Impact of visceral adiposity on outcomes from hepatocellular carcinoma following liver transplantation

      Introduction: Over 50,000,000 Americans are obese. The number of patients with HCC undergoing Orthotopic liver transplant (OLT) is rising. Assessing recipient characteristics, like obesity, that have negative effects on oncologic outcomes is critical to the appropriate allocation of donor livers.
      Body mass index (BMI), a composite measure of subcutaneous and visceral adiposity, has been used as a marker for obesity. However, it is now known that visceral adiposity alone is responsible for the secretion of a protumorogenic systemic-mileu.
      Hypothesis: We hypothesize that visceral adiposity measured by MRI is a prognostic indicator of oncologic outcomes after OLT for HCC and, MRI measures of visceral adiposity correlate with oncologically inferior explant pathology.
      Methods: From January 1999–January 2013 we identified 423 patients with HCC who underwent OLT and had MRI imaging preOLT. Peri-renal fat thickness, a standardized measure of visceral obesity, was calculated on all MRI scans. Demographics and BMI, HCC recurrence, days to recurrence, and survival were measured. All explant pathology was reviewed. Student;s t test, Chi-Square and Kaplan Meier curves were used as appropriate.
      Results: Mean MELD was 22±8. No differences were noted in MELD across spectrum of BMI or peri-renal fat thickness. Total recurrence rate = 12%.
      Peri-renal fat size0-5 mm (n = 19)5-10 mm (n = 38)10-15 mm (n = 72)15-20 mm (n = 46)20-25 mm (n = 34)25-30 mm (n = 24)≥30 mm (n = 21)
      % HCC Recurrence rate07.913.910.914.7*16.7*14.3* (3)
      Time to recurrence (days) (mean)N/A781811588279*172*676 (524)
      %Microvascular Invasion10.521.116.721.723.512.538.1* (8)
      %Lymphovascular Invasion001.408.84.24.8 (1)
      %Poor Differentiated5.27.912.513.023.5*16.723.8* (5)
      *p<0.05 vs perirenal fat thickness <20mm
      [Visceral Adiposity & Outcomes]
      Conclusions: These data show that increasing visceral adiposity is associated with increased recurrence and hastened time to recurrence. Additionally, visceral adiposity is associated with oncologically inferior explant pathology. Therefore, visceral adiposity in patients with HCC should be used as a prognostic marker to determine appropriate allocation of livers in HCC recipients with similar MELD scores.