A Weighted Genetic Risk Score of Adult Glioma Susceptibility Loci Associated with Pediatric Brain Tumor Risk

Heritability of nervous system tumors: a sibling-based design

Background

The contribution of genetic and environmental factors to susceptibility to nervous system tumors remains unclear. We performed a quantitative genetic study using a sibling design to estimate the heritability of nervous system tumors, as well as the proportion of the risk of these tumors, which is attributable to environmental factors.

Methods

We conducted a population-based cohort study using Swedish National Register data. All individuals born in Sweden during 1950-2010 with available information on both biological parents were included. A Multi-Generation Register was used to identify family clusters, including both full- and half-siblings. Initially, one index person was randomly selected from each cluster containing only full siblings and one sibling was randomly assigned to this index person. Subsequently, within each of the remaining clusters of full- and half-siblings, an index person was randomly selected, and a half-sibling was randomly assigned to this index person. Among the randomly selected siblings, cases of nervous system tumors were identified using the cancer registry. Quantitative genetic models were used to estimate the proportion of the variance in nervous system tumors attributable to additive genetic factors, shared environment, and individual-specific environment.

Results

The heritability of nervous system tumors was estimated to be 29% (95% confidence interval (CI) = 19%-39%), while the contribution of the non-shared environment to the variance of nervous system tumors was estimated to be 71% (95% CI = 61%-81%). The shared environmental parameter was estimated as zero in the full model.

Conclusion

The variation in susceptibility to nervous system tumors is predominantly attributable to non-shared environmental factors, followed by genetic factors.

Assessing the quality of deliberative stakeholder consultations involving allied health professionals in pediatric palliative care and hematology/oncology in Canada

Background

In this paper we assess the quality of six deliberative stakeholder consultations regarding the implementation of a precision diagnostic for life-threatening pediatric brain tumors. Decision makers who base policy recommendations on the outputs of consultative exercises can presuppose that all deliberants are well informed of the policy issue, that participation in the deliberative process was fair, and that overcoming implementation barriers will necessarily result in practice change. Additional evidence is therefore needed to substantiate the informational quality of the deliberation, measure the equality of participation and study the effects on stakeholder reasoning to appropriately guide uptake of proposed recommendation(s).

Methods

Using the DeVries framework for assessing the deliberative quality, we analyzed data from 44 post-consultation evaluation surveys completed by pediatric oncology and palliative care teams at two tertiary pediatric healthcare centers in Canada. We also conducted turn-taking and word-contribution analyses from the text transcriptions of each deliberation to assess equality of participation using descriptive statistics.

Results

Deliberants agreed the quality of the deliberative process was fair (median ratings ranging from 9–10 out of 10) and the opportunities to receive expert information and discuss with others about the implementation of a new LDT were helpful (9.5 out of 10). While the session improved understanding of the implementation barriers and opportunities, it had marginal effects on deliberants’ reasoning about whether LDTs would change their own clinical practice (3–10 out of 10). Participation was proportionate in at least four of the six deliberations, where no deliberant took more than 20% of total turns and contributed equal to, or less than 20% of total words.

Conclusion

The quality assessment we performed demonstrates high informational value and perceived fairness of two deliberative stakeholder consultations involving pediatric palliative care and oncology teams in Canada. Quality assessments can reveal how the process of deliberation unfolds, whether deliberative outputs are the result of equitable participation among deliberants and what, if any, stakeholder voices may be missing. Such assessments should be routinely reported as a condition of methodological rigor and trustworthiness of deliberative stakeholder engagement research.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12904-021-00884-2.

Pediatric Brain Tumors: Descriptive Epidemiology, Risk Factors, and Future Directions

Brain tumors are the most common solid tumors in children and remain a significant contributor to death by disease in this population. Pediatric brain tumors (PBT) are broadly classified into two major categories: glial and neuronal tumors. Various factors, including tumor histology, tumor location, and demographics, influence the incidence and prognosis of this heterogeneous group of neoplasms. Numerous epidemiologic studies have been conducted to identify genetic and environmental risk factors for these malignancies. Thus far, the only established risk factors for PBTs are exposure to ionizing radiation and some rare genetic syndromes. However, relatively consistent evidence of positive associations for birth defects, markers of fetal growth, advanced parental age, maternal dietary N-nitroso compounds, and exposure to pesticides have been reported. The genetic variants associated with susceptibility to PBTs were predominantly identified by a candidate-gene approach. The identified genetic variants belong to four main pathways, including xenobiotic detoxification, inflammation, DNA repair, and cell-cycle regulation. Conducting large and multi-institutional studies is warranted to systematically detect genetic and environmental risk factors for different histologic subtypes of PBTs. This, in turn, might lead to a better understanding of etiology of PBTs and eventually developing risk prediction models to prevent these clinically significate malignancies.