IMPROVED SURVIVAL IN PATIENTS WITH VIRAL HEPATITIS-INDUCED HEPATOCELLULAR CARCINOMA UNDERGOING RECOMMENDED ULTRASONOGRAPHIC SURVEILLANCE

Purpose: Hepatocellular carcinoma (HCC) is an increasing public health problem worldwide. Practice guidelines recommend surveillance for high-risk patients to detect HCC at an early stage when curative treatments can be applied to achieve long-term survival benefit. There are, however, limited data on the utilization of recommended HCC surveillance in Canada. We examined the impact of routine ultrasonographic surveillance on mortality in patients diagnosed with viral hepatitis-induced HCC and determined predictors of receiving routine ultrasonographic surveillance utilizing Ontario Cancer Registry linked health administrative data.

Method: We conducted a retrospective cohort study of all eligible viral hepatitis patients who developed HCC over the period 1990-2009. The timing and intensity of HCC surveillance for 2 years before HCC diagnosis were assigned hierarchically as follows: i) ≥2 abdominal ultrasound screens annually; ii) 1 screen annually; iii) inconsistent screening; and iv) no screening. Survival rates were estimated utilizing the Kaplan-Meier method and parametric models to correct for lead time bias. Association between the timing and intensity of HCC surveillance and the risk of mortality after HCC diagnosis was examined utilizing Cox proportional hazards regression models adjusting for sociodemographics, clinical characteristics, index year, and HCC treatment. Log binomial regression models were constructed to determine predictors of receiving >1 ultrasound screening annually for 2 years before HCC diagnosis.

Result: The study cohort comprised 1,443 patients with viral hepatitis-induced HCC. An estimated 12.5% of patients received ≥2 screens annually for 2 years before HCC diagnosis, 33.8% received 1 screen annually, 43.2% received inconsistent screening, and 10.5% did not receive screening. Compared to those not screened, those receiving ≥2 screens or 1 screen annually were significantly associated with a lower mortality risk, corrected for lead time bias (HCC sojourn time 70 days: HR (95% CI): 0.64 (0.48-0.84) and 0.64 (0.51-0.79), respectively; HCC sojourn time 140 days: HR (95% CI): 0.68 (0.52-0.90) and 0.69 (0.55-0.85), respectively). High-risk viral hepatitis patients with cirrhosis or esophageal varices, and those diagnosed in most recent years (2005-2009 vs. 1990-1994) were independently associated with increased odds of receiving routine ultrasonographic surveillance.

Conclusion: Our findings suggest that routine ultrasonography of the liver in patients with viral hepatitis is associated with reduced mortality in a population-based setting. Information about the effectiveness of HCC surveillance is important to inform health policy to improve the healthcare system.