Automated three-dimensional body composition analysis identifies visceral adipose tissue radiodensity as a predictor of mortality and recurrence in colorectal cancer.

BACKGROUND

Artificial intelligence enables automated three-dimensional (3D) volumetric body composition (BC) analysis from computed tomography (CT), opposed to single third lumbar vertebra (L3) slices alone. This study aimed to identify relationships between 3D BC and postoperative colorectal cancer (CRC) outcomes utilising Voronoi Health Analytics' Data Analysis Facilitation Suite software.

METHOD: Abdominopelvic skeletal muscle (SM), subcutaneous, and visceral adipose tissue volume and radiodensity were quantified from preoperative CT in 750 patients undergoing CRC resection. Non-contrast enhanced muscle, subcutaneous and visceral adipose tissue radiodensity (Hounsfield units) were adjusted using institution-specific correction values. Volumes were divided by abdominopelvic length, and (height)2, providing size-adjusted indices. Sex-specific cut-offs were defined for BC. Multivariate Cox regression assessed overall, and disease-free survival.

RESULTS

Sarcopenia [HR 1.389 (1.071-1.800), p = 0.013], myosteatosis [HR 1.526 (1.163-2.002), p = 0.002], visceral obesity [HR 2.020 (1.458-2.798), p <0.001], subcutaneous adipose tissue quantity depletion [HR 1.499 (1.117-2.011), p = 0.007], and elevated visceral adipose tissue radiodensity [HR 1.728 (1.171-2.548) p = 0.006] predicted poorer overall survival. Sarcopenia [HR 1.513 (1.019-2.247), p = 0.040] and elevated visceral adipose tissue radiodensity [HR 1.763 (1.148-2.708), p = 0.010] predicted disease recurrence. Elevated visceral adipose was significantly associated with T4 tumour stage [RR 1.621 (1.211-2.489), p = 0.004]; and lymphovascular invasion [RR 1.472 (1.043-2.078), p = 0.030].

CONCLUSION

As established in studies using L3 CT-slices, sarcopenia and myosteatosis in the 3D abdominopelvic region also predict CRC survival outcomes. Whilst further validation is required, elevated abdominopelvic visceral adipose tissue radiodensity is a potentially novel predictor of both mortality and recurrence. This was linked to a more aggressive tumour phenotype in this study.