Body Composition Features Predict Overall Survival in Patients With Hepatocellular Carcinoma

Abstract

Objectives: Existing prognostic models for patients with hepatocellular carcinoma (HCC) have limitations. Analytic morphomics, a novel process to measure body composition using computational image-processing algorithms, may offer further prognostic information. The aim of this study was to develop and validate a prognostic model for HCC patients using body composition features and objective clinical information.

Methods: Using computed tomography scans from a cohort of HCC patients at the VA Ann Arbor Healthcare System between January 2006 and December 2013, we developed a prognostic model using analytic morphomics and routine clinical data based on multivariate Cox regression and regularization methods. We assessed model performance using C-statistics and validated predicted survival probabilities. We validated model performance in an external cohort of HCC patients from Parkland Hospital, a safety-net health system in Dallas County.

Results: The derivation cohort consisted of 204 HCC patients (20.1% Barcelona Clinic Liver Cancer classification (BCLC) 0/A), and the validation cohort had 225 patients (22.2% BCLC 0/A). The analytic morphomics model had good prognostic accuracy in the derivation cohort (C-statistic 0.80, 95% confidence interval (CI) 0.71-0.89) and external validation cohort (C-statistic 0.75, 95% CI 0.68-0.82). The accuracy of the analytic morphomics model was significantly higher than that of TNM and BCLC staging systems in derivation (P<0.001 for both) and validation (P<0.001 for both) cohorts. For calibration, mean absolute errors in predicted 1-year survival probabilities were 5.3% (90% quantile of 7.5%) and 7.6% (90% quantile of 12.5%) in the derivation and validation cohorts, respectively.

Conclusion: Body composition features, combined with readily available clinical data, can provide valuable prognostic information for patients with newly diagnosed HCC.

Figure 1

Body composition features as determined by analytic morphomics. (a) Example of identification of spinal vertebral levels that serve as anatomic reference point. (b) Example of fascial envelope (yellow line) and skin outline (red line). (c) Example of the dorsal group muscles (outlined in yellow) defined automatically after delineation of paraspinus lateral seams at specified vertebra points. (d) Example of MATLAB-based 3D image viewer graphical user interface showing the pixel densities which was used to measure the interstitial hounsfeld units at T11 (ITHU). (e) Example of VB2FASCIA or distance between the vertebra to the facial envelope. (f) Example of FASCIAAREA or fascial area.