Background:Population-based cancer registries aim for timely reporting of cancer incidence and rapid identification of unexpected patterns to support cancer control. To facilitate large-scale, systematic, first evaluation of incidence data, a semi-automated tool was built that flags statistically significant deviations from historical trends, which may merit further investigation. Materials and methods:The tool was developed in the open-source programming language R and uses a CSV file to specify input parameters. For each row, observed or age-standardised incidence rates are calculated, and corresponding graphical outputs, with various stratifications and substratifications, are produced. A flexible regression model is fitted to all but the most recent incidence year, with an automated algorithm determining optimal knotpoint placement. The model is then extrapolated to estimate the expected incidence for the final year, which is statistically compared with the observed value. The model is visually represented, including confidence bands, in the graphical output. Results are exported as PNG files organised in hierarchical folders, along with a structured Quarto HTML report containing all figures. Results:The modelling approach captured complex temporal patterns without overfitting and reliably identified deviations from historical trends. This high-throughput tool is highly customisable and can be extended to analyse stage-specific incidence trends or stratifications by other categorical variables. Conclusions:This semi-automated tool enables efficient first-line visual evaluation of newly available registry data to highlight emerging trends potentially warranting further investigation from either a data quality or public health perspective. The code is available from the authors upon request. Output is highly customisable via CSV input and can be stratified on multiple levels.

Limited data exists on end-of-life (EOL) health care utilization in older patients (pts) with cancer. Via data linkage, this study aims to describe EOL care for older pts with cancer and explore the association between geriatric screening and assessment (GS/GA) results at cancer diagnosis and EOL care. Data linkage of GS/GA, cancer registry and administrative health data was performed based on a unique patient identifier. GS/GA data were derived from a large Belgian study (n=22 centers; 2009-2015) where pts aged ≥70 years were screened with G8 followed by GA in case of an abnormal G8 result (≤14/17). For this study pts with a new diagnosis were included when they died before end of follow-up (1/3/2019). Tumor characteristics and vital status were derived from cancer registry data and cause of death from death certificates. Place of death was derived from healthcare reimbursement data. 4,475 pts who died after a median of 13 months were included. The median age was 79 (range: 70–100) and 52.0% were female. Lung, breast and colon cancer were the most common diagnoses and 40.5% had stage IV disease. 81.8% of pts had an abnormal baseline G8. For 81.0% of pts the underlying cause of death was cancer (Table). The majority of pts died in a non-palliative care unit of the hospital (42.3%), followed by at home (25.4%), the palliative care unit of the hospital (16.8%) and nursing home (15.5%). When comparing pts with a normal and abnormal baseline G8 score, there were no major differences in cause and place of death except for a higher percentage with abnormal G8 dying in a nursing home (16.9% vs 9.3%).Table: 1265MOAll ptsPts with normal G8 score (>14/17)Pts with abnormal G8 score (≤14/17)(N=4,475)(N =814)(N =3,661)N (%)N (%)N (%)Underlying cause of deathCancer (ICD-10: C00-D48)3,260 (81.0)575 (83.3)2,685 (80.5)Other*764 (19.0)115 (16.7)649 (19.5)Missing451124327Place of deathHospital: non- palliative care unit1,892 (42.3)361 (44.3)1,531 (41.8)Hospital: palliative care unit753 (16.8)137 (16.8)616 (16.8)Nursing home693 (15.5)76 (9.3)617 (16.9)Home**1,137 (25.4)240 (29.5)897 (24.5)*most common: hearth failure, chronic obstructive pulmonary disease and acute myocardial infarction**place of death was considered home if the patient didn't die in hospital or nursing home Open table in a new tab *most common: hearth failure, chronic obstructive pulmonary disease and acute myocardial infarction **place of death was considered home if the patient didn't die in hospital or nursing home When older pts with a new cancer diagnosis die in the following years, cancer is the underlying cause of death for >80%, both for pts with normal and abnormal baseline G8 score. The majority of pts die in a hospital and only a quarter of pts die at home. This knowledge is important for incorporation of advanced care planning within this patient population.

Objective: To evaluate the effect of irregular screening behaviour on the risk of advanced stage breast cancer at diagnosis in Flanders. Methods: All women aged 50-69 who were invited to the organized breast cancer screening and diagnosed with breast cancer before age 72 from 2001 to 2018 were included. All prevalent screen and interval cancers within 2 years of a prevalent screen were excluded. Screening behaviour was categorized based on the number of invitations and performed screenings. Four groups were defined: regular, irregular, only-once, and never attenders. Advanced stage cancer was defined as a stage III + breast cancer. The association between screening regularity and breast cancer stage at diagnosis was evaluated in multivariable logistic regression models, taking age of diagnosis and socio-economic status into account. Results: In total 13.5% of the 38,005 breast cancer cases were diagnosed at the advanced stage. Compared to the regular attenders, the risk of advanced stage breast cancer for the irregular attenders, women who participated only-once, and never attenders was significantly higher with ORadjusted:1.17 (95%0:1.06-1.29) and ORadjusted:2.18 (95%CI:1.94-2.45), and ORadjusted:5.95 (95%CI:5.33-6.65), respectively. Conclusions: In our study, never attenders were nearly six times more likely to be diagnosed with advanced stage breast cancer than regular attenders, which was much higher than the estimates published thus far. An explanation for this is that the ever screened women is a heterogeneous group regarding the participation profiles which also includes irregular and only-once attenders. The benefit of regular screening should be informed to all women invited for screening.

Abstract 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.

Abstract BACKGROUND Quality Indicators (QIs) are important tools to assess the quality and variability of oncological care. However, their application in neuro-oncology is limited. The objective of this study was to develop a set of QIs for glioma, covering process and outcome indicators. METHODS First a systematic literature search was performed in peer-reviewed papers and grey literature to identify existing QIs in neuro-oncology and guidelines or recommendations that could be translated into new QIs. The PRISMA (Preferred Reporting Items for Systematic Review and Meta-Analyses) checklist and flow diagram were taken into account. The search strategy focused on diagnostics, treatment, follow-up and survival. For each (set of similar) recommendation(s) a QI was created that could easily be translated into a measurable proportion. Concordant QIs were rationalized to further reduce redundancy. Secondly a two round Delphi survey was organized amongst a multidisciplinary expert panel that was asked to score relevance for all proposed QIs. The panel consisted of neurosurgeons(4), radiation(3) and medical(3) oncologists, pathologists(3), radiologists(2), neurologists(1), nuclear medicine physicians(2) from university and non-university centers, and representatives of the Belgian Cancer Registry. RESULTS The conducted literature search in PubMed and Embase yielded 2392 abstracts. After screening and duplicate removal, 221 full text articles were assessed of which 79 were retained. In addition 28 references from the Grey literature were added. In total 240 recommendations and 30 QIs could be identified in this way. After translation of these recommendations into a measurable proportion, merging with the QIs found as such in the literature and rationalization, 148 QIs were presented to the expert panel. In the Delphi survey 15 of the 19 (79%) invited experts responded and eventually consensus was reached on 46 QIs that were considered relevant for the assessment of 6 different domains of neuro-oncological care: diagnosis and imaging (10), surgery (4), pathology (6), radio/chemotherapy (14), recurrence (5) and supportive treatment (7). CONCLUSION A set of 46 QIs grouped in 6 categories to assess the quality of care of glioma patients was developed. These QI’s are readily applicable dependent on the availability of population-based health care data

Background: Oncological care was considerably impacted by the COVID-19 pandemic. Worrisome declines in diagnostic procedures and cancer diagnoses in 2020 have been reported; however, nationwide, population-based evidence is limited. Quantification of the magnitude and distribution of the remaining outstanding diagnoses is likewise lacking. Methods: Using accelerated delivery of data from pathology laboratories to the Belgian Cancer Registry, we compared the nationwide rates of new diagnoses of invasive cancers in 2020 to 2019. Results: We observed a 44% reduction in total diagnoses of invasive cancers in April 2020 compared with April 2019, coinciding with the first wave of the COVID-19 pandemic. The reduction was largest in older patients and for skin cancers (melanoma and nonmelanoma). Reductions in diagnosis were less pronounced among children and adolescents (0-19 years). A smaller decline was observed for most cancers with typically poorer prognosis or obvious symptoms, including some hematological malignancies, lung, and pancreatic cancer. Suspension of organized population screening programs was reflected in a strong decline in diagnosis in the screening age groups for female breast cancer (56%) and for colorectal cancer in both men (49%) and women (60%). The number of diagnoses began to increase from the end of April and stabilized at the beginning of June at or just above 2019 levels. There has yet to be a complete recovery in cancer diagnoses, with an estimated 6%, or w4000 diagnoses, still outstanding for all of 2020. Among solid tumors, head and neck cancers have the largest remaining year-over-year decrease in diagnoses at 14%. Conclusion: These results add to the evidence of a profound impact of the COVID-19 pandemic on oncological care and identify groups at risk for continuing diagnostic delays. These data should stimulate health care providers worldwide to facilitate targeted, accessible, and efficient procedures for detection of cancers affected by this delay.

Abstract Background Data on non-organized colorectal cancer screening using fecal occult blood tests (FOBTs) is currently lacking. We identified factors associated with organized and non-organized FOBT screening. Methods Data of 308 municipalities in Flanders (6.6 million residents, 57% of Belgium) during 2015-2017 were analyzed. Logistic regression with generalized estimating equations was used to assess associations between municipal characteristics and organized and non-organized screening coverages. Results Median organized screening coverage increased (36.4% to 40.1%) while non-organized screening coverage decreased (4.8% to 3.3%) in 2015-2017. Organized screening coverage was negatively associated with average income (OR = 0.97, 95%CI: 0.96-0.98) and percentage of people with a non-Belgian/Dutch nationality (OR = 0.962, 95%CI: 0.957-0.967). More older people (70-74) in the target screening population were related to lower coverages by both organized (OR = 0.98, 95%CI: 0.97-0.99) and non-organized screening (OR = 0.98, 95%CI: 0.96-0.999). Education level was positively associated with organized screening coverage (OR = 1.010, 95%CI: 1.008-1.011). While GP visit was positively associated with both organized and non-organized screening coverages, average number of patients per GP and having a global medical dossier handled by preferred GP showed more pronounced associations with non-organized screening (OR = 1.021, 95%CI: 1.016-1.026 and OR = 1.025, 95%CI: 1.018-1.031, respectively) compared to organized screening coverage. Conclusions Higher average income, lower average education level, more older people and people with foreign nationality were associated with lower organized screening coverage. GP involvement showed a positive association with non-organized screening. It seems that some GPs and screening-invited individuals are still not fully aware of the benefits of organized screening. Available instruments in screening programs should be optimized to fill this gap in knowledge. Key messages We identified factors associated with both organized and non-organized colorectal cancer screening using fecal occult blood tests (FOBTs). Based on this knowledge, strategies can be developed to promote screening among non-participants and encourage non-organized participants to switch to organized screening.

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.

Abstract Introduction Net survival can be considered as the most accurate evaluation of survival from cancer, as it encompasses the survival that would occur if the only possible underlying cause of death was the cancer under study. Both relative survival (RS) and cause-specific survival (CSS) have been developed as approaches to estimate net survival at the population level. Given the debated accuracy of death certificates in identifying the underlying cause of death, RS measures are most commonly used by cancer registries. However, RS calculations can also be biased as it is sometimes unavoidable to match a group of cancer patients with a non-comparable disease-free population group. In this study, we aim to compare RS and CSS using causes of death obtained from death certificates in a cohort of Belgian breast cancer patients by evaluating them to CSS using causes of death obtained from medical files. Methods A total of 3,205 breast cancer patients diagnosed and treated in University Hospitals Leuven between 2009-2014 were included in this study. RS was calculated with the Ederer II method, dividing the observed survival by the expected survival for females of the same age and region. CSS was calculated using cause of death information either gathered from death certificates or collected from medical files. The estimates for RS and CSS as obtained from death certificates were compared to CSS obtained from medical files. Follow-up was guaranteed until 31th of December 2014. Results From the included cohort of breast cancer patients, 255 were deceased. Cause of death was available for 254 patients from death certificates and for 191 patients from medical files. By considering the available cause of death information, 3,141 patients were included to calculate the survival estimates. The 1-year relative survival estimate was 99.3% (95%CI, [98.7, 99.8]), while 1-year cause-specific survival based on death certificates was 99.0% [98.5, 99.3]. The 1-year survival estimate according to CSS based on medical files was 98.1% [97.5, 98.5]. The 5-year survival estimates were 95.8% [94.0, 97.4] for RS, 93.3% [91.8, 94.4] for CSS based on death certificates and 89.7% [88.0, 91.2] for CSS based on medical files. Conclusion This study used causes of death information as derived directly from medical files to calculate CSS in order to compare it with RS and CSS derived from death certificates. This allowed an evaluation of the RS and CSS estimates commonly used at the population level against the presumably more reliable CSS as obtained from medical files. Both RS and CSS from death certificates were divergent from CSS from medical files, but the CSS from death certificates appeared to be a closer estimate to CSS from medical files. After longer follow-up, both survival estimates seemed to deviate more from the CSS from medical files. Citation Format: Izci H, De Schutter H, Wildiers H, Neven P. Comparing estimates of survival for breast cancer patients [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P1-08-31.

Background: Known for its accessible health care, Belgium currently counts over 100 hospitals providing oncological care, resulting in shattered care which may negatively influence outcomes. In the context of recent centralization initiatives, this study aimed to evaluate relations between complex surgeries and outcomes for (peri)pancreatic and esophageal cancers at the Belgian population level. Methods: All patients with (peri)pancreatic (ICD)10: C25, C17.0, C24.0-1) or esophageal (C15-C16.0) cancer between 2007 and 2014 were extracted from the Belgian Cancer Registry and linked with surgeries (Sx) from reimbursement data. Concordant with previous reports, three yearly volume categories of Sx per center were defined ((peri)pancreatic: <6, 6-14 and ≥15 Sx/yr; esophageal: <6, 6-19 and ≥20 Sx/yr). Relations between surgical volumes and 30-days postoperative mortality as well as 5-year overall survival (OS) were analyzed with multivariable regression models adjusting for case-mix (including age, stage, sex, comorbidities). Results: 16,471 (peri)pancreatic and 12,241 esophageal cancers were retrieved, corresponding to 4,081 (peri)pancreatic and 3,387 esophageal cancer surgeries performed by 96 hospitals in total (in 2014: 68 hospitals for (peri)pancreatic and 54 for esophageal cancer Sx). Surgical volumes were significantly related with 30-days postoperative mortality for (peri)pancreatic and esophageal cancer (p = 0.005 and p < 0.0001 respectively), with 52% and 81% mortality reduction for high vs low volume hospitals, respectively. The volume effect was also seen for OS: for both cancer types, high volume hospitals had a better OS compared to low volume which remained significant after case mix adjustment. For (peri)pancreatic cancer, 1-yr and 5-yr OS for high versus low volume centers was 75% vs 69% and 34% vs 31%, respectively (HR 0.65 [0.55, 0.78], p < 0.0001). For esophageal cancer, 1-yr and 5-yr OS for high versus low volume centers was 79% vs 71% and 44% vs 38%, respectively (HR 0.88 [0.79;0.99], p = 0.04). Conclusions: High surgical volume centers showed better results for postoperative mortality and survival for (peri)pancreatic and esophageal cancers, supporting centralization initiatives in Belgium. Legal entity responsible for the study: Foundation Belgian Cancer Registry. Funding: Federal and Regional Authorities. Disclosure: All authors have declared no conflicts of interest.

Background: Pancreatic cancer (PaC) remains extremely lethal worldwide even after resection. This large international population-based study aimed at exploring factors associated with survival in resected PaC, and at developing and globally validating a survival-predicting nomogram. Methods: Data of PaC patients resected in 2003-2014 were obtained from multiple European national cancer registries and the US SEER-18 Program. Multivariable Cox proportional hazards models were constructed to investigate the associations of patient and tumor characteristics with overall survival. Prognostic factors remaining after backward selection in SEER-18 were used to build a nomogram, which was subjected to bootstrap internal validation and external validation using the European databases. Predictive accuracy was assessed using the concordance-index. Results: Totally 24,863 resected PaC patients were included, with median survival of 12-19 months and 3-year survival rates of 14%-28%. In main analysis, patient age, tumor T, N, and M stages, histology, and differentiation were significantly associated with survival, with country-specific association patterns and strengths. Additionally, hospital type, tumor size, harvested lymph node number, performance status, and certain comorbidities were associated with survival in countries with available information. A nomogram incorporating the backward-selected variables in the main analysis was established. Calibration curves showed good agreement between nomogram-prediction and actual observation. The concordance-index of the nomogram was significantly higher than that of the TNM staging for predicting survival. Conclusions: In these international population-based cohorts, resected PaC patients have distinct characteristics independently associated with survival. A personalized postoperative survival-predicting nomogram is established and internationally validated, which would be practical and helpful clinically and aid to patient stratification in international studies. Legal entity responsible for the study: Division of Clinical Epidemiology and Aging Research, German Cancer Research Center (DKFZ). Funding: German Cancer Aid (Deutsches Krebshilfe). Disclosure: All authors have declared no conflicts of interest.

The concept of multidisciplinary team meetings (MDTs) in cancer care is endorsed internationally, but its uptake varies considerably. In Belgium, MDT meetings were financially recognised in 2003 to encourage healthcare professionals to join their knowledge and competences to improve the quality and coordination of cancer care. This study aimed to evaluate for seven cancer types diagnosed between 2004 and 2011, the practices of MDT meetings in Belgium by means of population-based administrative databases. Results show a clear increase over time in the proportion of individual patients discussed at MDT meetings. Although this evolution may be partly explained by the legal implementation of several financial initiatives to stimulate MDT meetings, it also suggests an increase in specialists' awareness of the importance of such meetings. Nevertheless, there is still room for improvement, for specific cancer types as well as for certain subgroups such as older patients. From the specialists' point of view, reducing the administrative burden and time these meetings demand may entail a greater participation to MDT meetings. Further research is needed to identify the barriers to discuss more patients at MDT meetings and to elucidate the impact of MDT meetings on the quality of cancer care.

Background: As older gastric cancer patients are often excluded from randomized clinical trials, the most appropriate treatment strategy for these patients remains unclear. The current study aimed to gain more insight in treatment strategies and relative survival of older patients with resectable gastric cancer across Europe. Methods: Population-based cohorts from Belgium, Denmark, The Netherlands, Norway, and Sweden were combined. Patients >= 70 years with resectable gastric cancer (cT1-4a, cNO-2, cM0), diagnosed between 2004 and 2014 were included. Resection rates, administration of chemotherapy (irrespective of surgery), and relative survival within a country according to stage were determined. Results: Overall, 6698 patients were included. The percentage of operated patients was highest in Belgium and lowest in Sweden for both stage II (74% versus 56%) and stage III disease (57% versus 25%). For stage III, chemotherapy administration was highest in Belgium (44%) and lowest in Sweden (2%). Three year relative survival for stage I, II, and Ill disease in Belgium was 67.8% (95% CI:62.8-72.6), 41.2% (95% CI:37.3-45.2), 17.8% (95% CI:12.5-24.0), compared with 56.7% (95% CI:51.5-61.7), 31.3% (95% CI:27.6 -35.2), 8.2% (95% CI:4.4-13.4) in Sweden. There were no significant differences in treatment strategies of patients with stage I disease. Conclusion: Substantial treatment differences are observed across North European countries for patients with stages II and III resectable gastric cancer aged 70 years or older. In the present comparison, treatment strategies with a higher proportion of patients undergoing surgery seemed to be associated with higher survival rates for patients with stages II or III disease. (C) 2018 Published by Elsevier Ltd.

In the randomized Asian REGATTA trial, no survival benefit was shown for additional gastrectomy over chemotherapy alone in patients with advanced gastric cancer with a single incurable factor, thereby discouraging surgery for these patients. The purpose of this study was to evaluate treatment strategies for patients with metastatic gastric cancer in daily practice in five European countries, along with relative survival in each country. Nationwide population-based data from Belgium, Denmark, the Netherlands, Norway and Sweden were combined. Patients with primary metastatic gastric cancer diagnosed between 2006 and 2014 were included. The proportion of gastric resections performed and the administration of chemotherapy (irrespective of surgery) within each country were determined. Relative survival according to country was calculated. Overall, 15 057 patients with gastric cancer were included. The proportion of gastric resections varied from 8·1 per cent in the Netherlands and Denmark to 18·3 per cent in Belgium. Administration of chemotherapy was 39·2 per cent in the Netherlands, compared with 63·2 per cent in Belgium. The 6-month relative survival rate was between 39·0 (95 per cent c.i. 37·8 to 40·2) per cent in the Netherlands and 54·1 (52·1 to 56·9) per cent in Belgium. There is variation in the use of gastrectomy and chemotherapy in patients with metastatic gastric cancer, and subsequent differences in survival.