Targeting population groups with heavier burden of hepatocellular carcinoma incidence: a nationwide descriptive epidemiological study in Sweden

Global epidemiology of liver cancer 2022: An emphasis on geographic disparities

BACKGROUND

Liver cancer remains the sixth most commonly diagnosed cancer and the third leading cause of cancer-related deaths worldwide, causing a heavy burden globally. An updated assessment of the global epidemiology of the liver cancer burden that addresses geographical disparities is necessary to better understand and promote healthcare delivery.

METHODS

Data were extracted from the GLOBOCAN 2022 database, including the number, crude, and age-standardized rates of incidence and mortality at the global, country, continent, and human development index (HDI) regional levels. Age-standardized rates (incidence and mortality) per 100,000 person-years were adjusted based on the Segi-Doll World standard population. The mortality-to-incidence ratios (MIR) for each region and country were calculated. The HDI and gross national income (GNI) for 2022 were obtained, and a Pearson correlation analysis was conducted with the incidence, mortality, and MIR.

RESULTS

In 2022, approximately 866,136 new liver cancer cases and 758,725 related deaths were recorded worldwide, with a global MIR of 0.86. Males had a disproportionately higher burden than females across all levels, and the highest burden was observed in the elderly population. Geographically, the regions with the highest incidence rates included Micronesia, Eastern Asia, and Northern Africa, and the regions with the highest mortality rates included Northern Africa, Southeastern Asia, Eastern Asia, and Micronesia. Notably, Mongolia had a strikingly high burden compared to other countries. The highest MIR was observed in North America and the lowest in Africa. Negative associations of HDI and GNI with liver cancer mortality and MIR were identified, irrespective of sex.

CONCLUSIONS

The current liver cancer burden underscores the presence of remarkable geographic heterogeneity, which is particularly evident across countries with varying HDI levels, highlighting the urgent need to prioritize health accessibility and availability to achieve health inequities.

Lifestyle and genetic risk of chronic liver disease in metabolically healthy and unhealthy individuals from the general population

Background & Aims

It is unclear to what extent lifestyle and genetic factors affect the incidence of chronic liver disease (CLD) in the general population and if lifestyle affects CLD independently of underlying cardiometabolic perturbations and genetic predisposition.

Methods

We examined 27,991 men and women aged 44-73 years from the Malmö Diet and Cancer Study recruited between 1991-1996 and followed until the end of 2020 using registry linkage (median follow-up time 25.1 years; 382 incident first-time CLD events). Associations between cardiometabolic factors, polygenic risk scores (PRSs), and lifestyle factors in relation to CLD were examined using multivariable Cox proportional hazards regression models.

Results

The incidence of CLD increased with number of cardiometabolic risk factors (the hazard ratio per each additional cardiometabolic risk factor was 1.33; 95% CI 1.21-1.45; p = 5.1 x 10-10). Two novel PRSs for metabolic dysfunction-associated steatotic liver disease and a PRS for cirrhosis were associated with higher risk of CLD but provided marginal predictive utility on top of other risk factors and compared to the PNPLA3 rs738409 genetic variant. An unhealthy lifestyle (high alcohol intake, current smoking, physical inactivity and unhealthy diet) markedly increased the risk of CLD (hazard ratio 3.97, 95% CI 2.59-6.10). Observed associations between examined lifestyle factors and CLD were largely independent of cardiometabolic perturbations and polygenic risk.

Conclusions

We confirmed the importance of cardiometabolic dysfunction in relation to risk of CLD in the general population. Lifestyle risk factors were shown to be independently associated with CLD and added predictive information on top of cardiometabolic risk factors. Information on the polygenic risk of liver disease does not currently improve the prediction of CLD in the general population.

Impact and implications

This large population-based prospective study suggests largely independent roles of cardiometabolic, lifestyle, and genetic risk factors in the development of chronic liver disease. Findings strengthen the evidence base for a beneficial effect of modification of high-risk lifestyle behaviors in the primary prevention of chronic liver disease in the general population.

Metabolic dysfunction-associated steatotic liver disease has become the most common cause of hepatocellular carcinoma in Sweden: A nationwide cohort study

Metabolic dysfunction-associated steatotic liver disease (MASLD) is the most prevalent chronic liver disease globally, and can lead to hepatocellular carcinoma (HCC), a leading cause of cancer-related death. We aimed to determine the extent to which MASLD is an increasing cause of HCC in Sweden and to determine clinical characteristics associated with underlying MASLD. Using the Swedish quality registry for liver cancer (SweLiv), we identified all adults with a diagnosis of HCC in Sweden between 2012 and 2018. Baseline data were retrieved from SweLiv and other nationwide registers. Totally, 3494 patients with HCC were identified. Of them, 757 patients (22%) had MASLD-HCC. The proportion with MASLD-HCC increased from 19% in 2012 to 25% in 2018 (ptrend = 0.012), and MASLD was since 2017 the leading cause of HCC, surpassing hepatitis C. MASLD was the fastest growing cause of HCC with a 33% increment during the study period. Compared to other patients with HCC, those with MASLD-HCC were older (75 vs. 67 years, p < .001), less commonly had cirrhosis (61% vs. 82%, p < .001), had larger tumours (median 5.5 vs. 4.3 cm, p < .001), and more often extrahepatic metastasis (22% vs. 16%, p < .001). Patients with HCC caused by MASLD or by other causes were equally likely to be diagnosed in an early stage (Barcelona Clinic Liver Cancer 0-A, 27% vs. 30%, p = .129). MASLD is now the leading cause of HCC in Sweden.

Inequities in primary liver cancer in Europe: The state of play

Given the increasing burden of liver cancer in Europe, it is crucial to investigate how social determinants of health (SDoH) affect liver cancer risk factors and access to care in order to improve health outcomes equitably. This paper summarises the available evidence on the differential distribution of liver cancer risk factors, incidence, and health outcomes in the European Economic Area and the United Kingdom from an SDoH perspective. Vulnerable and marginalised populations have low socio-economic and educational levels and are the most affected by liver cancer risk factors. Reasons for this include varied access to hepatitis B virus vaccination and limited access to viral hepatitis B and C screening, harm reduction, and treatment. Additionally, alcohol-related liver disease remains highly prevalent among individuals with low education, insecure employment, economic instability, migrants, and deprived populations. Moreover, significant variation exists across Europe in the proportion of adults with steatotic liver disease, overweight/obesity, and diabetes, based on geographical area, gender, socio-economic and educational background, and density of ultra-processed food outlets. Inequities in cirrhosis mortality rates have been reported, with the highest death rates among individuals living in socio-economically disadvantaged areas and those with lower educational levels. Furthermore, insufficient healthcare access for key populations with primary liver cancer is influenced by complex healthcare systems, stigmatisation, discrimination, low education, language barriers, and fear of disclosure. These challenges contribute to inequities in liver cancer care pathways. Future studies are needed to explore the different SDoH-interlinked effects on liver cancer incidence and outcomes in European countries. The ultimate goal is to develop evidence-based multilevel public health interventions that reduce the SDoH impact in precipitating and perpetuating the disproportionate burden of liver cancer in specific populations.

Unrecognized liver cirrhosis is common and associated with worse survival in hepatocellular carcinoma: A nationwide cohort study of 3473 patients

BACKGROUND

Data on unrecognized liver cirrhosis in patients with hepatocellular carcinoma (HCC) are derived mainly from cohorts with a risk of selection bias.

OBJECTIVES

In a population-based cohort study we aimed to determine the proportion, characteristics, and prognosis of HCC in patients with unrecognized cirrhosis.

METHODS

Using the Swedish quality register for liver cancer and other nationwide registers, we identified all adults with HCC in Sweden between 2012 and 2018 (n = 3,473).

RESULTS

The final study cohort comprised 2670 patients with established cirrhosis, of which 1033 (39%) had unrecognized cirrhosis at HCC diagnosis. These patients were more often male, older, and had larger tumors, multinodular cancer, portal vein thrombosis, and extrahepatic metastasis compared to patients with known cirrhosis with HCC and under surveillance (34%). Compared to surveilled patients, those with unrecognized cirrhosis had worse median survival (0.89 years, 95% confidence interval [CI] = 0.78-1.01 vs. 3.79 years, 95%CI = 3.19-4.39), and an adjusted hazard ratio of 2.36 (95%CI = 2.09-2.66). Patients with cirrhosis but not under surveillance (27%) and patients with unrecognized cirrhosis had similar characteristics, such as equal proportions diagnosed at late stage (79%).

CONCLUSIONS

Cirrhosis is often not recognized in patients with HCC. Unrecognized cirrhosis is associated with more advanced HCC at diagnosis and a worse prognosis. More efforts are needed to diagnose cirrhosis at an earlier stage.