Trends In Gastric Cancer Incidence Research Articles

Trends in gastric cancer incidence and mortality in Asia and association analysis with human development index, 1990-2019

ObjectivesTo describe the epidemiological time trends and gender, age and regional differences of gastric cancer in Asia during 1990–2019, and to analyze the association between the human development index (HDI) and the statistical indicators of the burden of disease. MethodsDescribing trends in age-standardized incidence rates (ASIR) and age-standardized mortality rate (ASMR) in Asia from 1990 to 2019 based on GBD-reported population-based surveillance of gastric cancer in Asia. Obtained ASIR, ASMR, and mortality to incidence ratios (MIR) for gastric cancer in different countries in 2019, with association analysis by Kruskal-Wallis nonparametric test. ResultsThe annual percentage change in ASIR and ASMR in Asia from 1990 to 2019 was − 1.20% and − 1.91%. Male gastric cancer patients have higher ASIR and ASMR than female gastric cancer patients. Decreasing trends in ASIR and ASMR for the total population in five Asian regions. From 1990 to 2019, the average annual change in ASMR was − 2.45%, − 1.43%, − 0.53%, − 0.62%, and − 0.27% for Central Asia, East Asia, high-income Asia-Pacific, South Asia, and Southeast Asia, respectively (p < 0.05). Both incidence and mortality were concentrated in the age groups of 85–89 and 89–94 years. Classifying Asian countries into different levels of HDI, only MIR was associated with HDI levels. ConclusionASIR and ASMR of gastric cancer in the total population, different regions, and countries in Asia from 1990 to 2019 showed an overall decreasing trend. The MIR index is suggestive of survival rates and the role of cancer care in individual countries. Asian countries should develop different strategies for gastric cancer screening and prevention according to high-risk age, high-risk gender and HDI.

Esophageal and gastric cancer incidence trends in Golestan, Iran: An age-period-cohort analysis 2004 to 2018.

Golestan province in the northeast of Iran is part of the Asian esophageal cancer belt and is known as a high-risk area for esophageal (EC) and gastric cancers (GC). Data on incident cases of EC and GC during 2004 to 2018 were obtained from the Golestan Population-based Cancer Registry (GPCR). The age-standardized incidence rates (ASRs) were calculated and presented per 100 000 person-years. The estimated annual percentage change (EAPC) with 95% confidence interval (95% CI) were calculated. We also fitted age-period-cohort (APC) models to assess nonlinear period and cohort effects as incidence rate ratios (IRRs). Overall, 3004 new cases of EC (ASR = 15.7) and 3553 cases of GC (ASR = 18.3) were registered in the GPCR. We found significant decreasing trends in incidence rates of EC (EAPC = -5.0; 95% CI: -7.8 to -2.2) and less marked nonsignificant trends for GC (EAPC = -1.4; 95% CI: -4.0 to 1.4) during 2004 to 2018. There was a strong cohort effect for EC with a consistent decrease in the IRR across successive birth cohorts, starting with the oldest birth cohort (1924; IRR = 1.9 vs the reference birth cohort of 1947) through to the most recent cohort born in 1988 (IRR = 0.1). The marked declines in EC incidence rates in Golestan relate to generational changes in its underlying risk factors. Despite favorable trends, this population remains at high risk of both EC and GC. Further studies are warranted to measure the impact of the major risk factors on incidence with a view to designing effective preventative programs.

Gastric cancer incidence trends in China and Japan from 1990 to 2019: Disentangling age-period-cohort patterns.

Recent data have shown divergent trends in gastric cancer (GC) incidence between China and Japan; however, the cause for has not been explored. We retrieved GC incidence data from 1990 to 2019 from the Global Burden of Disease study, stratified by sex for both countries. We analyzed annual average percentage change (AAPC) via a joinpoint regression model and estimated the effects of age, period, and cohort via the age-period-cohort model. The age-standardized incidence rate trends for GC decreased in both countries and both sexes, but the reduction was more pronounced in Japan because the AAPC for Japanese males (AAPC=-2.65%; 95% CI, -2.98 to -2.32) was eight times greater than that of Chinese males (AAPC=-0.30%; 95% CI, -0.5 to -0.09). The age and cohort effects on the trend are similar in both countries: the risk of GC incidence increased with age among the Chinese and the Japanese but was lower among younger birth cohorts. The two countries showed contrasting trends over the study period; although the risk of GC rapidly decreased for Japanese males and females, it increased by twofold among Chinese males. The period effect is the main reason for the divergent trends in age-standardized incidence rate for GC in China and Japan. By comparing national cancer control programs in both countries, we concluded that countries with a high prevalence of GC, such as China, can learn from Japan's experience in controlling GC by actively conducting national population screening, which is expected to facilitate both prevention and treatment of GC. More than one-half of all new gastric cancer (GC) worldwide occur in China and Japan, but the reasons for the different incidence trends have not been thoroughly analyzed. Analysis using the age-period-cohort model confirmed that the cohort effect was the main reason for the decline in age-standardized incidence rate (ASIR) for GC and that the period effect may be the main reason for the divergent trends in gastric cancer ASIR in China and Japan.

Changing trends in gastric cancer incidence and mortality: the role of upper endoscopy in low-risk countries.

Gastric cancer, which is diagnosed in approximately one million new patients annually, is a significant contributor to global cancer burden and cancer-related mortality [1]. East Asia, eastern Europe, and Latin America have the highest incidences, while North America and most of western Europe have relatively low incidences [2]. This geographical variation is thought to be associated with several different predisposing and etiologic factors among the countries, such as tumor biology, Helicobacter pylori (H. pylori) infection rate, cigarette smoking, and a high sodium diet with salt-preserved foods. Global age-standardized gastric cancer incidence has steadily declined over the past century, particularly in high-risk countries such as Korea and Japan. This trend has been linked to a decline in noncardia cancer because of the eradication of H. pylori [2]. Contrarily, in countries with low gastric cancer incidence, such as those in western Europe and the USA, the decline in gastric cancer has reduced, especially in the middle-aged population [1] [2]. This phenomenon may also be related to changes in H. pylori infection patterns or the increased proportion of cardia cancer related to epidemic obesity and gastroesophageal reflux disease [1]. As with incidence, global gastric cancer mortality has also decreased [2]. Improvements in surgical techniques and the development of chemotherapy regimens have led to better survival outcomes. Above all, early detection of cancer is a crucial factor contributing to the decline in mortality.

Incidence Trends of Gastric Cancer in Southern Iran: Adenocarcinoma and Non-cardia Gastric Cancer Are More Rising Among Younger Ages.

Gastric Cancer (GC) is still one of the major causes of cancer mortality. Due to health-related transitions, the epidemiology of GC subtypes may change. These changes may have profound effects on clinical approaches as well as on public health management of GC. Iran, as a developing country, has experienced huge demographic and epidemiological transitions duringthe recent decades. This study aimed to investigate thesubtype-specific population-based incidence trends of GC in southern Iran. We used data on GC incidence in southern Iran during 2001-2015. Data preparation and subtype grouping were done based on the ICD-O-3. Thetrends of Age-Standardized incidence Rate (ASR), truncated ASRs, incidence rate of adenocarcinoma, and cardia GC, and age-gender specific rates were analyzed using joinpoint regression modeling. Annual Percentage Change (APC) and its 95% Confidence Intervals (CIs) were estimated. Overall APC was estimated as 7.2 for males and 8.7 for females. Theestimated APCs for thetrends of overall GC, and gastric adenocarcinoma were stable in both genders during 2009-2015. Nonetheless, cardia GC showed increasingtrends in both genders. The estimated APCs for thetrends of non-cardia GC was also stable. The overall trends of the GCincidence in southern Iran were stable during the past decade. However, significant and different changeshave occured in the pattern of GC. Thus,etiological and prognostic studies are needed for theimprovement of GC managementin Iran.

Secular decreasing trends in gastric cancer incidence in Taiwan: A population-based cancer registry study.

BACKGROUNDGastric cancer remains a leading cause of cancer death worldwide. In Taiwan, gastric cancer is the sixth leading cause of cancer mortality in both males and females.AIMTo evaluate secular trends in gastric cancer incidence according to age, sex, and Helicobacter pylori (H. pylori) treatment in Taiwan.METHODSIn this population-based study, we used the national Taiwan Cancer Registry database. Annual percent changes in incidence rates were used to describe secular trends in incidence rates and sex ratios of gastric cancer in Taiwan. Pearson’s product-moment correlation coefficients were used to analyze the correlation between annual age-adjusted incidence rates and the annual number of patients treated with antibiotic therapy for H. pylori infection.RESULTSThe annual percent changes showed continuously decreasing rates of gastric cancer among both males and females. However, the decreasing trends differed by sex, with an annual percent change of -2.58% in males and -2.14% in females. The age-specific incidence rates increased with age. Within the same age group, more recent time periods showed lower incidence rates than greater time periods. Similarly, the sex ratio was lower in later birth cohorts than in earlier birth cohorts. Age-adjusted incidence rates substantially decreased with increasing numbers of patients being treated with antibiotic therapy for H. pylori infection during 2005 to 2016 (r = 0.72).CONCLUSIONWe observed steadily decreasing trends with differential sex ratios in the incidence of gastric cancer in Taiwan. These results support H. pylori eradication programs in Taiwan.

Analysis of the Incidence and Survival of Gastric Cancer Based on the Lauren Classification: A Large Population-Based Study Using SEER.

Background: Limited evidence exists on the incidence of gastric cancer (GC), and contradictory results exist for the prognosis of GC based on the Lauren classification. We analyzed the incidence and survival of GC based on the Lauren classification.Methods: The Surveillance, Epidemiology, and End Results (SEER) database from 1975 through 2015 was used to identify all patients with surgically resected, histologically diagnosed intestinal or diffused-type GC. Propensity score matching was used to analyze the association between the Lauren classification type and prognosis.Results: The trend of total GC incidence showed an obvious decrease (APC = −1.51, 95% CI: −2.31 to −1.01) as well as that of the intestinal type (APC = −1.43, 95% CI: −2.01 to −1.12). However, we found that the relative incidence of the diffused type was increased (APC = 0.6, 95% CI: 0.41–0.82). The trend of the total incidence of GC (APC = −1.31, 95% CI: −1.91 to −1.03) and that of the intestinal type (APC = −1.11, 95% CI: −1.53 to −0.98) was decreased in 40–49-year-olds, but that of the diffused type was increased (APC = 1.5, 95% CI: 1.2–1.72). We found that trends in GC incidence exhibited a similar pattern in the regional and distant stages and showed a decrease from 1975 through 2015. However, the incidence rate of the local stage was increased, with an APC of 0.5 (95% CI: 0.3–0.7). We identified 15,989 GC cases from the SEER database, including 13,852 intestinal-type and 2,138 diffused-type cases. The 1,336 intestinal-type cases were matched with 1,336 diffused-type cases using propensity score matching (PSM), and patients with the diffused type had a better prognosis than patients with the intestinal type (HR = 0.56, 95% CI: 0.45–0.78). However, we found that patients with diffused-type GC had worse survival than patients with intestinal-type GC in the cohort from Renji Hospital (P < 0.001).Conclusion: The total incidence of GC and that of the intestinal-type GC decreased, but the incidence of diffused-type GC increased in 40–49-year-olds. Diffused types of GCs may have a different prognosis compared to intestinal-type GCs in different patient cohorts. Nevertheless, these results should be interpreted with caution in assessing the prognosis in combination with other factors.

Rapidly declining trend of signet ring cell cancer of the stomach may parallel the infection rate of Helicobacter pylori

BackgroundStudies indicate that gastric cancer (GC) incidence has decreased, whereas signet ring cell carcinoma (SRC) incidence has increased. However, recent trends in GC incidence are unclear. We used our hospital cancer registry to evaluate the changes in the incidence of GC, SRC, and non-SRC (NSRC) over time in comparison to changes in the H. pylori infection rates over time.MethodsWe identified 2532 patients with GC enrolled in our registry between January 2007 and December 2018 and statistically analyzed SRC and NSRC incidence. The H. pylori infection rate in patients with SRC was determined by serum anti-H. pylori antibody testing, urea breath test, biopsy specimen culture, and immunohistochemical analysis (IHC) of gastric tissue. Additionally, genomic detection of H. pylori was performed in SRCs by extracting DNA from formalin-fixed paraffin-embedded gastric tissue and targeting 16S ribosomal RNA of H. pylori.ResultsOverall, 211 patients had SRC (8.3%). Compared with patients with NSRC, those with SRC were younger (P < 0.001) and more likely to be female (P < 0.001). Time series analysis using an autoregressive integrated moving average model revealed a significant decrease in SRC (P < 0.001) incidence; NSRC incidence showed no decline. There was no difference in H. pylori infection prevalence between the SRC and NSRC groups. IHC and genomic methods detected H. pylori in 30 of 37 (81.1%) SRCs.ConclusionsReduction in H. pylori infection prevalence may be associated with the decrease in the incidence of SRC, which was higher than that of NSRC.

The Epidemiology of Gastric Cancers in the Era of Helicobacter pylori Eradication: A Nationwide Cancer Registry-Based Study in Taiwan.

Helicobacter pylori eradication has been shown to decrease gastric adenocarcinoma risk. The epidemiology of gastric lymphoma, which is also associated with H. pylori, and other rare subtypes of gastric cancer is less clear. This study comprehensively evaluated the incidence trend and the survival of gastric cancer in Taiwan by histologic subtype. The incidence trends of gastric cancer in Taiwan from 1996 and 2013 were evaluated using data from the Taiwan Cancer Registry. The life-table method and the Cox proportional hazards analysis were used to evaluate the survival of gastric cancer. The incidence of all gastric cancers in Taiwan decreased from 15.97 per 100,000 in 1996 to 11.57 per 100,000 in 2013. The most frequent histologic subtype of gastric cancer in Taiwan was adenocarcinoma, followed by lymphoma and sarcoma (mainly gastrointestinal stromal tumor). The best survival was in patients with sarcoma, followed by lymphoma, neuroendocrine tumor, and adenocarcinoma. Generally, women had a better survival than men. The incidence of adenocarcinoma significantly decreased from 13.56 per 100,000 in 1996 to 9.82 per 100,000 in 2013 (P < 0.0001). In contrast, the incidences of mucosa-associated lymphoid tissue lymphoma and diffuse large B-cell lymphoma did not decrease. The incidence of adenocarcinoma and lymphoma, both of which are associated with H. pylori, showed diverging trends. The survival of gastric cancer differed by histologic subtype and sex. The disparity in the incidence trends between gastric lymphoma and adenocarcinoma, both associated with H. pylori, warranted the need to search for additional risk factors of gastric lymphoma.

Highlights of This Issue

The American Indian and Alaska Native (AI/AN) population bears a disproportionate burden of cancer incidence in the United States. To describe cancer incidence rates and trends in the AI/AN population compared with the non-Hispanic white population, Melkonian and colleagues used data from the central cancer registries linked with the Indian Health Service patient registration databases to identify cancers diagnosed between 2010 and 2015. The authors reported elevated rates of lung, colorectal, liver, kidney, and stomach cancer in the AI/AN population that varied by geographic region. This confirmed widening cancer disparities and highlighted missed opportunities for targeted interventions to reduce AI/AN cancer incidence.Over the last two decades, there has been a rise in head and neck cancers in the oropharynx, due to the human papillomavirus (HPV). These cancers require aggressive treatment with radiation, surgery, or chemotherapy. This study by Mahal and colleagues is the largest study to date on the incidence of HPV-positive oropharyngeal head and neck squamous cell carcinoma in the United States, finding that 75% of oropharynx cancers are related to HPV. The U.S. incidence of HPV-related throat cancer is 4.6 per 100,000 people, peaking amongst those ages 60 to 64, and highest in white men where it is the 6th most common incident nonskin cancer. The study shows that the favorable prognosis associated with Hp. is restricted to oropharynx cancer rather than other head and neck cancers and provides data to support education and prevention strategies, including vaccination.Helicobacter pylori (H. pylori) eradication has been shown to decrease gastric adenocarcinoma risk. The epidemiology of gastric lymphoma, which is also associated with H. pylori, and other rare subtypes of gastric cancer is less clear. This study by Chang and colleagues comprehensively evaluated the incidence trend and the survival of gastric cancer in Taiwan by histologic subtype. The incidence trends of gastric cancer in Taiwan from 1996 to 2013 were evaluated using data from the Taiwan Cancer Registry. The incidence of all gastric cancers in Taiwan decreased. However, the incidence of adenocarcinoma and lymphoma, both of which are associated with H. pylori, showed diverging trends. The disparity in the incidence trends warrants the need to search for additional risk factors of gastric lymphoma.The etiology of intrahepatic cholangiocarcinoma (ICC) is less well- known compared to hepatocellular carcinoma (HCC). As ICC has poor prognosis and response to conventional therapy, identifying diagnostic and prognostic biomarkers of this form of liver cancer is warranted. Liquid chromatography coupled to tandem mass spectrometry was used to measure non-invasively detected urinary metabolites in subjects from the U.S. (NCI-MD cohort) and Thailand (TIGER-LC cohort). Haznadar and colleagues found that metabolites were significantly increased in both, HCC and ICC in urine, but were significantly higher in ICC in urine and in tissue. Metabolite profile was robust at classifying ICC in combination with a clinically utilized marker, CA19-9, holding promise for diagnostic and prognostic evaluation of ICC.

Time Trends And Age-Period-Cohort Effects On The Incidence Of Gastric Cancer In Changle From 2003 To 2012.

PurposeAlthough the incidence of gastric cancer in China has declined over the past decades, they were still much higher than the average of global. This aim of this study was to describe the trends and age-period-cohort effects on gastric cancer incidence from 2003 to 2012 in Changle and to explore the potential reason.Materials and methodsData on patients with gastric cancer diagnosed between 2003 and 2012 were collected by the population-based Changle cancer registration (n=4111). Age-standardized incidence rates of gastric cancer were calculated and joinpoint regression was used to evaluate the trends of gastric cancer incidence. Time trends in gastric cancer incidence by the period of diagnosis and birth cohort were analyzed by sex. Age-period-cohort analysis was performed to investigate the independent effects of age, period of diagnosis and birth cohort among over 25-year-old residents.ResultsA steady downward trend was observed among men, with the incidence ranging from 96.15 per 100,000 in 2003 to 62.6 per 100,000 in 2012 (APC, −5.1%; 95% CI: −6.9 to −3.2%). A similarly declining trend was observed among women with the incidence ranging from 34.5 per 100,000 to 15.7 per 100,000 (APC, −5.7%; 95% CI: −9.3 to −2.0%). Age-period-cohort model of incidence rate showed increasing age effect and decreasing period of diagnosis effects in both men and women. Birth cohorts exhibited a decreasing trend in the incidence among women who were born after 1935 and men after 1940.ConclusionRecent decreases in the incidence of gastric cancer were due to decreased period of diagnosis and cohort effects, which was attributed to the improvements in their lifestyle and habits.

Trends in Gastric Cancer Incidence According to the Clinicopathological Characteristics in Korea, 1999-2014.

PurposeThe aim of this study was to evaluate recent trends in gastric cancer incidence according to the age, sex, and tumor location in the Korean population. Materials and MethodsUsing data from the Korea Central Cancer Registry between 1999 and 2014, gastric cancer incidence, annual percent changes, and male-to-female incidence rate ratios (IRRs) according to tumorlocationwere determined. The distribution of disease extent according to the tumor location and its changes between 2006 and 2014 were also analyzed.ResultsIncidence of gastric cancer was stable until 2011 and decreased between 2011 and 2014. The age-standardized incidence rate of gastric cancer was 43.6 (per 100,000) in 1999 and 35.8 in 2014. The proportion of cardia/fundus cancer remained stable (5.9% to 7.1%), and that of body cancer increased (35.3% to 43.2%). The male-to-female IRR decreased in most age groups, except for those in their 60s. In the distribution of disease extent, the proportion of localized disease increased, and regional and distant disease decreased in all tumor locations (53.9% to 66.0%, 31.4% to 22.5%, and 14.8% to 11.5%, respectively; p < 0.001). For histological type, the proportion of carcinoid tumor and non-epithelial tumor increased (0.3% to 1.0%, and 0.8% to 1.4%, respectively). ConclusionIn the 15 years from 1999 through 2014, age-standardized incidence of gastric cancer started to decrease from 2012, and the proportion of cardia/fundus cancer remained unchanged. The trend of increasing localized cancer was observed in all tumor locations.

Changing Trends in Stomach Cancer Throughout the World.

The paper aims to discuss the global trends in gastric cancer incidence in relation to important factors involved in the pathogenesis of gastric cancer. Despite a significant worldwide decline, gastric cancer remains a common cause of cancer death. The decline has been multifactorial and preceded the fall in Helicobacter pylori prevalence. The initial decline was associated with changes in food preservation and availability, especially of fresh fruits and vegetables, followed by a decline in the primary etiologic factor, H. pylori. Gastric cancer incidence remains high in East Asia, intermediate in Latin America, and low in developed countries. Significant racial/ethnic variability exists. The rapid decline in incidence in East Asia will continue as primary and secondary prevention strategies are implemented. The incidence in Latin America is unlikely to decline significantly over the next few decades given high H. pylori prevalence in the young. Ultimately, global H. pylori eradication will be needed to largely eliminate gastric cancer.

A rising trend in the incidence of advanced gastric cancer in young Hispanic men.

Although the incidence of gastric cancer has been decreasing, recent reports suggest an increased rate in select populations. We sought to evaluate trends in gastric cancer incidence to identify high-risk populations. Gastric cancer incidence rates from 1992 to 2011 were computed with use of the Surveillance, Epidemiology, and End Results (SEER) registry. We evaluated trends in incidence rates by calculating the annual percent change (APC) across three age groups (20-49years, 50-64years, and 65years or older) and four racial/ethnic groups (Hispanics, non-Hispanic whites, blacks, and Asian/Pacific Islanders). We identified 41,428 patients with gastric cancer. For the entire cohort during the study period, the APC was decreased. When patients were grouped according to sex, the APC was flat or decreased in women regardless of age or race/ethnicity. The APC was also flat or decreased for all men except young Hispanic men (20-49years), who had an increased APC of nearly 1.6% (1.55%, 95% confidence interval 0.26-2.86%). Furthermore, young Hispanic men were the only group to have increased incidence of stageIV disease (APC 4.34%, 95% confidence interval 2.76-5.94%) and poorly differentiated tumors (APC 2.08%, 95% confidence interval 0.48-3.70%). The APC of the incidence of gastric cancer in young Hispanic men places it among the top cancers with rising incidence in the USA. This is concomitant with increased incidence of advanced disease at presentation. This major public health concern warrants additional research to determine the cause of the increasing incidence in this group.

Trends in gastric cancer incidence: a period and birth cohort analysis in a well-defined French population.

The incidence of gastric cancer has declined over the past decades. Little is known about trends by site and histological subtype. The aim of this study was to analyze changes in gastric cancer incidence patterns in a French well-defined population. Data on patients with an epithelial gastric cancer diagnosed between 1982 and 2011 were collected by the population-based digestive cancer registry of Burgundy (n = 4694). Time trends in gastric cancer incidence by period of diagnosis and birth cohort were analyzed by sex, subsite, and histological type. There was a decrease in incidence rates for antral carcinomas (-2.6 % per year in males, -2.5 % per year in females; p < 0.001) and corpus carcinomas (-3.3 % and -3.2 %, respectively; p < 0.001). Annual percentage changes were not significant for fundus carcinomas in both sexes and cardia carcinoma in females, although they increased in males (+1.0 % per year; p < 0.02).When comparing the 1900 cohort and the 1950 cohort, there was a five- to sevenfold decrease in the cumulative risk at 0-79 years for corpus and antral carcinomas in both sexes and a threefold decrease for fundus carcinomas. There were minor variations for cardia carcinomas. There was a decrease of incidence both by period of diagnosis and by birth cohort for adenocarcinoma and colloid carcinoma. It was more marked for undifferentiated carcinoma. The variation for signet-ring carcinoma was minor. Temporal variations in incidence rates of gastric cancer differed according to subsite and histology, suggesting different etiological factors. Available analytical studies provide an explanation for the reported trends by subsite.

Gastric cancer in young patients: Clues on a possible separate entity requiring a watchful approach

See article in J. Gastroenterol. Hepatol. 2011; 26: 1626–1629.

Trends in oesophago-gastric cancer incidence in Spain: analysis by subsite and histology

Background: During recent decades, an increase in the incidence of certain oesophago-gastric cancer subtypes has been reported in some countries. This study sought to analyse oesophageal and gastric cancer incidence trends in Spain by sex, site and morphology for the period 1980–2004.Patients and methods: Oesophageal and gastric cancer cases were drawn from 13 Spanish population-based cancer registries. Time trends in sex- and age-standardised cancer incidence rates were analysed by subsite and histology over the study period, using change-point Poisson models.Results: Age-standardised oesophageal cancer incidence rates failed to register a significant trend over the study period. Overall, gastric cancer decreased from 27.21 and 13.44 cases per 100 000 person-years in 1980–84 to 20.21 and 8.68 in 2000–04, among men and women, respectively. Whereas oesophageal adenocarcinomas increased by ∼5% per annum in both sexes, gastric cardia cancer increased during the study period in males only, though this increase was less pronounced. Among men, oesophageal squamous cell cancer and non-cardia cancer rates declined steadily from the mid-1980s onwards. Over the same period, there was a marked decrease in the incidence of oesophago-gastric cancer presenting with unspecified subsite or morphology.Conclusions: Changes in the prevalence of the main risk factors for these tumours might only partly explain oesophageal and gastric cancer rate trends by subtype. Reclassification, however, would appear to account for most of the divergence in oesophageal and gastric cancer trends by subtype over the study period.

Trends in gastric cancer incidence in a well-defined French population by time period and birth cohort.

Epidemiological studies have shown a marked decline in gastric cancer incidence and opposite patterns between proximal and distal sites among different populations. Little is known about trends by histological type. The aim of this study was to analyse the change in gastric cancer incidence patterns by investigating the role of temporal components as determinants of such trends in the population of the Côte d'Or area (France) registered between 1976 and 1995. Gastric cancer incidence decreased over time. There was a decrease in incidence rates for distal cancers (-3.5% P < 0.001 per year in men and -4.6% P < 0.01 in women). In contrast, there was a non-significant increase of proximal cancer incidence in men and in women. Rates of adenocarcinomas decreased, whereas the incidence rates of undifferentiated carcinomas and of other histological types remained quite stable. There was a decrease in cumulative risk throughout the studied cohorts, whereas risk for proximal cancer remained stable and decreased slightly for distal localization. For adenocarcinomas, earlier birth cohorts showed a slight decrease in rates, whereas there was an increase for recent cohorts. Subsite and histological-specific analysis, in revealing different time trends in incidence, suggest, at least partly, different aetiologies for gastric cancer, and future aetiological studies must distinguish proximal and distal cancers.

Time trend and age-period-cohort effects on gastric cancer incidence in Zaragoza and Navarre, Spain.

STUDY OBJECTIVE: To describe time trends in gastric cancer incidence in Zaragoza and Navarre, and to investigate time period and birth cohort as determinants of such trends. DESIGN: Cases from...