How can we improve prioritization for liver transplantation in patients with hepatocellular carcinoma?

Shorter Height Is Associated With Lower Probability of Liver Transplantation in Patients With Hepatocellular Carcinoma

BACKGROUND

The effect of height and sex on liver transplantation (LT) for hepatocellular carcinoma (HCC) remains unclear.

METHODS

Using United Network for Organ Sharing (UNOS) data, 14 844 HCC patients listed for LT from 2005 to 2015 were identified. Cumulative incidence of waitlist events (LT and dropout for death or too sick) were calculated and modeled using Fine and Gray competing risk regression.

RESULTS

Short (SWR), mid (MWR), and long (LWR) UNOS wait regions comprised 25%, 42%, and 33% of the cohort. Three-year cumulative incidence of LT was lower in shorter height patients (≤150, 151-165, and >185 cm; 70.8%, 76.7%, and 83.5%; P < 0.001) and women (78.2% versus 79.8%; P < 0.001). On multivariable analysis, shorter height (≤150, 151-165 cm, hazard ratio [HR] versus >185 cm) was associated with lower probability of LT (0.81 and 0.89; P = 0.02) and greater dropout (HR 1.99 and 1.43; P < 0.001). Female sex was not associated with LT overall, but a significant sex and wait region interaction (P = 0.006) identified lower LT probability for women in MWR (HR versus men, 0.91; P = 0.02).

CONCLUSIONS

Despite uniform HCC Model for End-Stage Liver Disease exception across height and sex, shorter patients and females in MWR have lower probability of LT. Consideration should be given to awarding additional Model for End-Stage Liver Disease exception points to these patients.

Comparison of two equivalent model for end-stage liver disease scores for hepatocellular carcinoma patients using data from the United Network for Organ Sharing liver transplant waiting list registry

Patients with hepatocellular carcinoma (HCC) have been advantaged on the liver transplant waiting list within the United States, and a 6-month delay and exception point cap have recently been implemented to address this disparity. An alternative approach to prioritization is an HCC-specific scoring model such as the MELD Equivalent (MELD_EQ ) and the mixed new deMELD. Using data on adult patients added to the UNOS waitlist between 30 September 2009 and 30 June 2014, we compared projected dropout and transplant probabilities for patients with HCC under these two models. Both scores matched actual non-HCC dropout in groups with scores <22 and improved equity with non-HCC transplant probabilities overall. However, neither score matched non-HCC dropout accurately for scores of 25-40 and projected dropout increased beyond non-HCC probabilities for scores <16. The main differences between the two scores were as follows: (i) the MELD_EQ assigns 6.85 more points after 6 months on the waitlist and (ii) the deMELD gives greater weight to tumor size and laboratory MELD. Post-transplant survival was lower for patients with scores in the 22-30 range compared with those with scores <16 (P = 0.007, MELD_EQ ; P = 0.015, deMELD). While both scores result in better equity of waitlist outcomes compared with scheduled progression, continued development and calibration is recommended.