Bone Densities Assessed by Hounsfield Units at L5 in Computed Tomography Image Independently Predict Hepatocellular...

A previous study identified that bone density (BD) assessed by Hounsfield unit (HU) at T12 in computed tomography (CT) image was a predictor for hepatocellular carcinoma (HCC) development in cirrhotic patients. Here, we conducted a verification study, where clinical variables together with BDs (assessed from three different bone areas: T12, L5, and femur trochanter) were assessed for their predictive values for time-to-HCC development in cirrhotic patients. Univariate Cox proportional hazard analysis showed that age (p = 0.017), T12 BD (p = 0.013) and L5 BD (p = 0.005), but not femur BD, were significant predictors. Multivariate analysis revealed that L5 BD was the only independent factor associated with time-to-HCC development (adjusted p = 0.007). Kaplan-Meier analysis confirmed that BD which was lower than median HU was associated with a shorter time-to-HCC development for both T12 BD and L5 BD (p = 0.001 each). Longitudinal follow-ups for BDs in HCC patients having received serial CT imaging studies unveiled a significantly rapid reduction in BD, right before HCC was diagnosed (p = 0.025 when compared with the average BD reduction rate). In conclusion, BD assessed by HU at L5 was an independent predictor for HCC development in cirrhotic patients. Rapid BD reduction during CT scan follow-ups could serve as a warning sign for HCC development.