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Childhood cancer survivors (CCS) require specialized follow-up throughout their lifespan to prevent or manage late effects of cancer treatment. Knowing the size and structure of the population of CCS is crucial to plan interventions. In this scoping review we reviewed studies that reported prevalence of CCS in Europe. We searched Medline, Web of Science, and Embase using permutations of terms referring to childhood, cancer, survivors, prevalence, registries, and Europe. We followed PRISMA-ScR guidelines to select studies and The Joanna Briggs Institute Prevalence Critical Appraisal Tool to evaluate their quality. From 979 unique studies published between 1989 and 2022, 12 were included. Limited-duration prevalence (LDP) for all childhood cancers, assessed in three studies using counting method, varied between 450 and 1240 persons per million. Complete prevalence (CP) of survivors of any childhood cancer except skin carcinomas, reported in three studies using observed data complemented with modelled data for the unobserved period, varied between 730 and 1110 persons per million. CP of survivors of an embryonal tumour was estimated by completeness index method in six studies. In four of them CP ranged from 48 to 95 persons per million for all embryonal tumours, while CP for those occurring in central nervous system was 43 per million in one study and CP for rhabdomyosarcoma was 17 per million in another. Information on prevalence of CCS in Europe is fragmented and inconsistent. The large variations in LDP and CP estimates were linked to differences in data availability, the selection of populations, prevalence measure, statistical method, incidence period, index date, age at diagnosis and prevalence, cancer types, sex, and, for LDP, also the length of follow-up. Standardisation of methodology and reporting are needed to systematically monitor and compare CCS prevalence in Europe and provide data to help address survivors' needs.
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HPV vaccination with concomitant HPV-based screening of young women has been proposed for faster cervical cancer elimination. We describe the baseline results of a population-based trial of this strategy to reduce the incidence of HPV. All 89,547 women born 1994-1999 and resident in the capital region of Sweden were personally invited to concomitant HPV vaccination and HPV screening with 26,125 women (29.2%) enrolled between 2021-05-03 and 2022-12-31. Baseline HPV genotyping of cervical samples from the study participants finds, compared to pre-vaccination prevalences, a strong decline of HPV16 and 18 in birth cohorts previously offered vaccination, some decline for cross-protected HPV types but no decline for HPV types not targeted by vaccines. Our dynamic transmission modelling predicts that the trial could reduce the incidence of high-risk HPV infections among the 1994-1998 cohorts by 62-64% in 3 years. Baseline results are prevalences of HPV infection, validated transmission model projections, and power estimates for evaluating HPV incidence reductions at follow-up (+/-0.1% with 99.9% confidence). In conclusion, concomitant HPV vaccination and HPV screening appears to be a realistic option for faster cervical cancer elimination. Clinicaltrials.gov identifier: NCT04910802; EudraCT number: 2020-001169-34.
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Infecções por Papillomavirus , Vacinas contra Papillomavirus , Neoplasias do Colo do Útero , Humanos , Feminino , Neoplasias do Colo do Útero/prevenção & controle , Neoplasias do Colo do Útero/virologia , Neoplasias do Colo do Útero/epidemiologia , Infecções por Papillomavirus/epidemiologia , Infecções por Papillomavirus/prevenção & controle , Infecções por Papillomavirus/virologia , Vacinas contra Papillomavirus/imunologia , Vacinas contra Papillomavirus/administração & dosagem , Vacinas contra Papillomavirus/uso terapêutico , Adulto , Suécia/epidemiologia , Adulto Jovem , Vacinação , Adolescente , Incidência , Programas de Rastreamento , Prevalência , Pessoa de Meia-Idade , Detecção Precoce de Câncer , Papillomavirus Humano 16/genética , Papillomavirus Humano 16/imunologia , Papillomavirus Humano 18/genética , Papillomavirus Humano 18/imunologia , Papillomavirus HumanoRESUMO
BACKGROUND: Estimating the number of childhood cancer survivors is crucial for cancer control, including clinical guidelines. To compare estimates across countries despite data sharing restrictions, we propose a new method of computing limited-duration prevalence of childhood cancer survivors (POCCS) using aggregated data. METHODS: We developed a Markov model that simulates, for each calendar year and birth cohort in a population, the proportion of individuals in the following health states: healthy, newly diagnosed with cancer, surviving with cancer, and deceased. Transitions between health states were informed using annual sex- and age-specific incidence rates, conditional 1-year net survival probabilities from the Netherlands Cancer Registry (1989-2011), and annual mortality probability by sex and age group for The Netherlands from the Human Mortality Database. Applying a Markov model, we computed 20-year prevalence of childhood cancer survivors. The resulting POCCS estimates, stratified by sex, were compared with SEER*Stat estimates derived from individual cancer records from the same registry. RESULTS: In 2011, POCCS predicted 654 males [95% confidence interval (95% CI): 637-672] and 539 females (95% CI: 523-555) per million persons living in The Netherlands after childhood cancer diagnosed within the previous 20 years. Using SEER*Stat, the 20-year prevalence was 665 males (95% CI: 647-683) and 544 females (95% CI: 529-560) per million persons on 1 July 2011. CONCLUSIONS: Using the POCCS model and aggregated cancer data, our estimates of childhood cancer survivors limited-duration prevalence were consistent with those computed by a standard method requiring individual cancer records. The POCCS method provides relevant information for planning follow-up and care for childhood cancer survivors.
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Sobreviventes de Câncer , Neoplasias , Masculino , Feminino , Criança , Humanos , Neoplasias/epidemiologia , Prevalência , Países Baixos/epidemiologia , IncidênciaRESUMO
Survivors of childhood cancer have an increased risk of long-term health issues arising mostly from the side effects of treatment. Using population-based data from the Australian Childhood Cancer Registry (ACCR) for children aged 0-14 at diagnosis between 1983 and 2018, there were a total of 17,468 prevalent cases of childhood cancer survivors on 31 December 2018. We also found an 80% increase in the number of 5-year prevalent cases, from 1979 in 1988 to 3566 in 2018. Both short- and long-term prevalence estimates are important for monitoring childhood cancer survivorship and planning for the specific needs of this expanding cohort.
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Sobreviventes de Câncer , Neoplasias , Humanos , Criança , Neoplasias/terapia , Austrália/epidemiologia , Prevalência , SobreviventesRESUMO
BACKGROUND: Hodgkin lymphoma survivors treated with infradiaphragmatic radiotherapy (IRT) and/or procarbazine have an increased risk of developing colorectal cancer. We investigated the cost-effectiveness of colorectal cancer surveillance in Dutch Hodgkin lymphoma survivors to determine the optimal surveillance strategy for different Hodgkin lymphoma subgroups. METHODS: The Microsimulation Screening Analysis-Colon model was adjusted to reflect colorectal cancer and other-cause mortality risk in Hodgkin lymphoma survivors. Ninety colorectal cancer surveillance strategies were evaluated varying in starting and stopping age, interval, and modality [colonoscopy, fecal immunochemical test (FIT, OC-Sensor; cutoffs: 10/20/47 µg Hb/g feces), and multi-target stool DNA test (Cologuard)]. Analyses were also stratified per primary treatment (IRT and procarbazine or procarbazine without IRT). Colorectal cancer deaths averted (compared with no surveillance) and incremental cost-effectiveness ratios (ICER) were primary outcomes. The optimal surveillance strategy was identified assuming a willingness-to-pay threshold of 20,000 per life-years gained (LYG). RESULTS: Overall, the optimal surveillance strategy was annual FIT (47 µg) from age 45 to 70 years, which might avert 70% of colorectal cancer deaths in Hodgkin lymphoma survivors (compared with no surveillance; ICER:18,000/LYG). The optimal surveillance strategy in Hodgkin lymphoma survivors treated with procarbazine without IRT was biennial FIT (47 µg) from age 45 to 70 years (colorectal cancer mortality averted 56%; ICER:15,000/LYG), and when treated with IRT and procarbazine, annual FIT (47 µg) surveillance from age 40 to 70 was most cost-effective (colorectal cancer mortality averted 75%; ICER:13,000/LYG). CONCLUSIONS: Colorectal cancer surveillance in Hodgkin lymphoma survivors is cost-effective and should commence earlier than screening occurs in population screening programs. For all subgroups, FIT surveillance was the most cost-effective strategy. IMPACT: Colorectal cancer surveillance should be implemented in Hodgkin lymphoma survivors.
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Neoplasias Colorretais , Doença de Hodgkin , Humanos , Pessoa de Meia-Idade , Idoso , Adulto , Análise Custo-Benefício , Doença de Hodgkin/tratamento farmacológico , Doença de Hodgkin/radioterapia , Procarbazina/uso terapêutico , Detecção Precoce de Câncer , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/diagnóstico , Sangue Oculto , Colonoscopia , SobreviventesRESUMO
Food webs studies are intrinsically complex and time-consuming. Network data about trophic interaction across different large locations and ecosystems are scarce in comparison with general ecological data, especially if we consider terrestrial habitats. Here we present a complex network strategy to ease the gathering of the information by simplifying the collection of data with a taxonomic key. We test how well the topology of three different food webs retain their structure at the resolution of the nodes across distinct levels of simplification, and we estimate how community detection could be impacted by this strategy. The first level of simplification retains most of the general topological indices; betweenness and trophic levels seem to be consistent and robust even at the higher levels of simplification. This result suggests that generalisation and standardisation, as a good practice in food webs science, could benefit the community, both increasing the amount of open data available and the comparison among them, thus providing support especially for scientists that are new in this field and for exploratory analysis.
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Ecossistema , Cadeia AlimentarRESUMO
Background: To examine global patterns of gastric cancer in 2020 and the projected burden in 2040. Methods: Data on primary gastric cancer were extracted from the GLOBOCAN database for the year 2020. Age-standardized incidence and mortality rates were calculated by sex, country, world region and level of human development index (HDI) for 185 countries. The predicted burden of incidence and mortality in 2040 was calculated based on demographic projections. Findings: In total, â¼1.1 million new cases and 770,000 deaths of gastric cancer were estimated in 2020. Incidence rates were on average 2-fold higher in males than females (15.8 and 7.0 per 100,000, respectively) with variation across countries. Highest incidence rates were observed in Eastern Asia for both males and females (32.5 and 13.2, respectively); males residing in Japan (48.1), Mongolia (47.2) and Korea (39.7) had the highest rates in the world. Incidence was lowest in Africa with incidence rates < 5 per 100,000. Highest mortality rates were observed in Eastern Asia for both males (21.1) and females (8.8). A lower share of deaths was observed in very high HDI countries compared to medium and low HDI countries. The annual burden of gastric cancer is predicted to increase to â¼1.8 million new cases and â¼1.3 million deaths by 2040. Interpretation: These estimates of the global burden of gastric cancer pinpoint countries and regions of high incidence and mortality in need of cancer control initiatives. Primary prevention through eradication of H. pylori and behavioural changes such as reducing salt intake, smoking, obesity, and alcohol, remains key in stomach cancer control. Funding: No direct funding was received. All authors had access to the included study data and all authors agreed with the final decision to submit for publication.
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A faecal immunochemical test (FIT) screening pilot was introduced in Finland in 2019 with sex-specific screening strategies. This study aims to model cost-effectiveness of sex-specific strategies for the whole population, and to assess whether the current strategies are optimal. We developed separate MISCAN-Colon models, including different FIT performances, for the Finnish men and women using the first-year data of the FIT screening pilot. We evaluated 180 FIT strategies varying in FIT cut-off, screening interval, age to start, and age to stop screening, and compared them to no-screening by sex. We used incremental cost-effectiveness ratios (ICERs) to identify the optimal strategy after combining all male and female strategies and restricting the analysis by costs and referral rate to diagnostic colonoscopies. Offering annual FIT screening with a cut-off of 25 µg/g at 50-79 years in men and with a cut-off of 10 µg/g at 55-69 years in women was optimal. This combined strategy prevented 28% of colorectal cancer (CRC) cases and 55% of CRC deaths with acceptable costs (ICER = 9000/life-years gained). Screening at the current target age of 60-74 years was suboptimal for both sexes. Among strategies with the same target age and interval for both sexes, expected benefits from optimal screening were lower but still reasonable. Our results support a wider age range of screening in men, and a lower cut-off for a positive test in women when restrictions on colonoscopy capacity and costs are in place. National FIT screening program should start at younger age.
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Neoplasias Colorretais , Detecção Precoce de Câncer , Idoso , Colonoscopia , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/prevenção & controle , Análise Custo-Benefício , Detecção Precoce de Câncer/métodos , Feminino , Finlândia , Humanos , Masculino , Programas de Rastreamento/métodos , Pessoa de Meia-Idade , Sangue OcultoRESUMO
Our study examines global patterns of Hodgkin lymphoma (HL) in 2020 and predicts the future incidence and mortality burden in 2040 using IARC's GLOBOCAN estimates of the number of new cases and deaths of HL in 185 countries. A total of 83 000 new cases of HL and 23 000 deaths from HL were estimated in 2020. In general, incidence and mortality rates were consistently higher in males (50% more cases and deaths than females) across world regions and countries. Incidence rates varied markedly by world region, at least 10-fold in both sexes, with the highest incidence rates observed in Southern Europe. Mortality exhibited an inverse pattern compared to incidence, with rates elevated in Western Asia and Northern Africa. The number of HL incident cases is predicted to rise to around 107 000 cases (a 30% increase) by 2040 due to demographic changes, assuming global rates in 2020 remains unchanged. The findings provide a baseline and impetus for developing strategies that aim to reduce the burden of HL in future decades.
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Doença de Hodgkin , Europa (Continente)/epidemiologia , Feminino , Previsões , Saúde Global , Doença de Hodgkin/epidemiologia , Humanos , Incidência , Masculino , MortalidadeRESUMO
The combination of catalysis and transport across lipid bilayer membranes promises directional access to a solvent-free and structured nanospace that could accelerate, modulate, and, at best, enable new chemical reactions. To elaborate on these expectations, anion transport and catalysis with pnictogen and tetrel bonds are combined with polyether cascade cyclizations into bioinspired cation transporters. Characterized separately, synergistic anion and cation transporters of very high activity are identified. Combined for catalysis in membranes, cascade cyclizations are found to occur with a formal rate enhancement beyond one million compared to bulk solution and product formation is detected in situ as an increase in transport activity. With this operational system in place, intriguing perspectives open up to exploit all aspects of this unique nanospace for important chemical transformations.
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Research on animal colouration has grown exponentially in the last decade thanks to multidisciplinary approaches. Most studies are focused on trade-offs between communication and mimicry, which represent the two main constraints and drivers of the evolution of body colourations. Reptiles are excellent model species for investigating this field of study and lizards in particular show great variability of body colourations and their functions. We studied the lizard Podarcis siculus, analysing the variations of dorsal colour of three populations and obtained clear patterns of seasonal and ontogenetical variation of dorsal colour. According to baseline colour, males were greener and brighter than females, although no difference in saturation was recorded. According to seasonal variations, analyses showed that both sexes significantly vary in colour over the year: males reached higher peaks of hue and saturation later than females during spring, while females showed higher peaks of brightness and reached earlier similarly to hue and saturation. Ontogenetic variations were recorded only in males, which become greener, less bright and saturated with growing size. Therefore, our results suggest the occurrence of two opposing strategies in colour expression between sexes: males' dorsal colouration plays a major role in communication, while females are more crypsis-oriented.
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Lagartos/fisiologia , Pigmentação/fisiologia , Fatores Sexuais , Animais , Feminino , Itália , Masculino , Estações do AnoRESUMO
BACKGROUND: Alongside the SARS-CoV-2 (COVID-19) pandemic, Brazil also faces an ongoing rise in cancer burden. In 2020, there were approximately 592 000 new cancer cases and 260 000 cancer deaths. Considering the heterogeneities across Brazil, this study aimed to estimate the impact of the COVID-19 pandemic on cancer-related hospital admissions at a national and regional level. METHODS: The national, regional, and state-specific monthly average of cancer-related hospital admission rates per 100 000 inhabitants and 95% confidence intervals (95% CIs) were calculated from March to July (2019: pre-COVID-19; and 2020: COVID-19 period). Thematic maps were constructed to compare the rates between periods and regions. RESULTS: Cancer-related hospital admissions were reduced by 26% and 28% for clinical and surgical purposes, respectively. In Brazil, the average hospitalization rates decreased from 13.9 in 2019 to 10.2 in 2020 per 100,000 inhabitants, representing a rate difference of -3.7 (per 100,000 inhabitants; 95% CI: -3.9 to -3.5) for cancer-related (clinical) hospital admissions. Surgical hospital admissions showed a rate decline of -5.8 per 100,000 (95% CI: -6.0 to -5.5). The reduction in cancer-related admissions for the surgical procedure varies across regions ranging between -2.2 and -10.8 per 100 000 inhabitants, with the most significant decrease observed in the south and southeastern Brazil. CONCLUSIONS: We observed a substantial decrease in cancer-related hospital admissions during the COVID-19 pandemic with marked differences across regions. Delays in treatment may negatively impact cancer survival in the future; hence, cancer control strategies to mitigate the impact are needed.
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COVID-19/prevenção & controle , Hospitalização/estatística & dados numéricos , Neoplasias/terapia , Admissão do Paciente/estatística & dados numéricos , Brasil/epidemiologia , COVID-19/epidemiologia , COVID-19/virologia , Geografia , Hospitalização/tendências , Humanos , Oncologia/estatística & dados numéricos , Neoplasias/diagnóstico , Pandemias , SARS-CoV-2/fisiologiaRESUMO
While the integration of supramolecular principles in catalysis attracts increasing attention, a direct comparative assessment of the resulting systems catalysts to work out distinct characteristics is often difficult. Herein is reported how the broad responsiveness of ether cyclizations to diverse inputs promises to fill this gap. Cyclizations in the confined, π-basic and Brønsted acidic interior of supramolecular capsules, for instance, are found to excel with speed (exceeding general Brønsted acid and hydrogen-bonding catalysts by far) and selective violations of the Baldwin rules (as extreme as the so far unique pnictogen-bonding catalysts). The complementary cyclization on π-acidic aromatic surfaces remains unique with regard to autocatalysis, which is shown to be chemo- and diastereoselective with regard to product-like co-catalysts but, so far, not enantioselective.
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Éter , Catálise , Ciclização , Ligação de HidrogênioRESUMO
BACKGROUND: Aiming to support European countries in improving their breast, cervical, and colorectal cancer (CRC) screening programmes, the EU-TOPIA consortium has developed an online user-friendly tool (the EU-TOPIA evaluation tool; https://miscan.eu-topia.org) based on the Microsimulation Screening Analysis (MISCAN) model. METHODS: We designed an online platform that allows stakeholders to use their country-specific data (demographic, epidemiological, and cancer screening information) to quantify future harms and benefits of different cancer screening scenarios in their country. Current cancer screening programmes and impacts of potential changes in screening protocols (such as extending target ages or increasing screening attendance) can be simulated. Results are scaled to the country-specific population. To illustrate the tool, we used the tool to simulate two different CRC screening scenarios in the Netherlands: biennial fecal immunochemical testing (FIT) in ages 55-75 and colonoscopy every ten years in ages 55-75. Data from the Dutch screening programme was used to inform both scenarios. RESULTS: A total of 482,700 CRC cases and 178,000 CRC deaths were estimated in the Netherlands with FIT screening (for individuals aged 40-100 years, 2018-2050), with 47.3 million FITs performed (1.92 million positives of which 1.64 million adhered to diagnostic colonoscopy). With colonoscopy screening, CRC incidence and mortality were, respectively, up to 17% and 14% lower than in the current FIT screening programme, requiring, however, a colonoscopy demand that was 7-fold higher. CONCLUSIONS: Our study presents an essential online tool for stakeholders and medical societies to quantify estimates of benefits and harms of early cancer detection in Europe.
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Background. Validated microsimulation models have been shown to be useful tools in providing support for colorectal cancer (CRC) screening decisions. Aiming to assist European countries in reducing CRC mortality, we developed and validated three regional models for evaluating CRC screening in Europe. Methods. Microsimulation Screening Analysis-Colon (MISCAN-Colon) model versions for Italy, Slovenia, and Finland were quantified using data from different national institutions. These models were validated against the best available evidence for the effectiveness of screening from their region (when available): the Screening for COlon REctum (SCORE) trial and the Florentine fecal immunochemical test (FIT) screening study for Italy; the Norwegian Colorectal Cancer Prevention (NORCCAP) trial and the guaiac fecal occult blood test (gFOBT) Finnish population-based study for Finland. When published evidence was not available (Slovenia), the model was validated using cancer registry data. Results. Our three models reproduced age-specific CRC incidence rates and stage distributions in the prescreening period. Moreover, the Italian and Finnish models replicated CRC mortality reductions (reasonably) well against the best available evidence. CRC mortality reductions were predicted slightly larger than those observed (except for the Florentine FIT study), but consistently within the corresponding 95% confidence intervals. Conclusions. Our findings corroborate the MISCAN-Colon reliability in supporting decision making on CRC screening. Furthermore, our study provides the model structure for an additional tool (EU-TOPIA CRC evaluation tool: http://miscan.eu-topia.org) that aims to help policymakers and researchers monitoring or improving CRC screening in Europe.
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OBJECTIVE: The national population-based colorectal cancer screening programme in Hungary was initiated in December 2018. We aimed to evaluate the current programme and investigate the costs and benefits of potential future changes to overcome the low coverage of the target population. METHODS: We performed an economic evaluation from a healthcare payer perspective using an established micro-simulation model (Microsimulation Screening Analysis-Colon). We simulated costs and benefits of screening with fecal immunochemical test in the Hungarian population aged 50-100, investigating also the impact of potential future scenarios which were assumed to increase invitation coverage: improvement of the IT platform currently used by GPs or distributing the tests through pharmacies instead of GPs. RESULTS: The model predicted that the current screening programme could lead to 6.2% colorectal cancer mortality reduction between 2018 and 2050 compared to no screening. Even higher reductions, up to 16.6%, were estimated when tests were distributed through pharmacies and higher coverage was assumed. This change in the programme was estimated to require up to 26 million performed fecal immunochemical tests and 1 million colonoscopies for the simulated period. These future scenarios have acceptable cost-benefit ratios of 8000-8700 per life-years gained depending on the assumed adherence of invited individuals. CONCLUSIONS: With its limitations, the current colorectal cancer screening programme in Hungary will have a modest impact on colorectal cancer mortality. Significant improvements in mortality reduction could be made at acceptable costs, if the tests were to be distributed by pharmacies allowing the entire target population to be invited.
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Neoplasias Colorretais , Detecção Precoce de Câncer , Colonoscopia , Neoplasias Colorretais/diagnóstico , Análise Custo-Benefício , Humanos , Hungria , Programas de Rastreamento , Sangue OcultoRESUMO
Pnictogen-bond donors are attractive for use in catalysis because of deep σ holes, high multivalency, rich hypervalency, and chiral binding pockets. We here report natural product inspired epoxide-opening polyether cyclizations catalyzed by fluoroarylated Sb(v) > Sb(iii) > Bi > Sn > Ge. The distinctive characteristic found for pnictogen-bonding catalysis is the breaking of the Baldwin rules, that is selective endo cyclization into the trans-fused ladder oligomers known from the brevetoxins. Moreover, tris(3,4,5-trifluorophenyl)stibines and their hypervalent stiborane catecholates afford different anti-Baldwin stereoselectivity. Lewis (SbCl3), Brønsted (AcOH) and π acids fail to provide similar access to these forbidden rings. Like hydrogen-bonding catalysis differs from Brønsted acid catalysis, pnictogen-bonding catalysis thus emerges as the supramolecular counterpart of covalent Lewis acid catalysis.
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Pnictogen-bonding catalysis and supramolecular σ-hole catalysis in general is currently being introduced as the non-covalent counterpart of covalent Lewis acid catalysis. With access to anti-Baldwin cyclizations identified as unique characteristic, pnictogen-bonding catalysis appeared promising to elucidate one of the hidden enigmas of brevetoxin-type epoxide opening polyether cascade cyclizations, that is the cyclization of certain trans epoxides into cis-fused rings. In principle, a shift from SN 2- to SN 1-type mechanisms could suffice to rationalize this inversion of configuration. However, the same inversion could be explained by a completely different mechanism: Ring opening with C-C bond cleavage into a branched hydroxy-5-enal and the corresponding cyclic hemiacetal, followed by cascade cyclization under conformational control, including stereoselective C-C bond formation. In this report, a pnictogen-bonding supramolecular SbV catalyst is used to demonstrate that this unorthodox polyether cascade cyclization mechanism occurs.