(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.

Monitoring complications of colonoscopies after a positive faecal immunochemical test (FIT-colonoscopies) is crucial in FIT-based colorectal cancer (CRC) screening. We investigated the occurrence of bleeding and perforation post FIT-colonoscopies (2013–2019) in Flanders and the contributing factors. A retrospective case–control study was conducted, including bleeding/perforation cases within 14 days after index colonoscopy, and controls without such events. Bleeding rates dropped from 0.9–1.1% (pre-2017) to 0.3% (2017–2018) and further to 0.05% (2019), while perforation rates remained at 0.05–0.11% (2014–2019). Male gender, polypectomy, general anaesthesia, and recent antiplatelet/antithrombotic drug use increased bleeding odds. Incomplete colonoscopy, polypectomy, general anaesthesia, and recent antiplatelet/antithrombotic drug use raised perforation odds. The endoscopists (n = 16) with highest bleeding rates (top 5%) performed only 6% of total FIT-colonoscopies, yet their patients experienced 45.5% of bleeding events. Similarly, for the top 5% of perforation rates, endoscopists conducting only 4.5% of total FIT-colonoscopy had 49.0% of perforation events occur in their patients. This study sheds light on FIT-colonoscopy-related complications in Flanders, their rates and risk factors. These findings can be incorporated into CRC screening materials and guide interventions to mitigate complications. A central colonoscopy register is currently lacking in Belgium, highlighting the need for its establishment to facilitate recurrent monitoring and evaluation.

Background/Objectives: Melanoma is the most lethal cutaneous neoplasm, with Breslow thickness being a key prognostic factor. This retrospective cohort study aimed to assess the impact of screening frequency and diagnostic methods on tumour stage at diagnosis and to explore implications for risk-adapted strategies. Methods: Between 2017 and 2024, 475 cases of melanoma were diagnosed in 397 patients. Screening frequency, diagnostic method, and patient risk were analyzed in relation to tumour stage. Results: Compared with first-visit cases, patients who underwent screening within two years prior to diagnosis were more often diagnosed with melanoma in situ (32.6% vs. 44–51%; p < 0.05) and had thinner invasive tumours (0.68–0.73 mm vs. 1.8 mm; p ≤ 0.001), though no differences were seen between screening frequencies. Full-body examination was associated with more in situ melanomas (46% vs. 34%; p = 0.016) and thinner invasive tumours (0.92 vs. 2.05 mm; p = 0.2) compared with lesion-directed screening, but this effect disappeared after excluding first-visit cases. Invasive melanomas diagnosed by mole mapping were significantly thinner than by dermoscopy (0.55 vs. 1.07; p = 0.035). In high-risk patients, tumour thickness decreased with more frequent visits (0.905 mm without screening vs. 0.40–0.55 mm with ≥1 visit; p = 0.001). Moreover, mole mapping identified thinner melanomas in the high-risk group compared with dermoscopy (0.47 vs. 0.60 mm; p = 0.02). Conclusions: Screening is associated with thinner melanomas and more in situ diagnoses. Digital mole mapping offers additional benefits, with high-risk patients profiting most, while low-risk individuals could be managed with less resource-intensive approaches. These findings support risk-adapted screening strategies focusing on intensive, digitally supported modalities for high-risk groups.