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The relationship between Helicobacter pylori (H. pylori) infection and upper gastrointestinal (UGI) cancers is complex. This multicenter, population-based cohort study conducted in seven areas in China aimed to assess the correlation between current H. pylori infection and the severity of UGI lesions, as well as its association with the risk of gastric cancer (GC) and esophageal cancer (EC). From 2015 to 2017, 27,085 participants (aged 40-69) completed a standardized questionnaire, and underwent a 13C-urea breath test. Then a subset underwent UGI endoscopy to assess the UGI lesion detection rates. All individuals were followed up until December 2021 to calculate the hazard ratios (HRs) for UGI cancers. H. pylori infection prevalence was 45.9%, and among endoscopy participants, 22.2% had gastric lesions, 19.2% had esophageal lesions. Higher detection rates of gastric lesions were noted in the H. pylori-positive population across all lesion severity levels. Over a median follow-up of 6.3 years, 104 EC and 179 GC cases were observed, including 103 non-cardia gastric cancer (NCGC) cases and 76 cardia gastric cancer (CGC) cases. H. pylori-infected individuals exhibited a 1.78-fold increased risk of GC (HR 1.78, 95% confidence interval [CI] 1.32-2.40) but no significant increase in EC risk (HR 1.07, 95% CI 0.73-1.57). Notably, there was a higher risk for both NCGC and CGC in H. pylori-infected individuals. This population-based cohort study provides valuable evidence supporting the association between current H. pylori infection and the risk of both NCGC and CGC. These findings contribute to the empirical basis for risk stratification and recommendations for UGI cancer screening.
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Neoplasias Esofágicas , Infecções por Helicobacter , Helicobacter pylori , Neoplasias Gástricas , Humanos , Infecções por Helicobacter/complicações , Infecções por Helicobacter/epidemiologia , Pessoa de Meia-Idade , Masculino , Feminino , Helicobacter pylori/isolamento & purificação , Adulto , Neoplasias Gástricas/microbiologia , Neoplasias Gástricas/epidemiologia , Neoplasias Gástricas/etiologia , Neoplasias Gástricas/patologia , Idoso , Neoplasias Esofágicas/epidemiologia , Neoplasias Esofágicas/microbiologia , Neoplasias Esofágicas/etiologia , China/epidemiologia , Estudos de Coortes , Fatores de Risco , Prevalência , Neoplasias Gastrointestinais/microbiologia , Neoplasias Gastrointestinais/epidemiologia , Neoplasias Gastrointestinais/etiologia , Trato Gastrointestinal Superior/patologia , Trato Gastrointestinal Superior/microbiologiaRESUMO
Geographic and sex differences in esophageal cancer have been reported in China, but data are lacking at the local level. We aimed to investigate geographic and sex disparities in esophageal cancer incidence among Chinese counties and whether county-level socioeconomic status was associated with these variations. We obtained esophageal cancer data from 2015 to 2017 for 782 counties from population-based cancer registries in China. We calculated age-standardized incidence rates and male-to-female incidence rate ratios (IRRs) by county. We performed hotspot analysis to identify geographical clusters. We used negative binomial regression models to analyze the association between incidence rates and county-level socioeconomic factors. There were significant geographic disparities in esophageal cancer incidence, with 8.1 times higher rate in the 90th-percentile county than in the 10th-percentile county (23.7 vs 2.9 per 100 000 person-years). Clusters of elevated rates were prominent across north-central China. Nationally, men had 2.9 times higher incidence of esophageal cancer than women. By county, the male-to-female IRRs ranged from 1.1 to 21.1. Clusters of high male-to-female IRRs were observed in northeast China. Rurality (IRR 1.16, 95% CI 1.10-1.22), per capita gross domestic product (IRR 0.95, 0.92-0.98) and percentage of people with a high school diploma (IRR 0.86, 0.84-0.87) in a county were significantly associated with esophageal cancer incidence. The male-to-female IRRs were higher in counties with higher socioeconomic status. Substantial differences in incidence rates and sex ratios of esophageal cancer exist between Chinese counties, and county-level socioeconomic status was associated with these variations. These findings may inform interventions to reduce these disparities.
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Neoplasias Esofágicas , Disparidades Socioeconômicas em Saúde , Humanos , Masculino , Feminino , Incidência , Neoplasias Esofágicas/epidemiologia , Fatores Socioeconômicos , China/epidemiologiaRESUMO
RNA N6-methyladenosine (m6A) readers mediate cancer progression. However, the functional role and potential mechanisms of the m6A readers in prostate cancer tumorigenicity remain to be elucidated. In this study, we demonstrate that YTHDF3 expression is elevated in castration-resistant prostate cancer (CRPC) and positively correlated to high grade, bone metastasis and poor survival. YTHDF3 expression promoted CRPC cell proliferation, epithelial to mesenchymal transition (EMT) and tumour progression. Mechanistically, YTHDF3 promoted the RNA degradation of SPOP and NXK3.1 but stabilized RNA expressions of TWIST1 and SNAI2 dependent on m6A to facilitate cell proliferation and EMT. Additionally, YTHDF3 expression enhanced AKT activity via degrading SPOP in an m6A-dependent manner. Importantly, we found that melatonin can compete with m6A to occupy the m6A-binding cage of YTHDF3, leading to inhibition of YTHFD3 and its target expressions as well as CRPC tumour growth. Our findings uncover an essential role of YTHDF3 in the progression of CRPC and highlight the role of melatonin in anti-CRPC activity.
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Progressão da Doença , Neoplasias de Próstata Resistentes à Castração , Proteínas de Ligação a RNA , Masculino , Neoplasias de Próstata Resistentes à Castração/metabolismo , Neoplasias de Próstata Resistentes à Castração/genética , Neoplasias de Próstata Resistentes à Castração/patologia , Humanos , Proteínas de Ligação a RNA/metabolismo , Proteínas de Ligação a RNA/genética , Animais , Linhagem Celular Tumoral , Adenosina/análogos & derivados , Adenosina/metabolismo , Proliferação de Células/genética , Camundongos , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica , Melatonina/metabolismo , Camundongos NusRESUMO
The arrangement of functional groups exerts a crucial role in determining the characteristics of compounds. In this study, we synthesized two novel short-wave ultraviolet (UV) nonlinear optical (NLO) crystals: KBe2(SeO3)2(OH)·H2O and K2Be(SeO3)2. Interestingly, the two compounds show the same SeO3 triangular pyramids and K-O polyhedra. However, the two compounds exhibit distinct beryllium-oxygen anion groups: BeO3(OH) for KBe2(SeO3)2(OH)·H2O and BeO4 for K2Be(SeO3)2. This results in the SeO3 groups within the structure having different orientations, ultimately leading to the two compounds exhibiting completely different optical properties. KBe2(SeO3)2(OH)·H2O displays a large second harmonic generation (SHG) effect equivalent to 2× KH2PO4 (KDP), coupled with a large birefringence of 0.078 at 546 nm. In contrast, the SHG effect and birefringence of K2Be(SeO3)2 are only 0.33× that of KDP and 0.024 at 546 nm, respectively. Structural analyses and theoretical calculations indicate that these pronounced differences in optical properties stem from variations in the arrangement of the SeO3 functional groups. This study not only sheds light on the correlation between crystal structure and optical behavior but also presents a hopeful avenue for the advancement of materials in the short-wave UV spectrum.
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A novel zinc phosphate derivative of Sr2Be2B2O7 (SBBO), K(NH4)Zn2(PO4)2 (KNZP), featuring [Zn2P2O8]∞2- double layers akin to the [Be2B2O7]∞4- layers in SBBO, was successfully synthesized via a moderate hydrothermal method. Through the substitution of BeO4 and BO3 with ZnO4 and PO4, the issue of toxicity has been effectively resolved, while the enhanced interlayer interactions facilitated by covalent and hydrogen bonding in KNZP overcome the inherent structural instability. Notably, KNZP exhibits a wide transparent window and a moderate second-harmonic generation (SHG) intensity, reaching 0.7 times that of KH2PO4 (KDP), rendering it type-I phase-matchable, indicating that it is a promising UV nonlinear optical (NLO) material.
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A new open-framework tin(II) sulfate, formulated as C4H12N2·Sn(SO4)2·H2O, was prepared under the structure-directing effect of piperazine. This compound features a 3D structure with 16-ring channels. Under ultraviolet light irradiation, it emits bright yellow luminescence with a near-unity photoluminescence quantum yield. Theoretical calculations were carried out to understand the luminescence mechanism.
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Three new homochiral metal bromides, namely, (l-Htp)2Cu2Br4 (1), (l-Htp)(l-tp)CdBr3 (2), and (l-tp)2ZnBr2 (3), were prepared using l-thioproline as the chiral template. These compounds feature dimeric, chainlike, and monomeric structures. Their second-harmonic-generation (SHG) efficiencies are 0.1, 0.3, and 2.0 times that of KH2PO4, respectively. Density functional theory calculations were performed to reveal the origin of the SHG response of compound 3.
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Three organic-inorganic metal iodides, namely, (NH4)(l-hp)ZnI3 (1), [Cd(l-hp)4]Cd3I8 (2), and (l-Hhp)(l-hp)PbI3 (3), have been synthesized using l-homoproline (l-hp) as the structure-directing agent. These compounds feature different noncentrosymmetric structures and optical properties. In particular, compound 3 shows a large second-harmonic-generation response of 3.4 times that of KH2PO4. Density functional theory calculations were performed to gain insight into its structure-property relationship.
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Natural minerals, with their adaptable framework structures exemplified by perovskite and lyonsite, have sparked substantial interest as potential templates for the design of advanced functional solid-state materials. Nonetheless, the quest for new materials with desired properties remains a substantial challenge, primarily due to the scarcity of effective and practical synthetic approaches. In this study, we have harnessed a synergistic approach that seamlessly integrates first-principles high-throughput screening and crystal engineering to reinvigorate the often-overlooked fresnoite mineral, Ba2 TiOSi2 O7 . This innovative strategy has culminated in the successful synthesis of two superior inorganic UV nonlinear optical materials, namely Rb2 TeOP2 O7 and Rb2 SbFP2 O7 . Notably, Rb2 SbFP2 O7 demonstrates a comprehensive enhancement in nonlinear optical performance, featuring a shortened UV absorption edge (260â nm) and a more robust second-harmonic generation response (5.1×KDP). Particularly striking is its significantly increased birefringence (0.15@546â nm), which is approximately 30 times higher than the prototype Ba2 TiOSi2 O7 (0.005@546â nm). Our research has not only revitalized the potential of the fresnoite mineral for the development of new high-performance UV nonlinear optical materials but has also provided a clearly defined roadmap for the efficient exploration of novel structure-driven functional materials with targeted properties.
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This study pioneers a novel strategy for synthesizing solar-blind ultraviolet (UV) nonlinear optical (NLO) crystals through functional groups sequential construction, effectively addressing the inherent trade-offs among broad transmittance, enhanced second-harmonic generation (SHG), and optimal birefringence. We have developed two innovative van der Waals layered germanous phosphites: GeHPO3, the first Ge(II)-based oxide NLO crystal which exhibits a black phosphorus-like structure, and K(GeHPO3)2Br, distinguished by its exceptional birefringence and graphene-like structure. Significantly, GeHPO3 exhibits a remarkable array of NLO properties, including the highest SHG coefficient recorded among all NLO crystals for phase-matching and generating 266â nm coherent light via quadruple frequency conversion. It delivers a potent SHG intensity, surpassing KH2PO4 (KDP) by 10.3â times at 1064â nm and ß-BaB2O4 by 1.3â times at 532â nm, complemented by a distinct UV absorption edge at 211â nm and moderate birefringence of 0.062 at 546â nm. Comprehensive theoretical analysis links these exceptional characteristics to the unique NLO-active GeO3 4- units and the distinctive, highly ordered layered structures. Our findings deliver essential experimental insights into the development of Ge(II)-based optoelectronic materials and present a strategic blueprint for engineering structure-driven functional materials with customized properties.
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Homochiral halide perovskites have gained increasing attention because of their fascinating optoelectronic properties and prospective applications in laser technologies. However, the limited choice of chiral organic templates severely restricts their structural diversity and second-harmonic generation (SHG) effects. Here, we present an in situ chiral template approach for the synthesis of one-dimensional (1D) homochiral lead iodides. A chiral imine (L-ipp) template was generated in situ by reacting L-proline (L-pro) and acetone under ambient conditions. Notably, L-ipp can cooperate with L-pro to direct the formation of a homochiral lead iodide with dual chiral templates, which is unprecedented in crystalline metal halides. The homochiral lead iodide containing both L-ipp and L-pro shows a strong SHG response of 8.0â times that of KH2 PO4 (8.0×KDP). The SHG efficiency is one of the largest values reported to date for any homochiral lead halides under 1064â nm laser irradiation. A comparative study shows that homochiral 1D lead iodides containing either L-ipp or L-pro exhibit relatively weak SHG responses (≤1.0×KDP). This work demonstrates the advantage of using two different chiral templates over a single chiral template in enhancing the SHG responses of halide materials.
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Achieving tunable emissions spanning the spectrum, from blue to near-infrared (NIR) light, within a single component is a formidable challenge with significant implication, particularly in tailoring multicolor luminescence for anti-counterfeiting purposes. In this study, we demonstrate a broad spectrum of emissions, covering blue to red and extending into NIR light in [BPy]2CdX4 : xSb3+ (BPy=Butylpyridinium; X=Cl, Br; x=0 to 0.08) through precise multisite structural fine-tuning. Notably, the multicolor emissions from [BPy]2CdBr4 : Sb3+ manifest a distinctive pattern, transitioning from blue to yellow in tandem with the host [BPy]2CdBr4 and further extending from yellow to NIR with its homologous [BPy]2CdCl4 : Sb3+, resulting in the simultaneous presence of intersecting and independent emission colors. Detailed modulation of chemical composition enables partial luminescence switching, facilitating the creation of diverse patterns with multicolor luminescence by employing [BPy]2CdX4 : xSb3+ as phosphors. This study for the first time successfully implements several groups of tunable emission colors in a single matrix via multisite fine-tuning. Such an effective strategy not only develops the specific relationships between tunable emissions and adjustable compositions, but also introduces a cost-effective and straightforward approach to achieving unique, high-level, plentiful-color and multiple-information-storage labels for advanced anti-counterfeiting applications.
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Adenocarcinoma (AC) and squamous cell carcinoma (SCC) are the main subtypes of esophageal cancer (EC), but nationwide survival of both EC subtypes has never been reported in China. Our study aimed to estimate the survival trends of EC by subtype in China and compare them with those in the United States for the same period. We used data from 64 Chinese cancer registries, which included EC patients diagnosed during 2008 and 2015 and followed up until 31st December 2017. The 5-year age-standardized relative survival by subtype, sex, age group and urban or rural area between 2008 and 2017 were analyzed. We stratified survival estimates by calendar period (2008-2009, 2010-2011, 2012-2014 and 2015-2017). Data from the SEER 18 program were calculated to estimate the survival of EC in the United States. A further comparison between the survivals in areas covered and not covered by population-based endoscopic screening programs in China was conducted. A total of 129 962 records were included in the survival analyses. Results revealed that age-standardized 5-year relative survivals for AC and SCC increased in both China and the United States from 2008 to 2017. In 2015 to 2017, 5-year survival from both subtypes in China was better than the United States (SCC: 36.9% vs 18.5%, AC: 34.8% vs 22.3%). The survival for both subtypes was significantly higher in screening areas than in nonscreening areas in China (SCC: 40.6% vs 32.8%; AC: 43.0% vs 31.3%). A survival gap in EC by subtype exists between China and the United States. Our results may support the beneficial effect of population-based endoscopic screening for survival, and may be poised to inform national policy-making in both countries.
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Adenocarcinoma , Carcinoma de Células Escamosas , Neoplasias Esofágicas , Humanos , Estados Unidos/epidemiologia , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas/patologia , Programa de SEER , Adenocarcinoma/patologia , China/epidemiologiaRESUMO
BACKGROUND & AIMS: Mild and moderate dysplasia are major premalignant lesions of esophageal squamous cell carcinoma (ESCC); however, evidence of the progression risk in patients with these conditions is extremely limited. We aimed to assess the incidence and risk factors for advanced neoplasia in patients with mild-moderate dysplasia. METHODS: This prospective cohort study included patients with mild-moderate dysplasia from 9 regions in rural China. These patients were identified from a community-based ESCC screening program conducted between 2010 and 2016 and were offered endoscopic surveillance until December 2021. We estimated the incidence of advanced esophageal neoplasia, including severe dysplasia, carcinoma in situ, or ESCC, and identified potential risk factors using the Cox regression model. RESULTS: The 1183 patients with mild-moderate dysplasia were followed up over a period of 6.95 years. During follow-up evaluation, 88 patients progressed to advanced neoplasia (7.44%), with an incidence rate of 10.44 per 1000 person-years. The median interval from the progression of mild-moderate dysplasia to advanced neoplasia was 2.39 years (interquartile range, 1.58-4.32 y). A total of 74.47% of patients with mild-moderate dysplasia experienced regression to nondysplasia, and 18.09% showed no lesion progression. Patients with mild-moderate dysplasia who had a family history of esophageal cancer and were age 55 years and older showed 97% higher advanced neoplasia yields than all patients with mild-moderate dysplasia. CONCLUSIONS: In a country with a high incidence of ESCC, patients with mild-moderate dysplasia showed an overall risk of advanced neoplasia progression of 1.04% per year. Patients with mild-moderate dysplasia would be recommended for endoscopic surveillance during the first 2 to 3 years.
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Carcinoma de Células Escamosas , Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Lesões Pré-Cancerosas , Humanos , Pessoa de Meia-Idade , Neoplasias Esofágicas/diagnóstico , Carcinoma de Células Escamosas/patologia , Estudos Prospectivos , Lesões Pré-Cancerosas/patologia , Esofagoscopia , HiperplasiaRESUMO
With increasing incidence and mortality, cancer is the leading cause of death in China and is a major public health problem. Because of China's massive population (1.37 billion), previous national incidence and mortality estimates have been limited to small samples of the population using data from the 1990s or based on a specific year. With high-quality data from an additional number of population-based registries now available through the National Central Cancer Registry of China, the authors analyzed data from 72 local, population-based cancer registries (2009-2011), representing 6.5% of the population, to estimate the number of new cases and cancer deaths for 2015. Data from 22 registries were used for trend analyses (2000-2011). The results indicated that an estimated 4292,000 new cancer cases and 2814,000 cancer deaths would occur in China in 2015, with lung cancer being the most common incident cancer and the leading cause of cancer death. Stomach, esophageal, and liver cancers were also commonly diagnosed and were identified as leading causes of cancer death. Residents of rural areas had significantly higher age-standardized (Segi population) incidence and mortality rates for all cancers combined than urban residents (213.6 per 100,000 vs 191.5 per 100,000 for incidence; 149.0 per 100,000 vs 109.5 per 100,000 for mortality, respectively). For all cancers combined, the incidence rates were stable during 2000 through 2011 for males (+0.2% per year; P = .1), whereas they increased significantly (+2.2% per year; P < .05) among females. In contrast, the mortality rates since 2006 have decreased significantly for both males (-1.4% per year; P < .05) and females (-1.1% per year; P < .05). Many of the estimated cancer cases and deaths can be prevented through reducing the prevalence of risk factors, while increasing the effectiveness of clinical care delivery, particularly for those living in rural areas and in disadvantaged populations.
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Neoplasias/epidemiologia , População Rural/estatística & dados numéricos , População Urbana/estatística & dados numéricos , Adulto , Idoso , China/epidemiologia , Neoplasias Esofágicas/epidemiologia , Feminino , Humanos , Incidência , Neoplasias Hepáticas/epidemiologia , Neoplasias Pulmonares/epidemiologia , Masculino , Pessoa de Meia-Idade , Neoplasias/diagnóstico , Neoplasias/mortalidade , Prevalência , Fatores de Risco , Distribuição por Sexo , Neoplasias Gástricas/epidemiologia , Taxa de SobrevidaRESUMO
The combination of π-conjugated oxalate anion with sulfate group has been explored in the solvent-free synthesis of two new magnesium sulfate oxalates. One of them has a layered structure crystallized in the noncentrosymmetric space group Ia, while the other has a chainlike structure crystallized in the centrosymmetric space group P21/c. The noncentrosymmetric solid has a wide optical bandgap and exhibits a moderate second-harmonic-generation response. Density functional theory calculations were carried out to disclose the origin of its second-order nonlinear-optical response.
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Three homochiral organic-inorganic hybrid antimony halides, namely, (L-Hhis)2Sb2Cl8 (1), L-H2his·SbBr5·H2O (2), and (L-H2his)2·Sb3I13·4H2O (3), were prepared to investigate the structure-directing roles of l-histidine (l-his). These compounds feature dimeric, chainlike, and trimeric structures with different optical bandgaps. They display second-harmonic-generation (SHG) responses of 0.1, 2.6, and 0.05 times that of KH2PO4, respectively. Theoretical calculations for compound 2 were carried out to get insights into its structure-property relationship.
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Herein, two new Sb3+-based phosphites, Sb2O2(HPO3) (I) and Sb2O(HPO3)2 (II), were successfully obtained by ingeniously combining Sb3+-based polyhedra containing stereochemically active lone pair (SCALP) and HPO3 polar groups. Both reported compounds exhibit unique 2D van der Waals layered structures, [Sb4O4(HPO3)2]∞ and [Sb2O(HPO3)2]∞, respectively, which favors compounds with large optical anisotropy. Interestingly, the different curvatures of the two layers resulted in the two title compounds showing significantly different birefringences (0.079@546 and 0.046@546 nm, respectively). Both compounds endow wide optical band gaps (4.32 and 4.54 eV, respectively), which indicates their potential as promising ultraviolet (UV) birefringent crystals. The synthesis of the two title compounds enriched Sb3+-based phosphites in the UV region and provided guidance for the subsequent synthesis of superior optical materials.
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BACKGROUND: population ageing contributes to increased cancer cases and deaths and has profound implications for global healthcare systems. We estimated the trends of cancer cases and deaths in ageing populations at global and regional levels. METHODS: using data from the Global Burden of Disease Study 2019, we analysed the change in cancer cases and deaths associated with population ageing, population growth and epidemiological factors from 1990 to 2019 using decomposition analysis. Additionally, we estimated the proportions of people aged 65 years and over accounting for total cases and deaths, and investigated relationships between the proportions and the Sociodemographic Index (SDI) using the Pearson correlation coefficient. RESULTS: from 1990 to 2019, there was an increase of 128.9% for total cases and 74.8% for total deaths in all cancers combined; the percentages of older people increased from 48.6% to 56.4% for cases and from 52.0% to 61.9% for deaths. Population ageing contributed to the largest increase in global cancer occurrence, with 56.5% for cases and 63.3% for deaths. However, the changes attributed to epidemiological factors was 5.2% for cancer cases and -33.4% for cancer deaths. The proportions of total cases and deaths of older adults were positively correlated with socioeconomic development of the country. CONCLUSION: our findings revealed that the main contributor to increased cancer cases and deaths has changed from comprehensive epidemiological factors to demographic shifts. To respond to the rapidly growing occurrence of cancer in ageing populations, the global health priority should focus on meeting the rising demand for cancer diagnosis, treatment and care services for older people.
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Neoplasias , Humanos , Idoso , Neoplasias/diagnóstico , Neoplasias/epidemiologia , Neoplasias/terapia , Envelhecimento , Prioridades em SaúdeRESUMO
A male predominance was observed in esophageal and gastric cancers, though present limited data has revealed variations by age. We aim to investigate the global age-specific sex differences in esophageal squamous cell carcinoma (ESCC), esophageal adenocarcinoma (EAC), gastric cardia cancer (GCC) and gastric noncardia cancer (GNCC). Data on esophageal and gastric cancers incidence by diagnosis year, sex, histology, subsite and age group were extracted from 171 registries in 54 countries included in the last two volumes (X and XI, 2003-2012) of Cancer Incidence in Five Continents, which contributing to over 80% of the global burdens of these cancers. Age-standardized incidence rates (ASIRs) and male-to-female ASIRs ratios were estimated for esophageal and gastric cancers, by histological subtype and subsite, globally and by country. We consistently observed a male predominance in esophageal and gastric cancers across the world from 2003 to 2012, with male-to-female ASIRs ratios of 6.7:1 for EAC, 3.3:1 for ESCC, 4.0:1 for GCC and 2.1:1 for GNCC. The sex differences were consistent across time periods but varied significantly by age across the life span. Across the four cancer types, the male-to-female incidence rate ratios increased from young ages, approaching a peak at ages 60-64, but sharply declined thereafter. Similar "low-high-low" trends of age-specific sex ratio were observed in other digestive cancers including liver, pancreas, colon and rectum with peak ages ranging from 50 to 65. Age-dependent risk factors warrant further investigation to aid our understanding of the underlying etiologies of esophageal and gastric cancers by histological subtype and subsite.