Regional variation in incidence for smoking and alcohol related cancers in Belgium

Incidence, survival, and mortality of cancer in children and young adolescents in Belgium and the Netherlands in 2004-2015: A comparative population-based study

International comparisons of cancer surveillance measures may provide insight into inequalities in registration practices, etiological factors, and treatment strategies. This study aimed to compare incidence, survival, and mortality of cancer in children and young adolescents between Belgium and the Netherlands. All children (0-14 years) and young adolescents (15-17 years) diagnosed with cancer between 2004 and 2015 were selected from the population-based cancer registries of Belgium (N = 4739) and the Netherlands (N = 7322). Differences in incidence and mortality were expressed as standardized rate ratios (SRR; BE/NL). Five-year observed survival was calculated using the Kaplan-Meier method. During 2004-2015, the overall cancer incidence among children and young adolescents was similar in both countries. Incidence of neuroblastoma was significantly higher in Belgian children (2010-2015: SRR = 1.3, 95% CI 1.0-1.6). Five-year survival of all malignant cancers was comparable in 2010-2015, exceeding 80% in both age groups. Remarkable differences in survival existed in children for malignant central nervous system (CNS) tumors in 2004-2009 (BE = 62%, NL = 45%), for acute myeloid leukemia (BE = 68%, NL = 78%) and rhabdomyosarcomas (BE = 60%, NL = 79%) in 2010-2015, and for neuroblastoma in both periods (2004-2009: BE = 76%, NL = 64%; 2010-2015: BE = 82%, NL = 64%). Overall cancer mortality in children decreased by approximately 3 percent-points annually in both countries, but was slightly lower in Belgium in 2004-2009 (SRR = 0.9, 95% CI 0.7-1.0). Despite differences for specific cancer types, overall cancer incidence, survival, and mortality were comparable between Dutch and Belgian children and young adolescents in 2010-2015. Variability in screening, diagnosis, and registration practices probably explains the observed differences in incidence and survival of neuroblastoma and malignant CNS tumors.

Survival of patients with unfavorable prognosis cutaneous melanoma with increased use of immunotherapy agents: a population-based study in Belgium

BACKGROUND

Although metastatic cutaneous melanoma is associated with an unfavorable prognosis, innovative therapies including immunomodulating agents and targeted therapies have shown survival benefits in clinical trials. We assessed the impact of the introduction of innovative drugs into clinical practice on the survival of patients with metastatic cutaneous melanoma during the period 2004-2017, in Belgium. The evolution of associated expenses was also analyzed.

METHODS

This is a retrospective population-based study using data from the national Belgian Cancer Registry, compulsory health insurance, and administrative survival data. The immunomodulating drugs were ipilimumab, nivolumab and pembrolizumab, while targeted therapies included vemurafenib, dabrafenib and trametinib.

RESULTS

We did not identify a trend for improvement over time. Median survival (years) was 1.5 (95% CI: 1.1-1.8) in 2004-2008, 1.1 (95% CI: 0.8-1.5) in 2009-2013, and 1.6 (95% CI: 1.3-2.4) in 2014-2017, respectively. In contrast, survival improved in those with unknown primary tumor localization. In this group, median survival time was 2.0 (95% CI: 1.4-2.9) in the most recent period, while it was 1.1 (95% CI: 0.7-1.3) in 2009-2013, and 0.9 (95% CI: 0.6-1.2) in 2004-2008. The uptake of innovative drugs remained modest, with no drug being used by more than 30% of patients. Yearly expenditure was almost non-existent, and gradually increased, reaching several million euros in 2014-2017.

CONCLUSION

Patients with metastatic cutaneous melanoma who were diagnosed between 2004 and 2017 showed no apparent improvement in survival. In contrast, increased survival was observed in the subgroup of patients with unknown primary tumor localization.

Cancer incidence, stage shift and survival during the 2020 COVID-19 pandemic: A population-based study in Belgium

The COVID-19 pandemic was associated with a profound decline in cancer diagnoses in 2020 in Belgium. Disruption in diagnostic and screening services and patient reluctance to visit health facilities led to fewer new cases and concerns that cancers may be diagnosed at more advanced stages and hence have poorer prognosis. Using data from mandatory cancer registration covering all of Belgium, we predicted cancer incidence, stage distribution and 1-year relative survival for 2020 using a Poisson count model over the preceding years, extrapolated to 2020 for 11 common cancer types. We compared these expected values to the observed values in 2020 to specifically quantify the impact of the COVID-19 pandemic, accounting for background trends. A significantly lower incidence was observed for cervical, prostate, head and neck, colorectal, bladder and breast cancer, with limited or no recovery of diagnoses in the second half of 2020 for these cancer types. Changes in stage distribution were observed for cervical, prostate, bladder and ovarian and fallopian tube tumours. Generally, changes in stage distribution mainly represented decline in early-stage than in late-stage tumours. One-year relative survival was lower than predicted for lung cancer and colorectal cancer. Stage shifts are hypothesised to result from alterations in access to diagnosis, potentially due to prioritisation of symptomatic patients, and patient reluctance to contact a physician. Since there were over 5000 fewer cancer diagnoses than expected by the end of 2020, it is critical to monitor incidence, stage distribution and survival for these cancers in the coming years.

Quality of surgery and treatment and its association with hospital volume: A population-based study in more than 5000 Belgian ovarian cancer patients

BACKGROUND

Different sets of quality indicators are used to identify areas for improvement in ovarian cancer care. This study reports transparently on how (surgical) indicators were measured and on the association between hospital volume and indicator results in Belgium, a country setting without any centralisation of ovarian cancer care.

METHODS

From the population-based Belgian Cancer Registry, patients with a borderline malignant or invasive epithelial ovarian tumour diagnosed between 2014 and 2018 were selected and linked to health insurance and vital status data (n = 5119). Thirteen quality indicators on diagnosis and treatment were assessed and the association with hospital volume was analysed using logistic regression adjusted for case-mix.

RESULTS

The national results for most quality indicators on diagnosis and systemic therapy were around the predefined target value. Other indicators showed results below the benchmark: genetic testing, completeness of staging surgery, lymphadenectomy with at least 20 pelvic/para-aortic lymph nodes removed, and timely start of chemotherapy after surgery (within 42 days). Ovarian cancer care in Belgium is dispersed over 100 hospitals. Lower volume hospitals showed poorer indicator results compared to higher volume hospitals for lymphadenectomy, staging, timely start of chemotherapy and genetic testing. In addition, surgery for advanced stage tumours was performed less often in lower volume hospitals.

CONCLUSIONS

The indicators that showed poorer results on a national level were also those with poorer results in lower-volume hospitals compared to higher-volume hospitals, consequently supporting centralisation. International benchmarking is hampered by different (surgical) definitions between countries and studies.

Impact of the COVID-19 Pandemic on Incidence and Observed Survival of Malignant Brain Tumors in Belgium

(1) Background: This study evaluates the impact of the COVID-19 pandemic on the incidence, treatment, and survival of adults diagnosed with malignant brain tumors in Belgium in 2020. (2) Methods: We examined patients aged 20 and older with malignant brain tumors (2004-2020) from the Belgian Cancer Registry database, assessing incidence, WHO performance status, vital status, and treatment data. We compared 2020 incidence rates with projected rates and age-standardized rates to 2015-2019. The Kaplan-Meier method was used to assess observed survival (OS). (3) Results: In 2020, there was an 8% drop in age-specific incidence rates, particularly for those over 50. Incidence rates plunged by 37% in April 2020 during the first COVID-19 peak but partially recovered by July. For all malignant brain tumors together, the two-year OS decreased by four percentage points (p.p.) in 2020 and three p.p. in 2019, compared to that in 2015-2018. Fewer patients (-9 p.p.) with glioblastoma underwent surgery, and the proportion of patients not receiving surgery, radiotherapy, or systemic therapy increased by six percentage points in 2020. (4) Conclusions: The COVID-19 pandemic profoundly impacted the diagnosis, treatment strategies, and survival of brain tumor patients in Belgium during 2020. These findings should guide policymakers in future outbreak responses, emphasizing the need to maintain or adapt (neuro)-oncological care pathways and promote informed decision making when care capacity is limited.

Stage shift and relative survival for head and neck cancer during the 2020 COVID-19 pandemic: a population-based study of temporal trends

Objective

During the first wave of the COVID-19 pandemic in 2020, non-essential health services were suspended in Belgium, and the public was ordered to socially isolate. Underdiagnosis of cancer during this period was reported worldwide. Certain risk factors for head and neck cancer (HNC) overlap with those for COVID-19 incidence and mortality, making underdiagnosis and subsequent stage shift of this potentially rapidly progressing cancer a major concern. We aimed to analyze incidence, clinical stage at presentation, and survival of patients diagnosed with HNC in 2020 in Belgium, considering recent temporal trends.

Methods

Using population-based data from the Belgian Cancer Registry (BCR), we extrapolated 2017-2019 trends in incidence, clinical stage, and 1-year relative survival (1yRS) of HNC to create an expected value for 2020 and compared this to the observed value.

Results

There were 9.5% fewer HNCs diagnosed in 2020, compared to the predicted incidence. Underdiagnosis was larger for males (-11.8%), patients aged 50-64 (-11.2%) and 65-79 (-11.1%), and for oral cavity cancer (-17.6%). Shifts to more advanced stages were observed in larynx and oropharynx tumors and for (male) patients aged 80+. A 2.4 percentage point decline in 1yRS was observed, relative to the increasing trends in 1yRS (2017-2019).

Conclusion

The COVID-19 pandemic led to underdiagnosis of HNC, resulting in shifts to more advanced stage at presentation in certain subgroups. A stage shift can be expected for the 9.5% of tumors not yet diagnosed at the end of 2020. HNC patients diagnosed in 2020 suffered higher than expected mortality.

Epidemiological Trends of Haematological Malignancies in Belgium 2004-2018: Older Patients Show the Greatest Improvement in Survival

(1) Background: Haematological malignancies (HMs) represent a heterogeneous group of mostly rare cancers that differ in pathophysiology, incidence, and outcome. (2) Methods: Our study aims to understand the epidemiological situation and trends of 24 main types of HMs in Belgium over a 15-year period, with a focus on the impact of age. Age-standardised incidence, average annual percentage change (AAPC), 5- and 10-year relative survival (RS) and RS trends were estimated for all HMs (N = 94,415) diagnosed between 2004 and 2018. (3) Results: Incidence rates of HM increased, mainly in the 70+ age group (AAPC: 3%). RS varied by age and HM type. For each HM type, outcome decreased with age. The greatest decrease with age in 5-year RS is observed for aggressive HM, acute myeloid leukaemia (AML), acute lymphoblastic leukaemia, and Burkitt lymphoma, from 67%, 90%, and 97% below 20 years, to 2%, 12%, and 16% above 80 years of age, respectively. The moderate improvement in 5-year RS over the 2004-2018 period for all HMs, of +5 percentage point (pp), masks highly heterogenous outcomes by HM type and age group. The most impressive improvements are observed in the 80+ group: +45, +33, +28, and +16 pp for Hodgkin lymphoma, immunoproliferative disorders, follicular lymphoma, and chronic myeloid leukaemia, respectively. (4) Conclusions: The increasing incidence and survival over the 2004-2018 period are likely explained by diagnostic and therapeutic innovations, which have spread to populations not targeted by clinical trials, especially older adults. This real-world population-based study highlights entities that need significant improvement, such as AML.

The epidemiology of multiple primary cancers in Belgium (2004-2017): Incidence, proportion, risk, stage and impact on relative survival estimates

BACKGROUND

As both life expectancy and cancer survival improve, the incidence of multiple primary cancer has augmented and is expected to further increase. This study describes for the first time the epidemiology of multiple invasive tumours in Belgium.

METHODS

This nationwide study, based on all cancers diagnosed between 2004 and 2017 in Belgium, describes the proportion of multiple primary cancer, its evolution over time, the impact of inclusion or exclusion of multiple primary cancer on relative survival estimates, the risk of developing a second primary cancer, and the difference in stage between first and second primary cancer for the same patient.

RESULTS

The proportion of multiple primary cancer increases with age, varies across cancer sites (from 4% for testis cancer to 22.8% for oesophageal cancer), is higher in men than in women, and has linearly increased over time. The inclusion of multiple primary cancer resulted in smaller 5-year relative survival and this impact is more pronounced in cancer sites with high relative survival. Patients with a first primary cancer have an increased risk to develop a new primary cancer compared to the population without a previous cancer history (1.27 and 1.59 times higher in men and women, respectively) and this risk depends on cancer site. Second primary cancers are associated with more advanced stages and more unknown stages than the corresponding first cancer diagnosis.

CONCLUSIONS

This study describes multiple primary cancer according to several measures (proportion, standardised incidence ratio for an second primary cancer, impact of multiple primary cancer on relative survival and differences according to stage) for the first time in Belgium. The results are based on data of a population-based cancer registry with a relatively recent onset (2004).

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.

Belgian observational survival data (incidence years 2004-2017) and expenditure for innovative oncology drugs in twelve cancer indications

BACKGROUND

The Food and Drug Administration and European Medicines Agency typically approve market access for cancer drugs based on surrogate end-points, which do not always translate into substantiated improvements in outcomes that matter the most to patients, i.e. survival and quality of life. These drugs often, also, have a high price tag. We assessed whether there was an increase in cancer drug expenditure for a broad selection of indications, and whether this correlates with increased overall survival.

METHODS

This cohort study used Belgian Cancer Registry data from 125,692 patients (12 cancer indications, incidence period 2004-2017), which was linked to reimbursement and survival data. This reliably represents the Belgian situation. One-to-five year observed survival probability, median survival time, oncology drug expenditure and mean oncology drug cost per patient were reviewed.

FINDINGS

In almost all indications, total expenditure and average treatment cost for oncology drugs increased over the years (2004-2017). In contrast, mixed findings are observed for the evolution in overall survival probability and median survival time. While an absolute improvement in the 3-year survival probability of about 10% is noticed in non-small-cell lung cancer and chronic myeloid leukaemia, improvements in about half of the other indications are limited or even absent.

INTERPRETATION

The Belgian observational data indicate that assuming 'innovative' oncology drugs always add value in terms of improved survival is often unjustified. The literature also highlights the problem of using surrogate end-points, and the lack of comparative evidence showing an added value of oncology drugs for both survival and quality of life at market approval or during the post-marketing phase. Comparative studies should be conducted in the pre-marketing phase that are suitable for registration purposes, aid reimbursement decisions and support physicians and patients when making treatment decisions.

Survival in stage IV ovarian cancer with increased use of debulking surgery and bevacizumab

OBJECTIVES

Advanced ovarian cancer has a poor prognosis, with a 5 year survival probability of <30%. Attempts to improve survival have focused on debulking surgery and systemic therapy. We assessed the evolution of treatment patterns and survival of patients with advanced epithelial ovarian cancer with specific attention to changes in survival after introducing bevacizumab.

METHODS

Population based data from the Belgian Cancer Registry were coupled with administrative reimbursement data from the compulsory health insurance organizations and the national database where date of death is registered, based on the patient's unique national number. Patients with epithelial ovarian cancer stage IV diagnosed in 2004-17 were included. The proportion of patients who underwent debulking surgery and received bevacizumab was calculated per incidence year. Survival was compared for the three incidence periods (2004-08, 2009-13, 2014-17) and before and after the introduction of bevacizumab.

RESULTS

2034 patients with stage IV epitheial ovarian cancer were included. From 2012 onwards, uptake of bevacizumab increased, with 50% of patients with stage IV ovarian cancer diagnosed in 2017 receiving bevacizumab. The proportion of stage IV patients who underwent debulking surgery also increased over time, from 21.1% in 2004-08 to 50.4% and 45.4% in 2009-13 and 2014-17, respectively. The 3 year observed survival probability fluctuated between 27% and 42% without a trend over time. The increase in debulking surgery was associated with improved survival (hazard ratio (HR) 0.88, 95% confidence interval (CI) 0.79 to 0.98) but the introduction of bevacizumab was not (HR 0.94, 95% CI 0.85 to 1.03). For patients diagnosed in 2004, the mean cost per patient treated with oncological drugs was about €12 500, which doubled to about €25 000 for patients diagnosed in 2014 or later.

CONCLUSIONS

Despite a rise in the use of debulking surgery and the introduction of bevacizumab into clinical practice, no improvement in 3 year survival probability was observed for patients with advanced ovarian cancer in Belgium.

Completeness and selection bias of a Belgian multidisciplinary, registration-based study on the EFFectiveness and quality of Endometrial Cancer Treatment (EFFECT)

BACKGROUND

With the aim of obtaining more uniformity and quality in the treatment of corpus uteri cancer in Belgium, the EFFECT project has prospectively collected detailed information on the real-world clinical care offered to 4063 Belgian women with primary corpus uteri cancer. However, as data was collected on a voluntary basis, data may be incomplete and biased. Therefore, this study aimed to assess the completeness and potential selection bias of the EFFECT database.

METHODS

Five databases were deterministically coupled by use of the patient's national social security number. Participation bias was assessed by identifying characteristics associated with hospital participation in EFFECT, if any. Registration bias was assessed by identifying patient, tumor and treatment characteristics associated with patient registration by participating hospitals, if any. Uni- and multivariable logistic regression were applied.

RESULTS

EFFECT covers 56% of all Belgian women diagnosed with primary corpus uteri cancer between 2012 and 2016. These women were registered by 54% of hospitals, which submitted a median of 86% of their patients. Participation of hospitals was found to be biased: low-volume and Walloon-region centers were less likely to participate. Registration of patients by participating hospitals was found to be biased: patients with a less favorable risk profile, with missing data for several clinical-pathological risk factors, that did not undergo curative surgery, and were not discussed in a multidisciplinary tumor board were less likely to be registered.

CONCLUSIONS

Due to its voluntary nature, the EFFECT database suffers from a selection bias, both in terms of the hospitals choosing to participate and the patients being included by participating institutions. This study, therefore, highlights the importance of assessing the selection bias that may be present in any study that voluntarily collects clinical data not otherwise routinely collected. Nevertheless, the EFFECT database covers detailed information on the real-world clinical care offered to 56% of all Belgian women diagnosed with corpus uteri cancer between 2012 and 2016, and may therefore act as a powerful tool for measuring and improving the quality of corpus uteri cancer care in Belgium.

The non-fatal burden of cancer in Belgium, 2004-2019: a nationwide registry-based study

BACKGROUND

The importance of assessing and monitoring the health status of a population has grown in the last decades. Consistent and high quality data on the morbidity and mortality impact of a disease represent the key element for this assessment. Being increasingly used in global and national burden of diseases (BoD) studies, the Disability-Adjusted Life Year (DALY) is an indicator that combines healthy life years lost due to living with disease (Years Lived with Disability; YLD) and due to dying prematurely (Years of Life Lost; YLL). As a step towards a comprehensive national burden of disease study, this study aims to estimate the non-fatal burden of cancer in Belgium using national data.

METHODS

We estimated the Belgian cancer burden from 2004 to 2019 in terms of YLD, using national population-based cancer registry data and international disease models. We developed a microsimulation model to translate incidence- into prevalence-based estimates, and used expert elicitation to integrate the long-term impact of increased disability due to surgical treatment.

RESULTS

The age-standardized non-fatal burden of cancer increased from 2004 to 2019 by 6 and 3% respectively for incidence- and prevalence-based YLDs. In 2019, in Belgium, breast cancer had the highest morbidity impact among women, followed by colorectal and non-melanoma skin cancer. Among men, prostate cancer had the highest morbidity impact, followed by colorectal and non-melanoma skin cancer. Between 2004 and 2019, non-melanoma skin cancer significantly increased for both sexes in terms of age-standardized incidence-based YLD per 100,000, from 49 to 111 for men and from 15 to 44 for women. Important decreases were seen for colorectal cancer for both sexes in terms of age-standardized incidence-based YLD per 100,000, from 105 to 84 for men and from 66 to 58 for women.

CONCLUSIONS

Breast and prostate cancers represent the greatest proportion of cancer morbidity, while for both sexes the morbidity burden of skin cancer has shown an important increase from 2004 onwards. Integrating the current study in the Belgian national burden of disease study will allow monitoring of the burden of cancer over time, highlighting new trends and assessing the impact of public health policies.

Machine Learning-Based Extraction of Breast Cancer Receptor Status From Bilingual Free-Text Pathology Reports

As part of its core business of gathering population-based information on new cancer diagnoses, the Belgian Cancer Registry receives free-text pathology reports, describing results of (pre-)malignant specimens. These reports are provided by 82 laboratories and written in 2 national languages, Dutch or French. For breast cancer, the reports characterize the status of estrogen receptor, progesterone receptor, and Erb-b2 receptor tyrosine kinase 2. These biomarkers are related with tumor growth and prognosis and are essential to define therapeutic management. The availability of population-scale information about their status in breast cancer patients can therefore be considered crucial to enrich real-world scientific studies and to guide public health policies regarding personalized medicine. The main objective of this study is to expand the data available at the Belgian Cancer Registry by automatically extracting the status of these biomarkers from the pathology reports. Various types of numeric features are computed from over 1,300 manually annotated reports linked to breast tumors diagnosed in 2014. A range of popular machine learning classifiers, such as support vector machines, random forests and logistic regressions, are trained on this data and compared using their F₁ scores on a separate validation set. On a held-out test set, the best performing classifiers achieve F₁ scores ranging from 0.89 to 0.92 for the four classification tasks. The extraction is thus reliable and allows to significantly increase the availability of this valuable information on breast cancer receptor status at a population level.

Decline and incomplete recovery in cancer diagnoses during the COVID-19 pandemic in Belgium: a year-long, population-level analysis

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 ∼4000 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.

Excess Mortality in a Nationwide Cohort of Cancer Patients during the Initial Phase of the COVID-19 Pandemic in Belgium

BACKGROUND

Most studies investigating the impact of coronavirus infectious disease-19 (COVID-19) on mortality among patients with cancer were performed in a hospital setting, and the evidence is thus based on a selected and frail subset of patients. This study evaluates the excess mortality during the first wave of COVID-19 in a nationwide, prevalent cancer cohort in Belgium.

METHODS

Mortality was studied among almost 240,000 patients with cancer diagnosed between 2013 and 2018 and alive on January 1, 2020. The observed number of deaths in the months January to June 2020 was compared with the expected number of deaths applying the monthly mortality rates observed in the cancer cohort during the previous years. A comparison using the excess mortality rates from the general population was performed.

RESULTS

An excess number of deaths of about 400 was observed in the month of April, coinciding with a peak of COVID-19 diagnoses in Belgium and corresponding to a 33% rise in mortality. A comparable number of excess deaths was estimated if the COVID-19 excess mortality rates from the general Belgian population were applied to the cancer cohort, stratified by age and sex.

CONCLUSIONS

A considerable excess mortality in the Belgian cancer cohort was observed during the initial peak of COVID-19 in Belgium. The pattern of excess mortality was, however, not markedly different from that observed in the general population.

IMPACT

These results suggest that the susceptibility of prevalent cancer patients to COVID-19-induced mortality during the first wave of the pandemic was comparable with the general population.

Patterns and quality of care for head and neck cancer in Belgium: A population-based study

OBJECTIVES

We evaluated the quality of care for patients with squamous cell carcinoma (SCC) of the oral cavity, oropharynx, hypopharynx or larynx in Belgium.

METHODS

Data of the Belgian Cancer Registry were coupled with health insurance data and hospital discharge data. Quality of care and the association with hospital volume were evaluated based on six quality indicators.

RESULTS

Half of the patients were treated with primary radiotherapy, with or without systemic therapy (49.7%) and 38.1% with surgery, with or without (neo)adjuvant therapy. Single-modality treatment was provided to 78.1% of early-disease patients. Of the patients with cN0 disease, 56.4% underwent neck dissection. Postoperative radiotherapy was completed timely in 48.5% of patients. Concomitant chemotherapy was administered to 58.2% of patients <70 years with locally advanced disease. Imaging of the neck after radiotherapy was performed appropriately in 32.7% of patients. Variability between centres was considerable. No clear relationship between hospital volume and results of the individual QIs was observed.

CONCLUSIONS

Results show that for the measured QIs, targets are not met and variability between centres is considerable. Through individual feedback, centres are motivated to improve the quality of care for head and neck cancer patients in Belgium.

Lung cancer incidence differences in migrant men in Belgium, 2004-2013: histology-specific analyses

BACKGROUND

Immigrants make up an important share of European populations which has led to a growing interest in research on migrants' health. Many studies have assessed migrants' cancer mortality patterns, yet few have studied incidence differences. This paper will probe into histology-specific lung cancer incidence by migrant origin aiming to enhance the knowledge on lung cancer aetiology and different risk patterns among population groups.

METHODS

We used data on all lung cancer diagnoses during 2004-2013 delivered by the Belgian Cancer Registry individually linked with the 2001 Belgian Census and the Crossroads Bank for Social Security. Absolute and relative inequalities in overall and histology-specific lung cancer incidence have been calculated for first-generation Italian, Turkish and Moroccan migrant men aged 50-74 years compared to native Belgian men.

RESULTS

Moroccan men seemed to be the most advantaged group. Both in absolute and relative terms they consistently had lower overall and histology-specific lung cancer incidence rates compared with native Belgian men, albeit less clear for adenocarcinoma. Turkish men only showed lower overall lung cancer incidence when adjusting for education. On the contrary, Italian men had higher incidence for overall lung cancer and squamous cell carcinoma, which was explained by adjusting for education.

CONCLUSIONS

Smoking habits are likely to explain the results for Moroccan men who had lower incidence for smoking-related histologies. The full aetiology for adenocarcinoma is still unknown, yet the higher incidence among Italian men could point to differences in occupational exposures, e.g. to carcinogenic radon while working in the mines.

Childhood leukemia near nuclear sites in Belgium: An ecological study at small geographical level

BACKGROUND

A previous investigation of the occurrence of childhood acute leukemia around the Belgian nuclear sites has shown positive associations around one nuclear site (Mol-Dessel). In the following years, the Belgian Cancer Registry has made data available at the smallest administrative unit for which demographic information exists in Belgium, i.e. the statistical sector. This offers the advantage to reduce the potential misclassification due to large geographical scales.

METHODS

The current study performed for the period 2006-2016 uses Poisson models to investigate (i) the incidence of childhood acute leukemia within 20 km around the four Belgian nuclear sites, (ii) exposure-response relationships between cancer incidence and surrogate exposures from the nuclear sites (distance, wind direction frequency and exposure by hypothetical radioactive discharges taking into account historical meteorological conditions). All analyses are carried out at statistical sector level.

RESULTS

Higher incidence rate ratios were found for children <15 years (7 cases, RR = 3.01, 95% CI: 1.43;6.35) and children <5 years (< 5 cases, RR = 3.62, 95% CI: 1.35;9.74) living less than 5 km from the site of Mol-Dessel. In addition, there was an indication for positive exposure-response relationships with the different types of surrogate exposures.

CONCLUSION

Results confirm an increased incidence of acute childhood leukemia around Mol-Dessel, but the number of cases remains very small. Random variation cannot be excluded and the ecological design does not allow concluding on causality. These findings emphasize the need for more in-depth research into the risk factors of childhood leukemia, for a better understanding of the etiology of this disease.

Incidence and survival of cutaneous melanoma in Belgium and the Netherlands from 2004 to 2016: striking differences and similarities of two neighbouring countries

BACKGROUND

Cutaneous melanoma (CM) is a multifactorial disease, with both environmental and genetic factors involved. The incidence of CM has risen rapidly during the last decades, making it a growing public health problem.

OBJECTIVES

The purpose of this retrospective study was to compare incidence and survival data of CM between two neighbouring countries, Belgium (BE) and the Netherlands (NL).

METHODS

Data were collected by the Belgian Cancer Registry (BCR) and the Netherlands Cancer Registry (NCR) from 1 January 2004 until 31 December 2016. Mucosal melanoma, in situ CM and melanoma in children from 0 to 14 years were excluded. Age-standardized incidence rates were calculated using the World Standard Population (WSR) per 100 000 persons. Five-year relative survival ratios were calculated using the Ederer II methodology.

RESULTS

Total number of CM was higher in NL (63 789) compared with BE (27 679). The WSR was 1.5 times higher in NL compared with BE (27.7 vs. 18.6/100 000/year). The WSR of stage IV tumours was higher in BE than in NL (0.3 vs. 0.2/100 000/year). Five-year relative survival of stage IV tumours was higher in BE compared with NL (27.2% vs. 13.7%).

CONCLUSIONS

Incidence of CM was higher in NL, indicating a higher risk of CM diagnosis. Stage IV tumours were relatively more frequent in BE for both sexes, while relative survival of stage IV tumours was higher in BE. As geographical location and latitude of both neighbouring countries are almost identical, other factors like differences in behaviour, follow-up and/or treatment may explain these differences.

Cancer risk among individuals of migrant origin in Belgium during the 2000s - Evidence of migration as a 'cancer risk transition'?

Recent research has shown a generally lower cancer risk and mortality among migrants from less-industrialised country origin. However, while rates are usually lower for 'lifestyle-related' cancers (e.g. breast, prostate, lung, colorectal), they are typically elevated for 'infection-related' ones such as liver and stomach cancer. Although these observations appear in line with the theory of 'migration as a rapid epidemiological transition', changes in cancer risk after migration have yet to be investigated, effectively testing if migration also entails a 'rapid cancer risk transition'. This study therefore examines cancer risk among migrants in Belgium, focusing on colorectal cancer as a typically lifestyle-related cancer on the one hand, and infection-related cancers on the other hand. We subdivide migrant groups of more and less industrialised country origin according to duration of stay, and calculate absolute and relative incidence rates between 2004 and 2013. Our findings corroborate the transition assumptions for men from Turkey and Morocco, but cannot support them for women. Italian male immigrants have an in-between position: their colorectal cancer risk does not differ from that of Belgian men, but infection-related and non-cardia stomach cancer risks are higher and remain so with longer duration of stay. The fact that rates for migrants from the Netherlands and France generally do not differ from those of Belgians further strengthens support for a cancer transition among male migrants. Further examinations should focus on changes in health-related behaviour that can explain persistently low colorectal cancer risks among Turkish and Moroccan migrants and can inform preventive strategies for other population subgroups. Knowledge about the higher non-cardia stomach cancer risk among Turkish, Moroccan, and Italian men can support early detection strategies by primary care providers when patients present with gastric symptoms, especially because this cancer tends to have unfavourable prognosis.

On the impact of residential history in the spatial analysis of diseases with a long latency period: A study of mesothelioma in Belgium

Mesothelioma is a rare cancer caused by exposure to asbestos. Belgium has a known long history of asbestos production, resulting in one of the highest mesothelioma mortality rates worldwide. While the production of asbestos has stopped completely, the long latency period of mesothelioma, which can fluctuate between 20 and 40 years after exposure, causes incidences still to be frequent. Mesothelioma's long incubation time affects our assessment of its geographical distribution as well. Since patients' residential locations are likely to change a number of times throughout their lives, the location where the patients develop the disease is often far from the location where they were exposed to asbestos. Using the residential history of patients, we propose the use of a convolution multiple membership model (MMM), which includes both a spatial conditional autoregressive and an unstructured random effect. Pancreatic cancer patients are used as a control population, reflecting the population at risk for mesothelioma. Results show the impact of the residential mobility on the geographical risk estimation, as well as the importance of acknowledging the latency period of a disease. A simulation study was conducted to investigate the properties of the convolution MMM. The robustness of the results for the convolution MMM is assessed via a sensitivity analysis.

Association Between Treatment With Apixaban, Dabigatran, Rivaroxaban, or Warfarin and Risk for Osteoporotic Fractures Among Patients With Atrial Fibrillation: A Population-Based Cohort Study

BACKGROUND

It is unclear whether anticoagulant type is associated with the risk for osteoporotic fracture, a deleterious complication of anticoagulants among patients with atrial fibrillation (AF).

OBJECTIVE

To compare the risk for osteoporotic fracture between anticoagulants.

DESIGN

Population-based cohort study.

SETTING

Territory-wide electronic health record database of the Hong Kong Hospital Authority.

PARTICIPANTS

Patients newly diagnosed with AF between 2010 and 2017 who received a new prescription for warfarin or a direct oral anticoagulant (DOAC) (apixaban, dabigatran, or rivaroxaban). Follow-up ended on 31 December 2018.

MEASUREMENTS

Osteoporotic hip and vertebral fractures in anticoagulant users were compared using propensity score-weighted cumulative incidence differences (CIDs).

RESULTS

There were 23 515 patients identified (3241 apixaban users, 6867 dabigatran users, 3866 rivaroxaban users, and 9541 warfarin users). Overall mean age was 74.4 years (SD, 10.8), ranging from 73.1 years (warfarin) to 77.9 years (apixaban). Over a median follow-up of 423 days, 401 fractures were identified (crude event number [weighted rate per 100 patient-years]: apixaban, 53 [0.82]; dabigatran, 95 [0.76]; rivaroxaban, 57 [0.67]; and warfarin, 196 [1.11]). After 24-month follow-up, DOAC use was associated with a lower risk for fracture than warfarin use (apixaban CID, -0.88% [95% CI, -1.66% to -0.21%]; dabigatran CID, -0.81% [CI, -1.34% to -0.23%]; and rivaroxaban CID, -1.13% [CI, -1.67% to -0.53%]). No differences were seen in all head-to-head comparisons between DOACs at 24 months (apixaban vs. dabigatran CID, -0.06% [CI, -0.69% to 0.49%]; rivaroxaban vs. dabigatran CID, -0.32% [CI, -0.84% to 0.18%]; and rivaroxaban vs. apixaban CID, -0.25% [CI, -0.86% to 0.40%]).

LIMITATION

Residual confounding is possible.

CONCLUSION

Among patients with AF, DOAC use may result in a lower risk for osteoporotic fracture compared with warfarin use. Fracture risk does not seem to be altered by the choice of DOAC. These findings may help inform the benefit-risk assessment when choosing between anticoagulants.

PRIMARY FUNDING SOURCE

The University of Hong Kong and University College London Strategic Partnership Fund.

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.

The Impact of Regional Variation in Clinical Practice on Thyroid Cancer Diagnosis: A National Population-Based Study

OBJECTIVE

Regional variation in thyroid cancer incidence in Belgium, most pronounced for low risk cancer, was previously shown to be related to variation in clinical practice, with higher thyroid surgery rates and lower proportions of preoperative fine-needle aspiration (FNA) in regions with high thyroid cancer incidence (period 2004-2006). The objective of this study was to investigate regional thyroid cancer incidence variation in relation with variation in thyroid surgery threshold in a more recent Belgian thyroid cancer cohort.

METHODS

A population-based cohort of thyroid cancer patients that underwent a (near) total thyroidectomy in the period 2009-2011 (n = 2,329 patients) was identified and studied by linking data from the Belgian cancer registry and the Belgian health insurance companies, and case-by-case study of the pathology protocols. The execution of preoperative FNA and the thyroid resection specimen weight were compared between high and low thyroid cancer incidence regions. Thyroid weight in the pT1a-restricted group was studied as a proxy for surgical threshold for benign nodular goiter. Furthermore, time trend analyses were performed for the execution of FNA for the period 2004-2012.

RESULTS

Although a lower proportion of FNA in the high thyroid cancer incidence region persisted in the period 2009-2011 (41.2% [31.9-50.9] vs. 72.9% [64.9-79.7] in the low-incidence region (LIR), p < 0.001), a positive time trend was observed for the period 2004-2012. The median thyroid surgical specimen weight was lower in the high incidence region compared to the LIR (27.0 g [IQR 18.0-45.3] vs. 36.0 g [IQR 22.0-73.0], p < 0.0001), and this finding was corroborated in the pT1a-restricted group.

CONCLUSION

Interregional differences in use of FNA and surgical thyroid specimen weight are consistent with an inverse relation between thyroid cancer incidence and thyroid surgery threshold, carrying risk for overdiagnosis.

Flemish breast cancer screening programme: 15 years of key performance indicators (2002-2016)

Background

We examined 15 years of key performance indicators (KPIs) of the population-based mammography screening programme (PMSP) in Flanders, Belgium.

Methods

Individual screening data were linked to the national cancer registry to obtain oncological follow-up. We benchmarked crude KPI results against KPI-targets set by the European guidelines and KPI results of other national screening programmes. Temporal trends were examined by plotting age-standardised KPIs against the year of screening and estimating the Average Annual Percentage Change (AAPC).

Results

PMSP coverage increased significantly over the period of 15 years (+ 7.5% AAPC), but the increase fell to + 1.6% after invitation coverage was maximised. In 2016, PMSP coverage was at 50.0% and opportunistic coverage was at 14.1%, resulting in a total coverage by screening of 64.2%. The response to the invitations was 49.8% in 2016, without a trend. Recall rate decreased significantly (AAPC -1.5% & -5.0% in initial and subsequent regular screenings respectively) while cancer detection remained stable (AAPC 0.0%). The result was an increased positive predictive value (AAPC + 3.8%). Overall programme sensitivity was stable and was at 65.1% in 2014.

In initial screens of 2015, the proportion of DCIS, tumours stage II+, and node negative invasive cancers was 18.2, 31.2, and 61.6% respectively. In subsequent regular screens of 2015, those proportions were 14.0, 24.8, and 65.4% respectively. Trends were not significant.

Conclusion

Besides a suboptimal attendance rate, most KPIs in the Flemish PMSP meet EU benchmark targets. Nonetheless, there are several priorities for further investigation such as a critical evaluation of strategies to increase screening participation, organising a biennial radiological review of interval cancers, analysing the effect that preceding opportunistic screening has on the KPI for initial screenings, and efforts to estimate the impact on breast cancer mortality.

Breast cancer by migrant background in Belgium: Lower risk, but worse survival in women of non-European origin

Foreign and native populations differ in terms of breast cancer outcomes. Studies rarely distinguish between premenopausal and postmenopausal breast cancer, although the risk profile is different; nor between migrants of the first and second generation (FG and SG), which is crucial to examine genetic and environmental influences on breast cancer. This research fills these gaps by investigating patterns in breast cancer incidence and survival in different migrant groups by menopausal and migrant generational status, taking various risk factors into account. To this end, individually linked data from the 2001 census, the Belgian Cancer Registry and the Crossroads Bank for Social Security are used. Age-standardised incidence rates and incidence rate ratios are calculated by migrant background group, stratified according to ages 30-50 (premenopausal) and 50-70 (postmenopausal). Incidence rate ratios are examined with and without taking reproductive factors and socioeconomic position (SEP) into account. Relative survival percentages and relative excess risks of dying among premenopausal and postmenopausal patients are computed with and without controlling for the stage at diagnosis and SEP. Premenopausal breast cancer is further examined by migrant generational status. Breast cancer incidence is lower among non-European migrants compared to Belgians. Keeping SEP and known risk factors constant reduces much, but not all of the observed discrepancies. A risk convergence between SG migrants and Belgians for the development of premenopausal breast cancer is observed. Premenopausal breast cancer survival is worse among Moroccan patients due to a higher stage at diagnosis. This disadvantage is concentrated in the FG.

Head and Neck Cancer in Belgium: Quality of Diagnostic Management and Variability Across Belgian Hospitals Between 2009 and 2014

Aims: The study assessed the quality of diagnosis and staging offered to patients with a head and neck squamous cell carcinoma (HNSCC) and the variability across Belgian hospitals. Methods: In total, 9,245 patients diagnosed with HNSCC between 2009 and 2014, were identified in the population-based Belgian Cancer Registry (BCR). The BCR data were coupled with other databases providing information on diagnostic and therapeutic procedures reimbursed by the compulsory health insurance, vital status data, and comorbidities. The use of diagnosis and staging procedures was assessed by four quality indicators (QI) (i.e., use of dedicated head and neck imaging studies, use of PET-CT, TNM reporting and interval between diagnosis and start of treatment), for which a target was defined before the analysis. The association between the binary QIs and observed survival was assessed using Cox proportional hazard models adjusted for potential confounders. Results: Overall, 82.5% of patients received staging by MRI and/or CT of the head and neck region before the start of treatment. In 47.6% of stage III-IV patients eligible for treatment with curative intent, a whole-body FDG-PET(/CT) was performed. The proportion of patients whose cTNM and pTNM stage was reported to the BCR was 80.5 and 78.4%, respectively. The median interval from diagnosis to first treatment with curative intent was 32 days (IQR: 19-46). For none of these QIs the pre-set targets were reached and a substantial variability between centers was observed for all quality indicators. No binary QI was significantly associated with observed survival. Conclusions: The four quality indicators related to diagnosis and staging in HNSCC all showed substantial room for improvement. For none of them the pre-set targets were met at the national level and the variability between centers was substantial. Each Belgian hospital received an individual feedback report in order to stimulate reflection and quality improvement processes.

Beta-blocker use and mortality following ovarian cancer diagnosis: a population-based study

BACKGROUND

Preclinical studies suggest that β-blockers could exhibit anticancer properties in ovarian cancer. Similar effects have also been reported in observational studies, but their results remain inconsistent and could be impaired by methodological limitations. This study aimed to investigate whether β-blocker use is associated with improved survival in ovarian cancer patients at the Belgian population level.

METHODS

We conducted a population-based study by linking data of the Belgian Cancer Registry with medical claims data of the health insurance companies for patients diagnosed with ovarian cancer between 2004 and 2014. Information on ovarian-cancer-specific deaths was retrieved from mortality records collected by regional governments. Use of β-blockers was modelled as a time-varying covariate in Cox regression models to calculate adjusted hazards ratios (HRs) and 95% confidence intervals (95%CIs) for the association between postdiagnostic β-blocker exposure and overall or cancer-specific survival (OS and CSS, respectively). Adjustments were made for age at diagnosis, year of diagnosis, comorbidities, cancer stage, and cancer treatments.

RESULTS

In our population of 6197 patients, 2373 patients (38%) had at least one prescription of β-blockers in the 5 years following diagnosis. Postdiagnostic exposure to β-blockers was associated with a significant decrease in OS (adjusted HR, 1.21; 95%CI 1.12;1.30; p < 0.001) and CSS (adjusted HR, 1.17; 95%CI 1.07;1.29; p < 0.001). Moreover, this association remained similar in dose-response analyses, in subgroup analyses (including by β-blocker selectivity types), and in sensitivity analyses.

CONCLUSION

In this large nationwide cohort of ovarian cancer patients, β-blocker users had reduced survival.

The Belgian Virtual Tumorbank: A Tool for Translational Cancer Research

Background: Biobanks play a critical role in cancer research by providing high quality biological samples for research. However, the availability of tumor samples in single research institutions is often limited, especially for rare cancers. In order to facilitate the search for samples scattered among different Belgian institutions, a nationwide virtual tumorbank project was launched and is operational since February 2012. The Belgian Virtual Tumorbank (BVT) network encompasses the tumor biobanks from eleven Belgian university hospitals that collect and store residual human tumor samples locally and is coordinated by the Belgian Cancer Registry. Materials and Methods: A web application was developed and consists of two modules. The registration module (BVTr) centralizes the tumor sample data from the local partner biobanks. The catalog module (BVTc) allows researchers to trace the tumor samples in the 11 tumor biobanks. The BVTc contains patient, medical and technical data, but excludes identifying information to ensure privacy of individuals. Automatic and manual controls guarantee high quality data on the samples requested by scientists for research purposes in oncology. A major advantage of the BVT network is that the available data can be linked to the data of the Belgian Cancer Registry for quality control purposes. Results: Currently, more than 92,000 registrations are available in the catalog. Twenty-seven percent of the residual primary tumor samples originate from breast tissue, but also less frequent localisations such as head and neck (4%), male genital organs (1.7%), and urinary tract (1%) are available. In addition to the residual tumor tissue samples, also other available material can be stored and registered by the local biobanks. The most common type is corresponding normal tissue (19%).Other frequently available materials are plasma, blood, serum, DNA, and buffy coat. Even PBMCs, RNA, cytology, and urine are available in some cases. Discussion and Conclusion: The BVT catalog is a valuable source of information for oncology research and the ultimate goal is to promote multidisciplinary cancer research (i.e., pathogenesis, disease prediction, prevention, diagnosis, treatment, and prognosis) for the benefit of all cancer patients.

Statin use after diagnosis is associated with an increased survival in esophageal cancer patients: a Belgian population-based study

PURPOSE

Preclinical studies have shown that statins reduce proliferation in esophageal cancer. Three recent observational studies have shown encouraging results but suffered from limitations. This work aimed to assess at the Belgian population level whether statin usage was associated with a decreased mortality in esophageal cancer patients.

METHODS

We conducted an observational, population-based study by linking data of the Belgian Cancer Registry (BCR) with medical claims data coming from health insurance companies and mortality records collected by regional governments for patients diagnosed with esophageal cancer between 2004 and 2014. Using time-dependent Cox regression models, hazard ratios (HRs) and 95% confidence intervals (CI) for overall and cancer-specific mortality were calculated.

RESULTS

Of 6,238 patients with stage I-III esophageal cancer, post-diagnostic use of statins was found in 1,628 (26%) patients. Statins use after diagnosis was associated with a reduction in overall mortality (adjusted HR = 0.84, 95% CI [0.77; 0.92]) and cancer-specific mortality (adjusted HR = 0.87, 95% CI [0.78; 0.97]). Similar association were also seen for pre-diagnostic statin use in overall (adjusted HR = 0.83, 95% CI [0.76-0.91]) and cancer-specific analysis (adjusted HR = 0.86, 95% CI [0.77-0.96]).

CONCLUSIONS

In this large cohort of Belgian patients with esophageal cancer, statins use after diagnosis was associated with a decreased mortality.

North European comparison of treatment strategy and survival in older patients with resectable gastric cancer: A EURECCA upper gastrointestinal group analysis

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, cN0-2, 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 III 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.

International comparison of treatment strategy and survival in metastatic gastric cancer

Background

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.

Methods

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.

Results

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.

Conclusion

There is variation in the use of gastrectomy and chemotherapy in patients with metastatic gastric cancer, and subsequent differences in survival.

Later Stage Disease and Earlier Onset of Rectal Cancer: Epidemiology and Outcomes Comparison of Rectal Cancer in a Rural Appalachian Area to State and National Rates

Although the overall rate of colorectal cancer (CRC) has remained stable, studies have shown an increase in the rate of CRC in young patients (<50) nationwide. We hypothesize that the rectal cancer (RC) rate in young people has increased in rural Appalachia. The goal is to provide insight into the future of RC epidemiology in underserved populations. This Institutional Review Board–approved retrospective study evaluated RC patients diagnosed in 2003 to 2016, and compared the ratio of early-onset RC to the state and national ratios using West Virginia State Cancer Registry, North American Association of Central Cancer Registries (NAACCR) and Surveillance, Epidemiology, and End Results Program Database. Demographics include age, gender, ethnicity, and county. We also evaluated cancer stage, family history, and comorbidities, including body mass index, smoking, and alcohol history. The rate of early-onset RC in our area is 1.5 times higher than the national rates. In our population, 100 per cent of patients were white with an equal gender distribution. Young patients with RC were noted to be more overweight than national rates. Young RC patients are more likely to have a first- or second-degree relative with cancer diagnosis. Smoking was strongly associated with young RC. Compared with national statistics, a higher proportion of young patients had Stage 1 or 2 disease which correlated with better survival. The rate of early-onset RC in the Tristate Appalachian area in West Virginia is higher than the national rate with risk factors including white ethnicity, obesity, diabetes mellitus, smoking, family history, and history of pelvic surgeries. It warrants further investigation and discussion of current CRC screening guidelines that begin at age 50.

Breast cancer risk is increased in the years following false-positive breast cancer screening

Supplemental Digital Content is available in the text.

A small number of studies have investigated breast cancer (BC) risk among women with a history of false-positive recall (FPR) in BC screening, but none of them has used time-to-event analysis while at the same time quantifying the effect of false-negative diagnostic assessment (FNDA). FNDA occurs when screening detects BC, but this BC is missed on diagnostic assessment (DA). As a result of FNDA, screenings that detected cancer are incorrectly classified as FPR. Our study linked data recorded in the Flemish BC screening program (women aged 50–69 years) to data from the national cancer registry. We used Cox proportional hazards models on a retrospective cohort of 298 738 women to assess the association between FPR and subsequent BC, while adjusting for potential confounders. The mean follow-up was 6.9 years. Compared with women without recall, women with a history of FPR were at an increased risk of developing BC [hazard ratio=2.10 (95% confidence interval: 1.92–2.31)]. However, 22% of BC after FPR was due to FNDA. The hazard ratio dropped to 1.69 (95% confidence interval: 1.52–1.87) when FNDA was excluded. Women with FPR have a subsequently increased BC risk compared with women without recall. The risk is higher for women who have a FPR BI-RADS 4 or 5 compared with FPR BI-RADS 3. There is room for improvement of diagnostic assessment: 41% of the excess risk is explained by FNDA after baseline screening.

Assessing factors associated with long-term work disability after cancer in Belgium: a population-based cohort study using competing risks analysis with a 7-year follow-up

OBJECTIVES

The number of workers with cancer has dramatically increasing worldwide. One of the main priorities is to preserve their quality of life and the sustainability of social security systems. We have carried out this study to assess factors associated with the ability to work after cancer. Such insight should help with the planning of rehabilitation needs and tailored programmes.

PARTICIPANTS

We conducted this register-based cohort study using individual data from the Belgian Disability Insurance. Data on 15 543 socially insured Belgian people who entered into the long-term work disability between 2007 and 2011 due to cancer were used.

PRIMARY AND SECONDARY OUTCOME MEASURES

We estimated the duration of work disability using Kaplan-Meier and the cause-specific cumulative incidence of ability to work stratified by age, gender, occupational class and year of entering the work disability system for 11 cancer sites using the Fine and Gray model allowing for competing risks.

RESULTS

The overall median time of work disability was 1.59 years (95% CI 1.52 to 1.66), ranging from 0.75 to 4.98 years. By the end of follow-up, more than one-third of the disabled cancer survivors were able to work (35%). While a large proportion of the women were able to work at the end of follow-up, the men who were able to work could do so sooner. Being women, white collar, young and having haematological, male genital or breast cancers were factors with the bestlikelihood to be able to return to work.

CONCLUSION

Good prognostic factors for the ability to work were youth, woman, white collar and having breast, male genital or haematological cancers. Reviewing our results together with the cancer incidence predictions up to 2025 offers a high value for social security and rehabilitation planning and for ascertaining patients' perspectives.

Statin use is associated with improved survival in ovarian cancer: A retrospective population-based study

Background

Preclinical in vitro and in vivo studies suggest that statins could exhibit anticancer properties in ovarian cancer. Similar effects have also been reported in observational studies but their results remain inconsistent and could be impaired by methodological limitations. This study aimed to investigate whether statin use is associated with improved survival in ovarian cancer patients at the Belgian population-level.

Methods

All patients with invasive epithelial ovarian cancer diagnosed between 2004 and 2012 were identified from the Belgian Cancer Registry. Vital statuses were obtained from the Crossroads Bank for Social Security and ovarian cancer-specific deaths were identified from death certificates provided by regional administrations. Information on cancer treatments and statin use were retrieved from health insurance databases. Statin use was modelled as a time-varying covariate in Cox regression models to calculate adjusted hazards ratios (HR) and 95% confidence intervals (95%CI) for the association between postdiagnostic exposure to statins and overall- or ovarian cancer-specific mortality within three years after diagnosis. Adjustments were made for age at diagnosis, year of diagnosis, comorbidities, cancer stage, and cancer treatments.

Results

A total of 5,416 patients with epithelial ovarian cancer met the inclusion criteria. Of these 1,255 (23%) had at least one statin prescription within three years after diagnosis. Postdiagnostic use of statins was associated with a reduced risk of overall mortality (adjusted HR = 0.81, 95%CI:0.72–0.90, p<0.001). In analyses by statin type, this association was only significant for simvastatin (adjusted HR = 0.86, 95%CI:0.74–0.99, p = 0.05) or rosuvastatin (adjusted HR = 0.71, 95%CI:0.55–0.92, p = 0.01). In subgroup analyses by statin prediagnostic use, the protective association for postdiagnostic statin use was only observed in patients who were also using statins before diagnosis (adjusted HR = 0.73, 95%CI:0.64–0.83, p<0.001). Similar results were observed for ovarian cancer-specific mortality.

Conclusion

In this large nation-wide cohort of ovarian cancer patients postdiagnostic use of statins was associated with improved survival.

Patterns of care for non-small cell lung cancer patients in Belgium: A population-based study

Guidelines recommend surgery for Stage I-II, chemoradiation for Stage III and systemic therapy for Stage IV non-small cell lung cancer (NSCLC). However, patient related factors and patient preferences influence treatment decisions. We investigated patterns of care for Belgian NSCLC patients in 2010-2011, based on population-based data from the Belgian Cancer Registry and administrative databases. The relationship between patient characteristics, institutional diagnostic volume, type of treatment and survival was investigated. Overall, 20.8% of patients received no oncological treatment. 59% and 22.1% of Stage I-II patients received primary surgery or (chemo)radiation respectively. 34% of Stage III patients received chemoradiation and 17% of Stage IIIA patients had surgery. 70% of Stage IV patients received chemotherapy or targeted therapy. Moderate variability between centres was observed. For Stage IV, systemic therapy was less frequently used in higher volume centres and 1-year survival was lower in centres that had ≥ 50 new patients yearly. Although not all NSCLC patients received treatment as ideally recommended by guidelines, these results do not necessarily represent poor quality of care as patient characteristics and preferences need to be taken into account. Treatment options targeted towards patients with co-morbidity or unfit patients is warranted to improve outcomes of all NSCLC patients.

Epidemiology of basal and squamous cell carcinoma in Belgium: the need for a uniform and compulsory registration

BACKGROUND

Non-melanoma skin cancer (NMSC) is the most common type of cancer among Caucasians, however, few data exist on its incidence. Because of a sheer volume of these tumours, NMSC is often not systematically registered.

OBJECTIVE

To describe and analyse the incidence of basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) in Belgium.

METHODS

Incidence data of BCC and SCC, including multiple primary skin tumours in the same patient, were extracted from the Belgian Cancer Registry from 2004 to 2012 (predominantly coming from pathology notifications). Belgian legislation makes cancer registration compulsory for oncological care programmes and for all pathological anatomy laboratories.

RESULTS

Between 2004 and 2012, 113 254 BCC and 33 153 SCC cases were reported in Belgium. A total of 130 339 patients had 146 407 tumours. Approximately, 10% of the patients (12 759 patients) had multiple tumours. The world age-standardised incidence rate (WSR) for BCC increased from 36.9 in 2004 to 98.4 per 100 000 person years in 2012 for males and from 34.2 in 2004 to 102.0 in 2012 for females. For SCC, the WSR increased from 14.9 in 2004 to 24.7 in 2012 for males and from 6.8 in 2004 to 13.5 in 2012 for females.

CONCLUSIONS

From 2004 to 2012, the incidence of BCC and SCC markedly rose in Belgium, as also seen worldwide. Known causes are increased sun exposure caused by changed sunlight-related behaviour (increased outdoor activities and holidays, use of tanning beds and changes in clothing style), ageing and improved registration. Because of their high and increasing incidence, these cancers will have major implications on healthcare planning and preventive measures. Therefore, we recommend compulsory registration, whenever is possible, of BCC and SCC, although it is an ambitious objective, especially in countries with a high burden of these tumours and in countries where registration is currently unavailable.

Seasonal variation in cutaneous melanoma incidence, link with recent UV levels: a population-based study in Belgium (2006-2011)

Our objective was to test the hypothesis of a short-term late-promoting effect of ultraviolet (UV) exposure on the development of cutaneous melanoma as an explanation for the summer peak in melanoma incidence. Therefore, we studied seasonal variation in melanoma incidence in relation to recent UV levels by direct UV measurements. Data from the Belgian Cancer Registry on invasive cutaneous melanoma diagnosed during 2006-2011 were used for analysis. Daily data on UV measurements in Belgium were obtained from the Royal Meteorological Institute. Simple and multiple negative binomial regression models were used to investigate the influence of recent UV levels on melanoma incidence. The sum of the mean UV doses in the 2 months before diagnosis was used as a proxy for recent UV exposure in the population. To include variable sunburn risks during the year, the categorical variable 'semester' was created. The incidence of melanoma in Belgium shows a distinct seasonal variation, with peaks in June or July. We found that part of this variation could be explained by the variation in dermatologic activity and, therefore, used this as an offset in our models. We found a linear relationship between melanoma incidence and UV dose in the 2 months preceding the diagnosis. UV levels had more impact in the first semester. The effect of UV levels was not modified by sex nor age. The interaction between anatomical site and UV levels was significant (P=0.002) and showed a higher effect on the upper and lower limbs compared with the head and neck and trunk.

Regional Inequalities in Lung Cancer Mortality in Belgium at the Beginning of the 21st Century: The Contribution of Individual and Area-Level Socioeconomic Status and Industrial Exposure

Being a highly industrialized country with one of the highest male lung cancer mortality rates in Europe, Belgium is an interesting study area for lung cancer research. This study investigates geographical patterns in lung cancer mortality in Belgium. More specifically it probes into the contribution of individual as well as area-level characteristics to (sub-district patterns in) lung cancer mortality. Data from the 2001 census linked to register data from 2001-2011 are used, selecting all Belgian inhabitants aged 65+ at time of the census. Individual characteristics include education, housing status and home ownership. Urbanicity, unemployment rate, the percentage employed in mining and the percentage employed in other high-risk industries are included as sub-district characteristics. Regional variation in lung cancer mortality at sub-district level is estimated using directly age-standardized mortality rates. The association between lung cancer mortality and individual and area characteristics, and their impact on the variation of sub-district level is estimated using multilevel Poisson models. Significant sub-district variations in lung cancer mortality are observed. Individual characteristics explain a small share of this variation, while a large share is explained by sub-district characteristics. Individuals with a low socioeconomic status experience a higher lung cancer mortality risk. Among women, an association with lung cancer mortality is found for the sub-district characteristics urbanicity and unemployment rate, while for men lung cancer mortality was associated with the percentage employed in mining. Not just individual characteristics, but also area characteristics are thus important determinants of (regional differences in) lung cancer mortality.