associated with the risk of death in patients with nonmetastatic colorectal cancer (CRC), independent of body mass index and changes in body weight, results of a study have shown.

The authors quantified radiodensities of visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) from diagnostic computed tomography images in 3,023 patients with stage I‒III CRC. Follow-up images were available for 1,775 patients.

The associations of at-diagnosis values and of longitudinal changes in VAT and SAT radiodensities with risks of death were assessed using Cox proportional hazards models and restricted cubic splines after adjusting for potential confounders, including body size and comorbidities.

VAT and SAT radiodensities showed a linear relationship with all-cause mortality (VAT radiodensity: hazard ratio [HR] for death per standard deviation [SD] increase, 1.21, 95 percent confidence interval [CI], 1.11‒1.32; SAT radiodensity: HR, 1.18, 95 percent CI, 1.11‒1.26).

Moreover, changes in adipose tissue radiodensity demonstrated curvilinear associations with mortality risks. Compared with maintaining radiodensity within 1 SD of baseline, the HR for an increase in VAT radiodensity of at least 1 SD was 1.53 (95 percent CI, 1.23‒1.90), while that for a decrease of at least 1 SD was nonsignificant at 1.11 (95 percent CI, 0.84‒1.47).

Increases in SAT radiodensities (HR, 1.88, 95 percent CI, 1.48‒2.40), but not decreases (HR, 1.20, 95 percent CI, 0.94‒1.54), also significantly increased the risk of death relative to no change in radiodensity.

“Adipose tissue radiodensity may have prognostic importance for CRC survival,” the authors said. “Lower radiodensity is indicative of larger adipocytes, while higher radiodensity may represent adipocyte atrophy, inflammation, or oedema.”