Epidemiology and survival of adult-type diffuse glioma in Belgium during the molecular era

BACKGROUND

Survival data of diffuse adult-type glioma is mostly based on prospective clinical trials or small retrospective cohort studies. Real-world data with large patient cohorts is currently lacking.

METHODS

Using the nationwide, population-based Belgian Cancer Registry, all known histological reports of patients diagnosed with an adult-type diffuse glioma in Belgium between 2017 and 2019 were reviewed. The ICD-O-3 morphology codes were matched with the histological diagnosis. The gathered data were transformed into the 2021 World Health Organization classification of CNS tumors using the IDH- and 1p/19q-mutation status.

RESULTS

Between 2017 and 2019, 2233 diffuse adult-type gliomas were diagnosed in Belgium. Full molecular status was available in 67.1% of identified cases. The age-standardized incidence rate of diffuse adult-type glioma in Belgium was estimated at 8.55 per 100 000 person-years and 6.72 per 100 000 person-years for grade 4 lesions. Median overall survival time in IDH-wild-type glioblastoma was 9.3 months, significantly shorter compared to grade 4 IDH-mutant astrocytoma (median survival time: 25.9 months). The 3-year survival probability was 86.0% and 75.7% for grades 2 and 3 IDH-mutated astrocytoma. IDH-wild-type astrocytoma has a worse prognosis with a 3-year survival probability of 31.6% for grade 2 and 5.7% for grade 3 lesions.

CONCLUSIONS

This registry-based study presents a large cohort of adult-type diffuse glioma with known molecular status and uses real-world survival data. It adds to the current literature which is mainly based on historical landmark trials and smaller retrospective cohort studies.

Long-term health-care utilisation in older patients with cancer and the association with the Geriatric 8 screening tool: a retrospective analysis using linked clinical and population-based data in Belgium

BACKGROUND

Little evidence is available on the long-term health-care utilisation of older patients with cancer and whether this is associated with geriatric screening results. We aimed to evaluate long-term health-care utilisation among older patients after cancer diagnosis and the association with baseline Geriatric 8 (G8) screening results.

METHODS

For this retrospective analysis, we included data from three cohort studies for patients (aged ≥70 years) with a new cancer diagnosis who underwent G8 screening between Oct 19, 2009 and Feb 27, 2015, and who survived more than 3 months after G8 screening. The clinical data were linked to cancer registry and health-care reimbursement data for long-term follow-up. The occurrence of outcomes (inpatient hospital admissions, emergency department visits, use of intensive care, contacts with general practitioner [GP], contacts with a specialist, use of home care, and nursing home admissions) was assessed in the 3 years after G8 screening. We assessed the association between outcomes and baseline G8 score (normal score [>14] or abnormal [≤14]) using adjusted rate ratios (aRRs) calculated from Poisson regression and using cumulative incidence calculated as a time-to-event analysis with the Kaplan-Meier method.

FINDINGS

7556 patients had a new cancer diagnosis, of whom 6391 patients (median age 77 years [IQR 74-82]) met inclusion criteria and were included. 4110 (64·3%) of 6391 patients had an abnormal baseline G8 score (≤14 of 17 points). In the first 3 months after G8 screening, health-care utilisation peaked and then decreased over time, with the exception of GP contacts and home care days, which remained high throughout the 3-year follow-up period. Compared with patients with a normal baseline G8 score, patients with an abnormal baseline G8 score had more hospital admissions (aRR 1·20 [95% CI 1·15-1·25]; p<0·0001), hospital days (1·66 [1·64-1·68]; p<0·0001), emergency department visits (1·42 [1·34-1·52]; p<0·0001), intensive care days (1·49 [1·39-1·60]; p<0·0001), general practitioner contacts (1·19 [1·17-1·20]; p<0·0001), home care days (1·59 [1·58-1·60]; p<0·0001), and nursing home admissions (16·7% vs 3·1%; p<0·0001) in the 3-year follow-up period. At 3 years, of the 2281 patients with a normal baseline G8 score, 1421 (62·3%) continued to live at home independently and 503 (22·0%) had died. Of the 4110 patients with an abnormal baseline G8 score, 1057 (25·7%) continued to live at home independently and 2191 (53·3%) had died.

INTERPRETATION

An abnormal G8 score at cancer diagnosis was associated with increased health-care utilisation in the subsequent 3 years among patients who survived longer than 3 months.

FUNDING

Stand up to Cancer, the Flemish Cancer Society.

End-of-Life Care in the Last Three Months before Death in Older Patients with Cancer in Belgium: A Large Retrospective Cohort Study Using Data Linkage

This study aims to describe end-of-life (EOL) care in older patients with cancer and investigate the association between geriatric assessment (GA) results and specialized palliative care (SPC) use. Older patients with a new cancer diagnosis (2009-2015) originally included in a previous multicentric study were selected if they died before the end of follow-up (2019). At the time of cancer diagnosis, patients underwent geriatric screening with Geriatric 8 (G8) followed by GA in case of a G8 score ≤14/17. These data were linked to the cancer registry and healthcare reimbursement data for follow-up. EOL care was assessed in the last three months before death, and associations were analyzed using logistic regression. A total of 3546 deceased older patients with cancer with a median age of 79 years at diagnosis were included. Breast, colon, and lung cancer were the most common diagnoses. In the last three months of life, 76.3% were hospitalized, 49.1% had an emergency department visit, and 43.5% received SPC. In total, 55.0% died in the hospital (38.5% in a non-palliative care unit and 16.4% in a palliative care unit). In multivariable analyses, functional and cognitive impairment at cancer diagnosis was associated with less SPC. Further research on optimizing EOL healthcare utilization and broadening access to SPC is needed.

Patterns of care and survival for lung cancer: Results of the European population-based high-resolution study

Objectives

To investigate differences in lung cancer (LC) management and survival using data from European population cancer registries.

Methods

We analysed 4,602 lung cancer cases diagnosed in 2010-2013, followed-up to 2019 in five countries. Multivariable logistic regression was used to calculate the Odds Ratio (OR) of surgery for stages I-II LC or chemo- or radiotherapy for stages III-IV LC. Relative survival (RS) was estimated by the actuarial method; Relative Excess Risk of death (RER), with 95% CI, was calculated by generalized linear models.

Results

Diagnostic work-up was extensive for 65.9% patients (range 57%, Estonia, Portugal - 85% (Belgium). Sixty-six percent of stages I-II patients underwent surgery; compared to non-operated, their adjusted OR decreased with age and was associated with main bronchus cancer (OR vs. lobes 0.25, CI, 0.08-0.82), stage II (OR vs. stage I: 0.42, CI, 0.29-0.60), comorbidity (OR vs. absent: 0.55, CI, 0.33-0.93), country (ORs: Estonia 1.82, CI, 1.28-2.60; Belgium 0.62, CI, 0.42-0.91; Portugal 0.69, CI, 0.52-0.93).Almost half of stages III-IV patients received chemo- or radiotherapy only; the adjusted OR vs. non receiving decreased with age and was associated with unspecified cancer topography or morphology. The adjusted five-year RER increased with age and stage and was lower for women (0.78, CI, 0.72-0.86), above the reference for main bronchus cancer (1.37, CI, 1.21-1.54) and unspecified morphology (1.17, CI, 1.05-1.30). Surgery carried the lowest mortality (RS 56.9; RER 0.13, CI, 0.11-0.15) with RER above the mean in Estonia (1.20, CI, 1.10-1.30), below it in Portugal (0.88, CI, 0.82-0.93) and Switzerland (0.91, CI, 0.84-0.99). Comorbidity (1.21, CI, 1.09-1.35) and not smoking (0.68, CI, 0.57-0.81) were associated with RER.

Conclusions

The survival benefit of early diagnosis, allowing curative surgery, was evident at the population level. Screening for subjects at risk and adhesion to standard care should be incremented across the EU by funding better equipment and training health personnel.

Linking clinical and population-based data in older patients with cancer in Belgium: Feasibility and clinical outcomes

INTRODUCTION

Geriatric screening and geriatric assessment (GS/GA) have proven their benefits in the care for older patients with cancer. However, less is known about the predictive value of GS/GA for outcomes. To research this, clinical data on GS/GA can be enriched with population-based data. In this article we describe the methods and feasibility of data linkage, and first clinical outcomes (GS/GA results and overall survival).

MATERIALS AND METHODS

A large cohort study consisting of patients aged ≥70 years with a new cancer diagnosis was established using linked data from clinical and population-based databases. Clinical data were derived from a previous prospective study where older patients with cancer were screened with G8, followed by GA in case of an abnormal result (GS/GA study; 2009-2015). These data were linked to cancer registration data from the Belgian Cancer Registry (BCR), reimbursement data of the health insurance companies (InterMutualistic Agency, IMA), and hospital discharge data (Technical Cell, TCT). Cox regression analyses were conducted to evaluate the prognostic value of the G8 geriatric screening tool.

RESULTS

Of the 8067 eligible patients with a new cancer diagnosis, linkage of data from the GS/GA study and data from the BCR was successful for 93.7%, resulting in a cohort of 7556 patients available for the current analysis. Further linkage with the IMA and TCT database resulted in a cohort of 7314 patients (96.8%). Based on G8 geriatric screening, 67.9% of the patients had a geriatric risk profile. Malnutrition and functional dependence were the most common GA-identified risk factors. An abnormal baseline G8 score (≤14/17) was associated with lower overall survival (adjusted HR [aHR] = 1.62 [1.50-1.75], p < 0.001).

DISCUSSION

Linking clinical and population-based databases for older patients with cancer has shown to be feasible. The GS/GA results at cancer diagnosis demonstrate the vulnerability of this population and the G8 score showed prognostic value for overall survival. The established cohort of almost 8000 patients with long-term follow-up will serve as a basis in the future for detailed analyses on long-term outcomes beyond survival.

Cancer Registration, Molecular Marker Status, and Adherence to the WHO 2016 Classification of Pathology Reports for Glioma Diagnosed during 2017-2019 in Belgium

INTRODUCTION

The objective of this study was to cross-check and, if necessary, adjust registered ICD-O-3 topography and morphology codes with the findings in pathology reports available at the Belgian Cancer Registry (BCR) for glioma patients. Additionally, integration of molecular markers in the pathological diagnosis and concordance with WHO 2016 classification is investigated.

METHODS

Since information regarding molecular tests and corresponding conclusions are not available as structured data at population level, a manual screening of all pseudonymized pathology reports available at the BCR for registered glioma patients (2017-2019) was conducted. ICD-O-3 morphology and topography codes from the BCR database (based on information as provided by hospital oncological care programmes and pathology laboratories), were, at tumour level, cross-checked with the data from the pathology reports and, if needed, specified or corrected. Relevant molecular markers (IDH1/2, 1p19q codeletion, promoter region of the MGMT gene [MGMTp]) were manually extracted from the pathology reports.

RESULTS

In 95.3% of gliomas, the ICD-O-3 morphology code was correct. Non-specific topography codes were specified in 9.3%, while 3.3% of specific codes were corrected. The IDH status was known in 75.2% of astrocytic tumours. The rate of correct integrated diagnoses varied from 47.6% to 56.4% among different gliomas. MGMTp methylation status was available in 32.2% of glioblastomas.

CONCLUSION

Both the integration of molecular markers in the conclusion of the pathology reports and the delivery of those reports to the BCR can be improved. The availability of distinct ICD-O-3 codes for each molecularly defined tumour entity within the WHO classification would increase the consistency of cancer registration, facilitate population level research and international benchmarking.

P11.28.A Cancer registration and adherence to the WHO 2016 classification of pathology reports for astrocytic tumors in Belgium from 2017 to 2019

Background

The objective of this study is to cross-check the ICD-O-3 topography and morphology codes of registered glioma patients with findings in their pathology reports and to investigate the integration of relevant molecular markers in the final histopathological diagnosis.

Materials and methods

Since information regarding molecular tests and corresponding conclusions are not available as structured data at the Belgian population level a manual screening of all pseudonymized full text pathology reports available at the Belgian Cancer Registry (BCR) for adult glioma patients diagnosed between 2017 and 2019 was conducted. ICD-O-3 morphology and topography codes from the BCR database (provided by the hospital oncological care programs and laboratories for histopathology), were cross-checked with the data from the pathology reports. Relevant molecular markers were manually extracted from the pathology reports of confirmed glial tumors. The final diagnosis as mentioned in the reports and the integration of the appropriate molecular markers were checked against the WHO 2016 classification.

Results

For 1.892 of 2.379 registered gliomas (73%), a specific topographic code was provided. For 8% of patients registered with code C71.9 (unspecified region of the brain), a change to a specific topography code was implemented based on details in the pathology reports. For only 98 of 2.186 patients (4,5%) with available pathology reports, the ICD-O-3 morphology code was adjusted based on the information in the pathology reports. For 59 patients this was a change of grade within the same tumor group. In the subgroup of patients with astrocytic tumors, for 314 of 1.887 patients (16,6%) the IDH status (IDH1-IHC or IDH1/2-NGS) was not identifiable in the available reports. For only 1.091 of 1.887 patients (57,8%) the reports provided an integrated diagnosis including molecular findings, while for the other reports the tumor was not specified (NOS) in the conclusion. For 1.309 of 1.887 patients (69,4%), the final diagnosis in the pathology reports was compatible with the molecular markers. For 553 (29%) patients this was not the case because the relevant molecular markers were not integrated in the conclusion although available (i.e. in the conclusion of these pathology reports the tumor was NOS, but details of the molecular test result were however available somewhere in the reports).

Conclusion

Morphology codes of registered glioma are largely in line with findings in the pathology reports. The use of specific ICD-O-3 topography codes should be further encouraged and also molecular testing and the use of the integrated diagnosis in the pathology reports can be improved. These findings will be further processed and incorporated in the ongoing Quality Indicator project for glioma in Belgium and will be used to develop strategies to further optimize the reporting of these tumors towards the BCR.

General practitioner contacts, hospitalizations, and nursing home transfers in older patients up to three years after new cancer diagnosis: Results from a large data linkage cohort study

12041

Background: Long-term outcomes after cancer diagnosis in older persons are largely unexplored because of limited follow-up in clinical studies. By linking clinical data with population-based data, studying long-term outcomes in large cohorts becomes feasible. The current study aims to explore long-term outcomes in the care trajectory of older patients with cancer and to assess their association with baseline geriatric screening and assessment (GS/GA) results. Methods: A large cohort study of older patients with a new cancer diagnosis was set up by linking clinical, cancer registry and administrative health data based on a unique patient identifier. Clinical data were derived from a previously performed prospective multicentric Belgian study (2009-2015). Patients aged ≥ 70 years were screened with G8 followed by GA in case of an abnormal result (≤14/17). Tumor characteristics and vital status were derived from cancer registry data and long-term outcomes (general practitioner (GP) contacts, hospitalizations and nursing home transfers) from administrative health data. In patients that survived at least 3 months since inclusion, outcomes were assessed from the day after inclusion until 3 years after. Event rates were calculated using person-time at risk to allow for varying follow-up time. Patients were censored 3 months before death to exclude influence of end-of-life care. Results: After data linkage, 6,391 older patients with a new cancer diagnosis were available for this analysis. The median age was 77 (range: 70–100) and 59.8% was female. Diagnoses included solid (92.8%) and hematologic malignancies (7.2%). In the patients with a solid tumor, breast, colorectal and lung cancer were the most common and 20.1% of patients had stage IV. 64.3% of patients had an abnormal baseline G8 score. During the 3 year follow-up, 2,602 (40.7%) of the included patients died. In these 3 years, 5,985 (95.2%) patients had at least one contact with a GP and 4,634 (72.5%) had at least one new hospital admission (event rates in Table 1). Of the 3,724 patients living independently at inclusion and still alive after 3 years, 281 (7.5%) had been transferred to a nursing home and of those, 240 (85.4%) patients had an abnormal baseline G8 score. Conclusions: Older patients with an abnormal baseline G8 score have more GP contacts, hospital admissions and nursing home transfers in the 3 years following a new cancer diagnosis compared to patients with normal baseline G8 score. Baseline G8 could help identify patients at risk for higher long-term healthcare utilization.[Table: see text]

External Validation of the Dutch SOURCE Survival Prediction Model in Belgian Metastatic Oesophageal and Gastric Cancer Patients

The SOURCE prediction model predicts individualised survival conditional on various treatments for patients with metastatic oesophageal or gastric cancer. The aim of this study was to validate SOURCE in an external cohort from the Belgian Cancer Registry. Data of Belgian patients diagnosed with metastatic disease between 2004 and 2014 were extracted (n = 4097). Model calibration and discrimination (c-indices) were determined. A total of 2514 patients with oesophageal cancer and 1583 patients with gastric cancer with a median survival of 7.7 and 5.4 months, respectively, were included. The oesophageal cancer model showed poor calibration (intercept: 0.30, slope: 0.42) with an absolute mean prediction error of 14.6%. The mean difference between predicted and observed survival was −2.6%. The concordance index (c-index) of the oesophageal model was 0.64. The gastric cancer model showed good calibration (intercept: 0.02, slope: 0.91) with an absolute mean prediction error of 2.5%. The mean difference between predicted and observed survival was 2.0%. The c-index of the gastric cancer model was 0.66. The SOURCE gastric cancer model was well calibrated and had a similar performance in the Belgian cohort compared with the Dutch internal validation. However, the oesophageal cancer model had not. Our findings underscore the importance of evaluating the performance of prediction models in other populations.

Comorbidities, timing of treatments, and chemotherapy use influence outcomes in stage III colon cancer: A population-based European study

INTRODUCTION

For stage III colon cancer (CC), surgery followed by chemotherapy is the main curative approach, although optimum times between diagnosis and surgery, and surgery and chemotherapy, have not been established.

MATERIALS AND METHODS

We analysed a population-based sample of 1912 stage III CC cases diagnosed in eight European countries in 2009-2013 aiming to estimate: (i) odds of receiving postoperative chemotherapy, overall and within eight weeks of surgery; (ii) risks of death/relapse, according to treatment, Charlson Comorbidity Index, time from diagnosis to surgery for emergency and elective cases, and time from surgery to chemotherapy; and (iii) time-trends in chemotherapy use.

RESULTS

Overall, 97% of cases received surgery and 65% postoperative chemotherapy, with 71% of these receiving chemotherapy within eight weeks of surgery. Risks of death and relapse were higher for cases starting chemotherapy with delay, but better than for cases not given chemotherapy. Fewer patients with high comorbidities received chemotherapy than those with low (P < 0.001). Chemotherapy timing did not vary (P = 0.250) between high and low comorbidity cases. Electively-operated cases with low comorbidities received surgery more promptly than high comorbidity cases. Risks of death and relapse were lower for elective cases given surgery after four weeks than cases given surgery within a week. High comorbidities were always independently associated with poorer outcomes. Chemotherapy use increased over time.

CONCLUSIONS

Our data indicate that promptly-administered postoperative chemotherapy maximizes its benefit, and that careful assessment of comorbidities is important before treatment. The survival benefit associated with slightly delayed elective surgery deserves further investigation.

Comorbidity in head and neck cancer: Is it associated with therapeutic delay, post-treatment mortality and survival in a population-based study?

OBJECTIVES

This study aims to investigate the relationship between comorbidities and therapeutic delay, post-treatment mortality, overall and relative survival in patients diagnosed with squamous cell carcinoma of the head and neck (HNSCC).

PATIENTS AND METHODS

9245 patients with a single HNSCC diagnosed between 2009 and 2014 were identified in the Belgian Cancer Registry. The Charlson Comorbidity Index (CCI) was calculated for 8812 patients (95.3%), distinguishing patients having none (0), mild (1-2), moderate (3-4) or severe comorbidity (>4). The relationship between CCI and therapeutic delay was evaluated using the Spearman correlation. Post-treatment mortality was modelled with logistic regression, using death within 30 days as the event. The association between comorbidity and survival was assessed using Cox proportional hazard models.

RESULTS

Among 8812 patients with a known CCI, 39.2% had at least one comorbidity. Therapeutic delay increased from 31 to 36 days when the CCI worsened from 0 to 4 (rho = 0.087). After case-mix adjustment, higher baseline comorbidity was associated with increased post-surgery mortality (mild, OR 3.52 [95% CI 1.91-6.49]; severe, OR 18.71 [95% CI 6.85-51.12]) and post-radiotherapy mortality (mild, OR 2.23 [95% CI 1.56-3.19]; severe, OR 9.33 [95% CI 4.83-18.01]) and with reduced overall survival (mild, HR 1.39, [95% CI 1.31-1.48]; severe, HR 2.41 [95% CI 2.00-2.90]). That was also the case for relative survival in unadjusted analyses (mild, EHR 1.77 [95% CI 1.64-1.92]; severe, EHR = 4.15 [95% CI 3.43-5.02]).

CONCLUSION

Comorbidity is significantly related to therapeutic delay, post-treatment mortality, 5-year overall and relative survival in HNSCC patients. Therapeutic decision support tools should optimally integrate comorbidity.

Enhanced Biosensor Platforms for Detecting the Atherosclerotic Biomarker VCAM1 Based on Bioconjugation with Uniformly Oriented VCAM1-Targeting Nanobodies

Surface bioconjugation of biomolecules has gained enormous attention for developing advanced biomaterials including biosensors. While conventional immobilization (by physisorption or covalent couplings using the functional groups of the endogenous amino acids) usually results in surfaces with low activity, reproducibility and reusability, the application of methods that allow for a covalent and uniformly oriented coupling can circumvent these limitations. In this study, the nanobody targeting Vascular Cell Adhesion Molecule-1 (NbVCAM1), an atherosclerotic biomarker, is engineered with a C-terminal alkyne function via Expressed Protein Ligation (EPL). Conjugation of this nanobody to azidified silicon wafers and Biacore™ C1 sensor chips is achieved via Copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC) “click” chemistry to detect VCAM1 binding via ellipsometry and surface plasmon resonance (SPR), respectively. The resulting surfaces, covered with uniformly oriented nanobodies, clearly show an increased antigen binding affinity, sensitivity, detection limit, quantitation limit and reusability as compared to surfaces prepared by random conjugation. These findings demonstrate the added value of a combined EPL and CuAAC approach as it results in strong control over the surface orientation of the nanobodies and an improved detecting power of their targets—a must for the development of advanced miniaturized, multi-biomarker biosensor platforms.

Aptamers targeting different functional groups of 17β-estradiol

Aptamers, short synthetic ssDNA or RNA molecules with a specific three-dimensional structure, are promising recognition elements in biosensor technology. In vitro generation of aptamers with high sensitivity and specificity toward a broad range of analytes has been achieved using the systematic evolution of ligands by exponential enrichment (SELEX) process. This iterative pathway of aptamer generation consists of sequential positive and counterselection steps. The present research aimed to select two sets of ssDNA aptamers which both are able to bind to different functional groups on the cyclopentanoperhydrophenanthrene ring of 17β-estradiol (E2). By repetitively switching between positive selection steps using E2 as target molecule and counterselection steps with nortestosterone as countermolecule, aptamers were successfully selected against the hydroxylated aromatic A ring of E2. Additionally, an aptamer which binds the upper segments of the B, C and D ring of the cyclopentanoperhydrophenanthrene ring of E2 was generated after repetitively swapping between positive selection steps with E2 as target molecule and counterselection steps with dexamethasone as countermolecule. Epitope specificity of the aptamers was demonstrated by evaluating their binding responses toward a number of steroid hormones structurally related to E2. The selected aptamers with affinities for different functional groups of E2 can potentially be applied to develop a cross-reactive aptasensor. This aptasensor introduces a promising tool for the future of in-field real-time monitoring of a wide range of steroid hormones.

reMelting curve analysis as a tool for enrichment monitoring in the SELEX process

Current aptamer selection procedures enable limited control and transparency on how the DNA selection pool is evolving. Affinity tests and binding analyses are not always informative. Here we show that real-time PCR provides a valuable tool for the follow-up of aptamer selection. Limited time, work and amount of amplified ssDNA make this an interesting instrument to set-up a SELEX design and monitor the enrichment of oligonucleotides. reMelting Curve Analysis (rMCA) after reannealing under stringent conditions provides information about enrichment, compared to a random library. Monitoring the SELEX process and optimising conditions by means of the proposed methods can increase the selection efficiency in a controlled way. rMCA is applied in enrichment simulations and three different selection procedures. Our results imply that rMCA can be used for different SELEX designs and different targets. SELEX pool diversity analysis by rMCA has been proven to be a useful, reproducible tool to detect and evaluate enrichment of specific binding aptamers while the selection procedure is being performed.