Lower middle-income countries: A risk factor for lower survival in glioblastoma? Evidence for health care providers

Brain tumors are characterized by high mortality and morbidity and necessitate concentrated resource allocation and aggregated multidisciplinary diagnostic and therapeutic techniques. Moreover, the global burden of central nervous system cancers has increased within the last decades, which makes brain cancers a worldwide challenge to healthcare systems.¹

The hypothesis that brain tumor patients in countries with low socioeconomic status (SES) and less advanced public healthcare systems have poorer outcomes has been elaborated in several studies.^2,3 Studies clearly show that survival is significantly higher among patients with high SES. This inequality is attributable to many factors, such as general access to health systems and access to specialized diagnostic and therapeutic resources. For example, access to radio chemotherapy may be an important factor in healthcare quality and outcomes. However, studies show that in all patients receiving radio-chemotherapy, SES was an independent factor for improved survival in cases of glioma. This implies that access to healthcare may not be the only factor in outcomes and that in patients with lower SES, other factors, such as exposure to environmental or occupational hazards, may play additional roles.² On national and global levels, after comparing high-income versus low- and middle-income countries, a higher incidence of glioma (high- and low-grade) was associated with higher SES.^1,2,4 The explanation for the increased incidence of glioma comprises the same arguments (higher rate of diagnosis and access to screening programs) and is positively associated with access to healthcare. However, when comparing population-based datasets, many confounders must be considered, including ethnicity, urbanity, availability of academic centers, and others.

The population-based study by Artem Rozumenko et al. analyzes for the first time population-based data on treatment compliance and survival outcomes based on data from the National Cancer Registry of Ukraine (2015–2019).⁵ Almost 3000 adult glioblastoma patients were included. The results of this study show that only 19 percent of glioblastoma patients received the standard treatment protocol (surgery followed by radio-chemotherapy), which is considerably low compared to data from high-income countries; where about 50 percent of patients receive the standard treatment protocol. The incorporation of data concerning the number of adjuvant cycles of chemotherapy, unfortunately, is a practical problem in population-based registries. Due to the incompleteness and the lack of reliability of the registry data for adjuvant chemotherapy, referring results are often omitted. However, according to the low proportion of patients receiving standard treatment (surgery followed by radio-chemotherapy), the median overall survival in Ukraine (10.6 months) looks surprisingly good, as population-based data from high-income countries indicates overall survival of 10 to 12 months. One explanation is, that the Ukrainian glioblastoma patients included in the study were younger (median age, 57 years) compared to epidemiological data (median age, 65 years), which clearly undermines the comparison with respect to the overall survival reflected in data sets from high-income countries!

Access to academic facilities also seems to have a positive effect on outcomes, which has been observed in high-income countries and was now confirmed also in the Ukrainian population.^6,7 This result probably reflects the complexity of the management of brain tumor patients and the challenges of diagnostic and therapeutic decision-making.

Today, evidence that the relationship between mortality and incidence, even in glioma patients, is driven by socioeconomic and sociodemographic factors is increasing. In addition to early detection and the implementation of standard diagnostics and treatment, we need more evidence to better understand the role of socioeconomic inequalities in glioblastoma care. Therefore, future studies should investigate the extent to which the allocation of diagnostic and therapeutic resources—in other words, highly specialized medical care and long-term management—contributes to improved or deteriorated outcomes (eg, overall survival). One way of achieving this will be to compare high-quality population-based datasets from different national registries. The Ukrainian register study by Rozumenko et al., therefore, adds important information with respect to data from a lower middle-income country.

Moreover, in order to increase the granularity of survival calculation and prediction in glioblastoma patients, by including clinical, radiological, histological, and molecular data, together with socioeconomic and demographic information, big data science and machine learning algorithms are warranted.^8,9 High-quality national registries play a key role in meeting the goal of identifying disparities in socioeconomic and sociodemographic variables to enable scientists, clinicians, and healthcare providers to intervene on a political level.