Differences in the association of time to treatment initiation and survival according to various head and neck cancer sites in a nationwide cohort.

OBJECTIVES: To assess whether there are differences in the effects of time to treatment interval (TTI) on patient survival for head and neck cancer (HNC) sites in order to provide evidence that can support decision-making regarding prioritizing treatment. MATERIALS AND METHODS: Patients in the Netherlands with a first primary HNC without distant metastasis between 2010 and 2014 were included for analysis (N = 10,486). TTI was defined as the time from pathologic diagnosis to the start of initial treatment. Overall survival (OS), cox regression analyses and cubic spline hazard models were calculated and visualized. RESULTS: Overall, the hazard of dying was higher (HR = 1.003; 95 % CI 1.001-1.005) with each additional day until treatment initiation. The pattern, as visualized in cubic spline graphs, differed by site the hazard increased more steeply with increasing TTI for oral cavity cancer. For oropharyngeal and laryngeal cancer, a slight increase commenced after a longer TTI than for oral cavity cancer, while there was hardly an increase in hazard with increasing TTI for hypopharyngeal cancer. CONCLUSION: The relationship between longer TTI and decreased survival was confirmed, but slight variations in the pattern of the hazard of dying by TTI by tumour site were observed. These findings could support decisions on prioritizing treatment. However, other aspects such as extent of treatment and quality of life should be investigated further so this can also be included.

Swallowing after Oral Oncological Treatment: A Five-Year Prospective Study.

BACKGROUND: Swallowing rehabilitation in curative treated patients with oral cancer is still a challenge. Different factors may influence these patients' swallowing function. The aim of this study was to identify factors associated with swallowing function up to 5 years after cancer treatment. METHODS: Swallowing duration and frequency of 5 mL water and 15 mL applesauce were measured in 123 patients treated for oral cancer. Mixed model analyses were performed to identify associated factors. RESULTS: Age influenced all measured swallowing outcomes. Assessment moment, gender, tumor location, maximum tongue force, and tactile sensory function of the tongue were associated with both water and applesauce swallowing duration, tumor classification was associated with water swallowing duration, and alcohol consumption was associated with applesauce swallowing duration. Assessment moment, cancer treatment, maximum tongue force, and tactile sensory function of the tongue were associated with water and applesauce swallowing frequency. CONCLUSION: Patients who are older at diagnosis, women, and patients who regularly consume alcohol before their treatment may have poorer swallow functioning after curative oral cancer treatment. Patients that fit these criteria should have their swallowing evaluated during clinical follow-ups and sent to swallowing therapy when needed. During this therapy, optimizing tongue function needs attention to maintain an optimal swallowing function.

The solitary versus supported experience: Care inequality between rare and common cancer patients.

OBJECTIVE: Patients with a rare cancer (RC) often have a more complex disease trajectory than patients with a common cancer. Research involving both patient groups is needed to identify differences and resemblances. In this study, we aimed to explore and compare experiences, needs and quality of life of patients with rare and common cancer throughout the disease trajectory. METHODS: A qualitative focus group study was conducted, including patients with rare and common cancer (n = 25). Participants were purposively selected to reflect heterogeneity of cancer types. A semi-structured topic list was used. Focus groups (n = 4) were recorded, transcribed verbatim and analysed, using thematic analysis. RESULTS: Three themes were identified emphasizing care inequality between patients with rare and common cancer: (1) The solitary experience: lack of information and support impact the RC patient, (2) Sudden impact, but recognition reduces the common cancer burden, and (3) Absence of psychosocial care requires being empowered as a cancer patient. CONCLUSIONS: Patients with RC are faced with enormous challenges due to the high impact of their solitary experience on their quality of life, while patients with common cancer generally experience social support and recognition alleviating their burden. Centralisation of care for patients with RC is needed and tailored psychosocial care should be provided to overcome inequalities.

Number of life-years lost at the time of diagnosis and several years post-diagnosis in patients with solid malignancies: a population-based study in the Netherlands, 1989-2019.

Background: Loss of life expectancy (LOLE) may provide more intuitive information on the impact of cancer than relative survival over a fixed time horizon (e.g., 5-year relative survival). We aimed to assess the evolution of the LOLE using a nationwide, population-based cohort including patients diagnosed with one of 17 most frequent solid malignancies. Methods: From the Netherlands Cancer Registry, we selected adult patients diagnosed with one of the 17 most frequent solid malignancies in the Netherlands during 1989-2019, with survival follow-up until 2022. We used flexible parametric survival models to estimate the LOLE at diagnosis and the LOLE after surviving several years post-diagnosis (conditional LOLE; CLOLE) by cancer type, calendar year, age, sex, and disease stage. Findings: For all cancers combined, the LOLE consistently decreased from 1989 to 2019. This decrease was most pronounced for males with prostate cancer (e.g., from 6.9 [95% confidence interval [CI], 6.7-7.1] to 2.7 [95% CI, 2.5-3.0] for 65-year-olds) and females with breast cancer (e.g., from 6.6 [95% CI, 6.4-6.7] to 1.9 [95% CI, 1.8-2.0] for 65-year-olds). The LOLE among patients with cancers of the head and neck or the central nervous system remained constant over time. Overall, the CLOLE showed that the life years lost among patients with cancer decreased with each additional year survived post-diagnosis. For example, the LOLE at diagnosis for 65-year-old females diagnosed with breast cancer in 2019 was 1.9 [95% CI, 1.8-2.0] compared with 1.7 [95% CI, 1.6-1.8], 1.0 [95% CI, 0.9-1.1], and 0.5 [95% CI, 0.5-0.6] when surviving one, five, and ten years post-diagnosis, respectively. Estimates for other combinations of patient and tumour characteristics are available in a publicly available web-based application. Interpretation: Our findings suggested that the evolution of LOLE substantially varies across cancer type, age, and disease stage. LOLE estimates help patients better understand the impact of their specific cancer diagnosis on their life expectancy. Funding: None.

A nationwide study on cancer recurrences, second primary tumours, distant metastases and survival after treatment for primary head and neck cancer in the Netherlands.

INTRODUCTION: There is no consensus on the optimal duration of post-treatment follow-up after head and neck cancer (HNC). To generate site-specific input for follow-up guidelines, this study describes the incidence and timing of manifestations of disease during five years of follow-up. METHODS: All patients diagnosed with HNC in the Netherlands in 2015 were selected from the Netherlands Cancer Registry. The follow-up events local recurrence (LR), regional recurrence (RR), second primary tumour (SPT), distant metastasis (DM) and death were studied per follow-up-year. The cumulative incidence of these events was calculated using competing risk analyses, with LR, RR and SPT of the head and neck (SPHNC) as events and SPT outside the head-neck (SPOHN), DM and death as competing events. Analyses were performed for oral cavity-, oropharynx-, larynx- and hypopharynx squamous cell carcinoma (SCC), and all HNC patients. RESULTS: The 1-, 1.5-, and 2-year cumulative incidence of an event (LR, RR, SPHNC) were 10% (95%CI 8-13), 12% (95%CI 10-15), and 13% (95%CI 10-16) for oral cavity SCC; 6% (95%CI 4-9), 10% (95%CI 7-14), and 11% (95%CI 8-15) for oropharynx SCC; 7% (95%CI 5-10), 11% (95%CI 9-15), and 13% (95%CI 10-16) for larynx SCC and 11% (95%CI 6-19), 19% (95%CI 12-27), and 19% (95%CI 12-27) for hypopharynx SCC. CONCLUSIONS: One year of follow-up for oral cavity SCC, and 1.5 years for oropharynx-, larynx-, and hypopharynx SCC suffices for the goal of detecting disease manifestations after treatment. More research into other aspects of follow-up care should be performed to determine the optimal follow-up regimen.

A Systematic Review and Multilevel Regression Analysis Reveals the Comorbidity Prevalence in Cancer.

Comorbidities can have major implications for cancer care, as they might impact the timing of cancer diagnosis, compromise optimal care, affect treatment outcomes, and increase healthcare costs. Thus, it is important to comprehensively evaluate cancer comorbidities and examine trends over time. Here, we performed a systematic literature review on the prevalence and types of comorbidities for the five most common forms of cancer. Observational studies from Organisation for Economic Co-operation and Development countries published between 1990 and 2020 in English or Dutch that used routinely collected data from a representative population were included. The search yielded 3,070 articles, of which, 161 were eligible for data analyses. Multilevel analyses were performed to evaluate determinants of variation in comorbidity prevalence and trends over time. The weighted average comorbidity prevalence was 33.4%, and comorbidities were the most common in lung cancer (46.7%) and colorectal cancer (40.0%), followed by prostate cancer (28.5%), melanoma cancer (28.3%), and breast cancer (22.4%). The most common types of comorbidities were hypertension (29.7%), pulmonary diseases (15.9%), and diabetes (13.5%). After adjusting for gender, type of comorbidity index, age, data source (patient records vs. claims), and country, a significant increase in comorbidities of 0.54% per year was observed. Overall, a large and increasing proportion of the oncologic population is dealing with comorbidities, which could be used to inform and adapt treatment options to improve health outcomes and reduce healthcare costs. SIGNIFICANCE: Comorbidities are frequent and increasing in patients with cancer, emphasizing the importance of exploring optimal ways for uniform comorbidity registration and incorporating comorbidity management into cancer care.

Value of routine follow-up in oropharyngeal squamous cell cancer patients treated with curative intent.

BACKGROUND: The major goal of routine follow-up in oropharyngeal squamous cell carcinoma (OPSCC) patients is the asymptomatic detection of new disease in order to improve survival. This study evaluated the effect of routine follow-up on overall survival (OS). METHODS: A retrospective cohort of 307 consecutive OPSCC patients treated with curative intent between 2006 and 2012 was analyzed. The effectiveness of routine follow-up was studied by comparing treatment-intent and OS in patients with asymptomatically versus symptomatically detected new disease. RESULTS: Three- and five-year risks of new disease were 29% (95% CI: 24-34) and 33% (95% CI: 27-39). Of the 81 patients with locoregional recurrence or second primary head and neck cancer, 8 (10%) were detected asymptomatically with no difference in OS with those detected with symptoms. CONCLUSIONS: Asymptomatic detection of new disease during routine visits was not associated with improved OS. The focus of follow-up should be on providing psychosocial care and rehabilitation.

Cancer treatments touch a wide range of values that count for patients and other stakeholders: What are the implications for decision-making?

BACKGROUND: Cancer rates and expenditures are increasing, resulting in debates on the exact value of this care. Perspectives on what exactly constitutes worthwhile values differ. This study aims to explore all values-elements regarding new oncological treatments for patients with cancer and all stakeholders involved and to assess their implications in different decision-making procedures. METHOD: Thirty-one individual in-depth interviews were conducted with different stakeholders to identify values within oncology. A focus group with seven experts was performed to explore its possible implications in decision-making procedures. RESULTS: The overarching themes of values identified were impact on daily life and future, costs for patients and loved ones, quality of life, impact on loved ones, societal impact and quality of treatments. The expert panel revealed that the extended exploration of values that matter to patients is deemed useful in patient-level decision-making, information provision, patient empowerment and support during and after treatment. For national reimbursement decisions, implications for the broad range of values seems less clear. CONCLUSION: Clinical values are not the only ones that matter to oncological patients and the stakeholders in the field. We found a much broader range of values. Proper recognition of values that count might add to patient-level decision-making, but implications for reimbursement decisions are less clear. The results could be useful to guide clinicians and policymakers when it comes to decision-making in oncology. Making more explicit which values counts for whom guarantees a more systematic approach to decision-making on all levels.

RANKL inhibition for giant cell lesions of the jaw: A retrospective cohort analysis.

BACKGROUND: In all giant-cell-rich lesions (GCRL) occurring in bone, a common underlying excessive RANKL expression is held responsible for the osteolytic activity. Apart from giant cell tumour of bone (GCTB), systematic outcome analysis of RANKL inhibition in other GCRL is unavailable. The aim of this study is to assess the efficacy and safety of a 1-year denosumab protocol in giant cell lesions of the jaw (GCLJ). METHODS: A retrospective cohort study was conducted compromising patients treated with a 1-year protocol of monthly subcutaneously administered 120 mg denosumab. Objective tumour response based on histology and imaging was used to calculate objective tumour response rate, progression-free survival (PFS) and time to progression. Type, severity and frequency of adverse events were recorded in a standardised way to assess safety. RESULTS: Twenty patients, predominantly female (90%), were included. Fifty-five per cent of lesions were located in the mandible; most classified as aggressive lesions (90%). Thirty-five per cent (7/20) of cases were either recurrent after prior treatment or progressive, while on other drug treatment. Objective tumour response rate was 100% after 12 months of treatment. Median PFS was 50.4 months (95% CI 38.0-62.8) with a cumulative PFS rate of 22.6% (95% CI 1.8-43.4) at 5 years follow-up. Median time to progression was 38.4 months (95% CI 26.0-50.8). Treatment was well tolerated, and none of the patients had to interrupt therapy for toxicity. CONCLUSION: High-dose denosumab is effective and safe in achieving a complete response in GCLJ within 12 months. The high long-term relapse rate after treatment cessation is the main obstacle for denosumab to become standard treatment for GCLJ.

The gap between rare and common cancers still exists: Results from a population-based study in the Netherlands.

INTRODUCTION: Epidemiological discrepancies exist between rare and common cancers. The aim of this population-based study was to compare rare versus common adult solid cancers in the Netherlands, by providing incidence, prevalence and survival rates, evaluating trends in survival and comparing individual entities within domains and families. METHODS: All adult patients with malignant solid cancers in the Netherlands between 1995 and 2019 were identified from the Netherlands Cancer Registry. Data on patient, tumour and treatment characteristics were collected, and relative survival and survival trends were analysed. RESULTS: A total of 170,628 patients with rare adult solid cancers and 806,023 patients with common adult solid cancers were included. Rare cancers accounted for 18% of all cancer diagnoses (mean incidence), and 15% of the total ten-year cancer prevalence during 2010-2019. Overall 5-year survival was worse for rare cancers than for common cancers (52.0% versus 68.7%). Between 1995-1999 and 2015-2019, 5-year survival rates for rare cancers increased to a lesser extent (from 46.2% to 52.6%, i.e. 6.4%) than for common cancers (56.9%-70.1%, i.e. 13.2%), and for most rare cancer domains compared to common cancer domains. The majority of rare cancer entities did not show an improvement in 5-year survival. Differences for individual entities between domains and families were found. CONCLUSION: Differences in survival between rare and common cancers indicate major challenges for rare cancer care and emphasise that improvement is highly needed. Observed inequalities need to be overcome by investing in early diagnosis, novel therapies, scientific research and in establishing centres of expertise.

Fewer head and neck cancer diagnoses and faster treatment initiation during COVID-19 in 2020: A nationwide population-based analysis.

BACKGROUND: Inevitably, the emergence of COVID-19 has impacted non-COVID care. Because timely diagnosis and treatment are essential, especially for patients with head and neck cancer (HNC) with fast-growing tumours in a functionally and aesthetically important area, we wished to quantify the impact of the COVID-19 pandemic on HNC care in the Netherlands. MATERIAL AND METHODS: This population-based study covered all, in total 8468, newly diagnosed primary HNC cases in the Netherlands in 2018, 2019 and 2020. We compared incidence, patient and tumour characteristics, primary treatment characteristics, and time-to-treatment in the first COVID-19 year 2020 with corresponding periods in 2018 and 2019 (i.e. pre-COVID). RESULTS: The incidence of HNC was nearly 25% less during the first wave (n = 433) than in 2019 (n = 595) and 2018 (n = 598). In April and May 2020, the incidence of oral cavity and laryngeal carcinomas was significantly lower than in pre-COVID years. There were no shifts in tumour stage or alterations in initial treatment modalities. Regardless of the first treatment modality and specific period, the median number of days between first visit to a HNC centre and start of treatment was significantly shorter during the COVID-19 year (26-28 days) than pre-COVID (31-32 days, p < 0.001). CONCLUSION: The incidence of HNC during the Netherlands' first COVID-19 wave was significantly lower than expected. The expected increase in incidence during the remainder of 2020 was not observed. Despite the overloaded healthcare system, the standard treatment for HNC patients could be delivered within a shorter time interval.

Hyperbaric oxygen treatment of mandibular osteoradionecrosis: Combined data from the two randomized clinical trials DAHANCA-21 and NWHHT2009-1.

PURPOSE: Osteoradionecrosis (ORN) of the mandible is a serious complication of head and neck radiotherapy. This study aims to investigate the effect of hyperbaric oxygen (HBO) treatment on ORN in two randomized, controlled multicentre trials. METHODS AND MATERIALS: Patients with ORN with indication for surgical treatment were randomised to either group 1: surgical removal of necrotic mandibular bone supplemented by 30 pre- and 10 postoperative HBO exposures at 243 kPa for 90 min each, or group 2: surgical removal of necrotic bone only. Primary outcome was healing of ORN one year after surgery evaluated by a clinically adjusted version of the Common Toxicity Criteria of Adverse Events (CTCAE) v 3.0. Secondary outcomes included xerostomia, unstimulated and stimulated whole salivation rates, trismus, dysphagia, pain, Activities of Daily Living (ADL) and quality of life according to EORTC. Data were combined from two separate trials. Ninety-seven were enrolled and 65 were eligible for the intent-to-treat analysis. The 33% drop-out was equally distributed between groups. RESULTS: In group 1, 70% (21/30) healed compared to 51% (18/35) in group 2. HBO was associated with an increased chance of healing independent of baseline ORN grade or smoking status as well as improved xerostomia, unstimulated whole salivary flow rate, and dysphagia. Due to insufficient recruitment, none of the endpoints reached a statistically significant difference between groups. ADL data could only be obtained from 50 patients. CONCLUSION: Hyperbaric oxygen did not significantly improve the healing outcome of osteoradionecrosis after surgical removal of necrotic bone as compared to standard care (70% vs. 51%). This effect is not statistically significant due to the fact that the study was underpowered and is therefore prone to type II error.

Effect of elective neck dissection versus sentinel lymph node biopsy on shoulder morbidity and health-related quality of life in patients with oral cavity cancer: A longitudinal comparative cohort study.

OBJECTIVE: To research the difference in shoulder morbidity and health-related quality of life between patients with cT1-2N0 oral cavity squamous cell carcinoma that undergo either elective neck dissection (END) or a sentinel lymph node biopsy (SLNB) based approach of the neck. MATERIALS AND METHODS: A longitudinal study with measurements before surgery, 6 weeks, 6 months, and 12 months after surgery. Shoulder morbidity were determined with measurements of active range of motion of the shoulder and patient-reported outcomes for shoulder morbidity (SDQ, SPADI) and health-related quality of life (HR-QoL) (EQ5D, EORTC-QLQ-HN35). Linear mixed model analyses were used to analyze differences over time between patients that had END, SLNB or SLNB followed by complementing neck dissection. RESULTS: We included 69 patients. Thirty-three patients were treated with END. Twenty-seven patients had SLNB without complementing neck dissection (SLNB), and nine were diagnosed lymph node positive followed by completion neck dissection (SLNB + ND). Ipsilateral shoulder abduction (P = .031) and forward flexion (P = .039) were significantly better for the SLNB group at 6 weeks post-intervention compared to the END and SLNB + ND group. No significant differences for shoulder morbidity, or health-related quality of life were found at 6 weeks, 6 months, and 12 months between the three groups. CONCLUSION: With oncologic equivalence for the END and SLNB as strategies for the cN0 neck already demonstrated, and the SLNB being more cost-effective, our demonstrated benefit in short-term shoulder function strengthens the choice for the SLNB as a preferred treatment strategy.

Unmet supportive care needs of patients with rare cancer: A systematic review.

OBJECTIVE: Patients with rare cancers may experience different unmet needs than those with common cancer. The objective of this systematic review was to (1) investigate unmet supportive care needs of rare cancer patients throughout the disease trajectory and (2) identify predictive factors for these unmet needs. METHODS: PubMed, PsycINFO and CINAHL were searched for publications (January 2011 to March 2021) focusing on unmet needs of patients with rare cancer. Two reviewers independently selected studies, extracted data and performed quality assessment. Findings were synthesised. RESULTS: The search yielded 4,598 articles, of which 59 articles met eligibility criteria and 57 were of medium or high quality. Rare cancer patients most frequently reported unmet needs in the healthcare system and information domain (up to 95%), followed by the psychological domain (up to 93%) and the physical and daily living domain (up to 80%). Unmet needs were mainly reported in the posttreatment phase. The most frequently identified predictors were higher anxiety, younger age and higher neuroticism. CONCLUSION: Patients with rare cancer have unmet needs throughout their disease trajectory. Supportive care needs of rare cancer patients should be addressed individually, depending on the rare cancer subdomain and phase of disease and from diagnosis onwards.

Second primary tumours after squamous cell carcinoma of the oral cavity.

INTRODUCTION: The aim of this study was to determine the incidence, location and timing of second primary tumours (SPT) after diagnosis of oral squamous cell carcinoma (OSCC) and relate the risk of SPT to that after head and neck squamous cell carcinoma (HNSCC) and the risks of those tumours in the general population in order to assess the need for a separate follow-up programme for OSCC patients and to aid development of an evidence-based and individualized follow-up programme for OSCC patients. MATERIALS AND METHODS: All patients diagnosed with OSCC or HNSCC in the Netherlands in 1991-2015 were selected from the Netherlands Cancer Registry. Cumulative incidence rates and Standardized Incidence Ratios (SIR) were calculated. Analyses were stratified by incidence period and age at primary diagnosis of the index tumour, follow-up time, and site of the SPT. RESULTS: We included 11263 patients with OSCC from a population of 34244 patients with HNSCC, of which the median follow-up time was 4.0 years. OSCC SPT develop in different patterns and at different locations than after HNSCC. The 5-year risk of SPT and SIR (95% confidence intervals) were respectively 0.13 (0.13-0.14) and 3.0 (2.9-3.1) for OSCC. The risk of a SPT was continuous over follow-up time and calendar period but decreased with an increasing age at diagnosis of the index tumour up to the age of 75 and there were differences in sites of SPT. CONCLUSION: A specific follow-up protocol for OSCC is needed, which can be individualized on the basis of, among others, age.

Identifying unmet needs and limitations in physical health in survivors of Head and Neck Cancer.

OBJECTIVE: To gain insight into the level of unmet needs and limitations in physical health experienced by survivors of head and neck cancer, and to evaluate whether unmet needs in physical health and limitations in physical performance are associated. MATERIALS AND METHODS: In this cross-sectional study, unmet needs were measured with Supportive Care Needs Surveys (SCNS-SF34, SCNS-HNC). Limitations in physical health were measured for maximal mouth opening, neck and shoulder function, hand grip strength and lower body strength, level of mobility and walking ability. RESULTS: The SCNSs showed that 48% had a cancer generic unmet need and 46% had at least one HNC-specific unmet need. In total, 76% of sHNC had a cancer generic limitation in physical health and that 58% had an HNC-specific limitation in the mobility of neck and shoulders or maximum mouth opening. The domain of physical and daily living needs showed a weak association with lateral flexion of the neck to the left (R = -0.319; p = 0.024). CONCLUSION: Survivors of HNC might benefit from the use of both SCNSs and physical performance measurements during usual care follow-up for early and optimal identification of unmet needs and limitations in physical health.

Depression and related factors after oral oncological treatment: a 5-year prospective cohort study.

PURPOSES: Being diagnosed with oral cancer is a life-threatening life event. It often induces social, emotional and psychological consequences and may cause depressive disorders. The primary aim of this study was to identify and quantify the personal and clinical characteristics involved in depression for patients who have been treated for oral cavity malignancies, with a 5-year follow-up period after treatment. The secondary aim of this study was to identify the clinical factors that increase a patient's risk of experiencing depression 5 years after treatment. METHODS: Patients with primary oral cancer were assessed for up to 5 years after primary treatment. A mixed-model analysis was performed, with depression measured by the Center for Epidemiologic Studies Depression Scale as outcome measure. RESULTS: A total of 141 patients were included in the study. Factors associated with depression were gender, tumour location and having an emotion-oriented coping style. The occurrence of depression within 5 years after treatment could be reliably predicted by a patient's gender, the location of their tumour and the extent to which they had an emotion-oriented coping style. CONCLUSIONS: This study revealed that being female, having a maxillary tumour and having an emotion-oriented coping style are associated with higher levels of depressive symptoms in patients treated for oral cancer up to 5 years post-treatment. A substantial proportion of the patients with oral cancer experienced high levels of depression both before and after their treatment, suggesting that adequate diagnostics and care are needed to try to prevent severe depression in these patients.

The impact of the temporary suspension of national cancer screening programmes due to the COVID-19 epidemic on the diagnosis of breast and colorectal cancer in the Netherlands.

Oncological care was largely derailed due to the reprioritisation of health care services to handle the initial surge of COVID-19 patients adequately. Cancer screening programmes were no exception in this reprioritisation. They were temporarily halted in the Netherlands (1) to alleviate the pressure on health care services overwhelmed by the upsurge of COVID-19 patients, (2) to reallocate staff and personal protective equipment to support critical COVID-19 care, and (3) to mitigate the spread of COVID-19. Utilising data from the Netherlands Cancer Registry on provisional cancer diagnoses between 6 January 2020 and 4 October 2020, we assessed the impact of the temporary halt of national population screening programmes on the diagnosis of breast and colorectal cancer in the Netherlands. A dynamic harmonic regression model with ARIMA error components was applied to assess the observed versus expected number of cancer diagnoses per calendar week. Fewer diagnoses of breast and colorectal cancer were objectified amid the early stages of the initial COVID-19 outbreak in the Netherlands. This effect was most pronounced among the age groups eligible for cancer screening programmes, especially in breast cancer (age group 50-74 years). Encouragingly enough, the observed number of diagnoses ultimately reached and virtually remained at the level of the expected values. This finding, which emerged earlier in age groups not invited for cancer screening programmes, comes on account of the decreased demand for critical COVID-19 care since early April 2020, which, in turn, paved the way forward to resume screening programmes and a broad range of non-critical health care services, albeit with limited operating and workforce capacity. Collectively, transient changes in health-seeking behaviour, referral practices, and cancer screening programmes amid the early stages of the initial COVID-19 epidemic in the Netherlands conjointly acted as an accelerant for fewer breast and colorectal cancer diagnoses in age groups eligible for cancer screening programmes. Forthcoming research is warranted to assess whether the decreased diagnostic scrutiny of cancer during the COVID-19 pandemic resulted in stage migration and altered clinical management, as well as poorer outcomes.