Prognostic Impact of Osteopenia in Patients Who Underwent Living Donor Liver Transplantation for Hepatocellular Carcinoma

Background Osteopenia, loss of bone mineral density (BMD), was recently identified to be independently associated with early marker of deconditioning that precedes sarcopenia in patients with hepatocellular carcinoma (HCC). The aim of this study was to clarify the impact of osteopenia as the risk factor for mortality after living donor liver transplantation (LDLT) compared with already-reported biological markers. Methods Data were collected retrospectively for all consecutive patients who underwent LDLT for HCC at our institution between January 1998 and December 2015. BMD was evaluated with computed tomographic measurement of pixel density in the midvertebral core of the 11th thoracic vertebra. Data related to clinicopathological parameters and prognosis were analyzed. Results The median value of BMD was 163.6 Hounsfield units and osteopenia was identified in 103 (53.4%) of the 193 recipients, according to the age-specific formula. In addition to the other tumor burdens, such as tumor numbers ≥5 (HR 2.521, P = 0.027), DCP levels >200 mAU/mL (HR 2.678, P = 0.006), and neutrophil-to-lymphocyte ratio ≥3.01 (HR 2.068, P = 0.025), osteopenia (HR 2.106, P = 0.024) was independent risk factor for mortality by multivariate analysis. Overall survival of the patients who met the two risk factors and more was significantly lower than the others (HR 5.382, P < 0.001). Besides, the calibration plot for the 5-year overall survival using nomogram was predicted very well (C-index 0.746). Conclusions Preoperative osteopenia was independently associated with post-LDLT mortality among patients with HCC. Moreover, risk score and nomogram with calibration curve were developed to confirm the clinical usefulness of osteopenia for post-LDLT patients.