We estimated the direct attributable cost of 21 different cancer sites in Belgium, using data collected at national level. Ambulatory visits, including medication costs, appeared to be the highest contributor to the total healthcare expenditure of people with a cancer diagnosis. In 2018, people with a cancer diagnosis had a total direct cost 2.5 times higher than people without cancer. Bronchus and lung cancer, liver cancer, pancreas cancer and mesothelioma were among the sites with the highest direct cost. This might be explained by the relatively low survival and duration of the disease, leading to have in our sample a combination of many “new” cases in 2018, with a higher cost for starting a treatment, and cases in a final stage of cancer in 2018, with higher end-of-life costs. We also investigated the association between average incremental cost attributable to cancer and different covariates that could impact cost of cancer. Costs decreased with the years since diagnosis and increased if cancer was present in more than one site.
Comparing the average cost per case highlights the cancer sites (bronchus and lung cancer, liver cancer, pancreatic cancer and mesothelioma) that are more costly regardless of the number of people that are affected by them. We were also interested in investigating which cancer sites have the highest burden on the total healthcare cost reimbursed by the Belgian public health insurance funds. Bronchus and lung cancer was by far the most costly cancer site, with a cost two times higher than breast and colorectal cancer (respectively the second and third most costly cancer sites at population level). To date, only studies referring to the total cost of cancer (without distinction among cancer site) [3] or studies focusing on the cost of one specific cancer site [13] can be found in the literature. In the Flemish region, the direct cost attributable to breast cancer was estimated to amount to €12,037 per patient over a 6-year period [7]. A study comparing the cost of different cancer sites in the United States showed that the total national expenditures for care of breast cancer was the highest, followed by colorectal, lung and prostate cancer [14], revealing a similar rank to the one of our study.
Our study adopted a prevalence-approach to assess the total economic burden of a cancer site in a specific year. This provides decision makers with a picture of the global burden and the areas where cost containment policies would have the greatest impact [15], which is informative to design cost containment policies. This approach should not be confused with the incidence-approach where lifetime costs are computed for the cases that occur during the defined base incident year, and that are more suitable for measuring the potential savings from preventive interventions [8]. Within our approach, caution is nonetheless warranted when contrasting costs between prevalent cases versus controls [16], [17]. First, under our definition, prevalent cases have survived until 1st January 2018, in spite of their cancer. This may lead to selection bias since the group of cancer cases likely contains fewer people who have poor health for other reasons than their cancer (e.g., lifestyle) than controls. Indeed, such cases are at greater risk of death by 1st January 2018 than similar people in the control group, due to their cancer. Since people with poor health likely also have higher medical costs, such selection bias may have led to underestimation of the attributable costs. This is in the opposite direction of the confounding bias expected as a result of not having matched cases and controls on key lifestyle factors. The data available does not allow to neither include these factors in the analysis nor to quantify the bias derived from them. Second, the comparison of attributable costs between cancer sites is partly influenced by the fact that cases may be in different stages of disease between different cancer sites, as a result of cancer site-specific mortality rates.
Policy actions addressing the burden of cancer and its impacts should be two-fold; firstly, addressing the onset and recovery of cancer in Belgium, and secondly reducing its association with adverse health outcomes (e.g. complications) that result in a higher healthcare use. These policies are needed to target cancer both at individual and a population level, as highlighted by our research. For instance, we showed that the cost of bronchus and lung cancer is the highest and it is one of the most prevalent in Belgium. Mesothelioma resulted to be the cancer with the highest YLD per case rate and among the cancers with the highest cost per case, but the lowest total health and economic burden due to its low prevalence. This highlights the need to look at the problem both from an individual and population perspective. It was also revealed that some cancer sites have a low health burden and healthcare cost per case. In the case of breast and cervical cancer these might be associated to the success of screening measures achieving an early detection and consequentially a lower burden. Cost of current care (which is considered here) represents one element to be considered in cost containment policies. A higher cost can also be associated to a higher cost for innovative treatments resulting in increased survival (and in the long run in a lower disability burden and increased productivity). Ideally it should be taken into account together with other factors: potential and cost/effectiveness of screening, new therapies that become available, etc. In addition, higher costs and higher YLD might correspond to a longer survival of people living with cancer. Higher costs could be caused by new treatments that improved survival and increasing time of disease monitoring.
We would also like to draw the attention to the fact that many of the high ranked cancers are very strongly linked to risk factors such as smoking, alcohol, lack of physical activity, obesity, environmental stressors. This reinforces the message that the best investment for health policy makers to reduce cancer and cancer costs is to take actions to reduce these risk factors at population level.
Strengths and limitations
Our analysis included national claims data collected at population-level and includes inpatient, outpatient healthcare and prescribed medication. Considering that indirect costs are difficult to track and quantify, our analysis focused on the direct cost of cancer. Indirect costs, including loss of productivity and informal caregiving costs, represent an important part of cost for patients with cancer that clearly add up to the total cost of cancer. Some limitations are attributed to the possible failure to control sufficiently for confounding and selection bias. This is due to the limited amount of available data in our data sources. For example, neither BCR nor IMA have indication on lifestyle risk factors and complete information on comorbidities.
Our results should be interpreted as a snapshot of healthcare costs related to cancer in a specific year based on a 10-year prevalence approach rather than lifetime costs of cancer (incidence-based approach).