Surveillance for Hepatocellular Carcinoma Reduces Mortality: an Inverse Probability of Treatment Weighted Analysis

Abstract

Background: Evidence supporting benefit of hepatocellular carcinoma (HCC) surveillance in reducing mortality is not well-established. The effect of HCC surveillance in reducing mortality was assessed by an inverse probability of treatment weighting (IPTW)-based analysis controlled for inherent bias and confounders in observational studies.

Material and methods: This retrospective cohort study was conducted on 446 patients diagnosed with HCC between 2007 and 2013 at a major referral center. Surveillance was defined as having at least 1 ultrasound test within a year before HCC diagnosis. Primary outcome was survival estimated using the Kaplan-Meier method with lead-time bias adjustment and compared using the log-rank test. Hazard ratio (HR) and 95% confidence interval (CI) were computed using conventional Cox and weighted Cox proportional hazards analysis with IPTW adjustment.

Results: Of the 446 patients, 103 (23.1%) were diagnosed with HCC through surveillance. The surveillance group had more patients with the Barcelona-Clinic Liver Cancer stage A (80.6% vs. 33.8%, P < 0.0001), more patients eligible for potentially curative treatment (73.8% vs. 44.9%, P < 0.0001), and longer median survival (49.6 vs. 15.9 months, P < 0.0001). By conventional multivariate Cox analysis, HR (95% CI) of surveillance was 0.63 (0.45-0.87), P = 0.005. The estimated effect of surveillance remained similar in the IPTW-adjusted Cox analysis (HR: 0.57; 95% CI: 0.43-0.76, P < 0.001).

Conclusions: HCC surveillance by ultrasound is associated with a 37% reduction in mortality. Even though surveillance is recommended in all guidelines, but in practice, it is underutilized. Interventions are needed to increase surveillance rate for improving HCC outcome.