Secular trends in the incidence, mortality, and survival rate of gastric cancer in a general Japanese population: the Hisayama study

Epidemiology of stomach cancer

Despite a decline in incidence and mortality during the last decades, stomach cancer is one of the main health challenges worldwide. According to the GLOBOCAN 2020 estimates, stomach cancer caused approximately 800000 deaths (accounting for 7.7% of all cancer deaths), and ranks as the fourth leading cause of cancer deaths in both genders combined. About 1.1 million new cases of stomach cancer were diagnosed in 2020 (accounting for 5.6% of all cancer cases). About 75% of all new cases and all deaths from stomach cancer are reported in Asia. Stomach cancer is one of the most lethal malignant tumors, with a five-year survival rate of around 20%. There are some well-established risk factors for stomach cancer: Helicobacter pylori infection, dietary factors, tobacco, obesity, and radiation. To date, the most important way of preventing stomach cancer is reduced exposure to risk factors, as well as screening and early detection. Further research on risk factors can help identify various opportunities for more effective prevention. Screening programs for stomach cancer have been implemented in a few countries, either as a national or opportunistic screening of high-risk individuals only. Generally, due to its high aggressiveness and heterogeneity, stomach cancer still remains a severe global health problem.

Cancer Incidence and Mortality in Asian Countries: A Trend Analysis

Background

This study aimed to evaluate the updated burden and temporal trends of cancer incidence and mortality in Asian countries.

Methodology

The data used in this study were retrieved from the Global Cancer Observatory, Cancer Incidence in Five Continents volumes I-XI, and the World Health Organization mortality database. These data were used to calculate the Average Annual Percentage Change (AAPC), with a 95% confidence interval (CI) by joinpoint regression analysis to determine the epidemiological trend in the past decade.

Results

In 2020, the cancer incidence in Asia was 169.1 per 1 00 000, accounting for 49.3% of the global cancer incidence. The most common cancers included lung (13.8%), breast (10.8%) and colorectal (10.6%) cancers. Its mortality was 101.6 per 1 00 000 (58.3% of the global cancer death) with lung (19.2%), liver (10.5%) and stomach (9.9%) cancers being the most common causes of cancer death. The cancer incidence had been increasing in female population, with Korea (AAPC = 5.73, 95% CI [5.30, 6.17], P < .001), Japan (AAPC = 2.67, 95% CI [2.12, 3.23], P < .001) and Kuwait (AAPC = 2.08, 95% CI [.49, 3.69], P = .016) showing the most significant increases in the past decade. The incidence increase was also observed among population aged <40 years old, with Korea (female AAPC = 8.42, 95% CI [7.40, 9.45], P < .001; male AAPC = 5.28, 95% CI [4.23, 6.33], P <.001), China (female AAPC = 2.94, 95% CI [2.07, 3.81], P < .001; male AAPC = 1.37, 95% CI [.57, 2.18], P = .004) and Japan (female AAPC = 2.88, 95% CI [1.88, 3.88], P = .016; male AAPC = 1.59, 95% CI [.40, 2.78], P = .015) showing the most significant increases. However, there was an overall decreasing trend of cancer mortality.

Conclusions

There was a substantial burden of cancer incidence and mortality in Asia. Although there was a decreasing trend in cancer mortality, its incidence had been increasing especially among female and younger populations. Future studies could be done to further investigate the potential reasons for these epidemiologic trends.

The Clinicopathological Features and Staging at Presentation of Gastric Cancer: A Single-Center Retrospective Study

Introduction Gastric cancer (GC) is the third leading cause of cancer death, with most patients diagnosed at a later stage, with distant metastasis at the time of presentation, contributing to poor prognosis. GC has been associated with nonspecific clinical presentations, which cause a time delay for patients to seek for medical advice. This study aims to identify the clinicopathological features of GC patients and correlate time delay of the diagnosis to the staging of the disease.

Materials and Methods This is a single-center retrospective study of GC patients diagnosed from January 2012 to December 2018. All relevant data of GC patient diagnosed during this time period were extracted from the patients’ case notes.

Results A total of 69 GC patients were included in this study, with male preponderance and mean age of 62 years old. The top three symptoms presented are dyspepsia or ingestion (47.8%), weight loss (43.5%), and nausea or vomiting (33.3%). The mean time delay was 3.7 months. Patients presented with weight loss have a significantly longer average time delay of 4.88 months. Most tumor lesion was found at the distal stomach (43.5%), while 74.5% tested negative for Helicobacter pylori. Most patients were diagnosed at Stage IV (52.6%) and Stage III (36.8%) of the disease, with poorly differentiated (67.7%) histological features which have poor prognosis.

Discussion and Conclusion No evidence of specific symptom or combination of symptoms predicts higher risk of GC. Regardless of the number of symptoms presented or the time delay, most GC patients were diagnosed at later stage of the disease. The study shows the importance of GC screening in Malaysia to ensure early detection, even before a symptom presented.

Second primary malignancy risk among patients with gastric cancer: a nationwide population-based study in Taiwan

BACKGROUND

Several studies have reported an increase in second primary malignancies (SPMs) among gastric cancer patients.

METHODS

Patients who were newly diagnosed with gastric cancer between 1997 and 2011 were recruited from the Taiwan National Health Insurance database. Those who had antecedent malignancies or gastrointestinal stromal tumor were excluded. Standardized incidence ratios (SIRs) of SPMs were calculated. Risk factors for cancer development were analyzed by Cox proportional hazards models. Effects of treatments for gastric cancer were treated as time-dependent variables.

RESULTS

During the 15-year study period, 47,729 gastric cancer patients were recruited. Overall, 2,110 SPMs developed during a total follow-up of 137,798 person-years. The SIR for all cancers was 1.46. The SIRs for specific follow-up periods were 1.43, 1.41, and 1.21 at >10 years, 5-10 years, and 1-5 years, respectively. After excluding SPMs that developed within 1 year, significantly higher SIRs were seen for cancers of the head and neck (1.34), esophagus (2.16), colon and rectum (1.37), bones and soft tissues (1.95), ovaries (2.89), bladder (1.47), or kidneys (1.44), as well as non-Hodgkin's lymphoma (5.56). Multivariate analysis showed that age ≥70 years [hazard ratio (HR) 1.19], being male (HR 1.37), diabetes mellitus (HR 1.30), chronic obstructive pulmonary disease (HR 1.17), and liver cirrhosis (HR 1.94) were independent risk factors. Radiotherapy (HR 1.24) and chemotherapy (HR 1.87) were independent risk factors, but surgery (HR 0.67) was not.

CONCLUSIONS

Patients with gastric cancer are at increased risk of developing SPM. Close surveillance of patients with risk factors over a longer period should be considered.

Preexisting Diabetes and Risks of Morbidity and Mortality After Gastrectomy for Gastric Cancer: A Nationwide Database Study

The purpose of this study was to determine the risk of surgical mortality and morbidity in patients with diabetes mellitus (DM) undergoing a gastrectomy for gastric cancer (GC). Using the Taiwan National Health Insurance Research Database, we identified 6284 patients who underwent gastrectomy for GC from 1999 to 2010. In addition, we created a non-DM control cohort consisting of 6268 patients who received gastrectomy during the same period. Compared with the non-DM cohort, the DM cohort exhibited a higher prevalence of preoperative coexisting medical conditions, namely hypertension, hyperlipidemia, coronary artery disease, chronic kidney disease, chronic pulmonary disease, stroke, and cirrhosis. The odds ratio (OR) of 30-day postoperative mortality after gastrectomy in the DM cohort was 1.04 (95% confidence interval 0.78-1.40) after we adjusted for covariates. The DM cohort did not exhibit a significantly higher risk of 30-day postoperative morbidities. Further analysis revealed that only patients with a history of a DM-related coma exhibited a higher risk of 30-day postoperative mortality (adjusted OR 2.46, 95% confidence interval 1.10 - 5.54). Moreover, the risk of 90-day postoperative mortality was significantly higher in patients with DM-related eye involvement, coma, peripheral circulatory disease, and renal manifestations, in comparison with the non-DM cohort. The risk of 90-day mortality after gastrectomy for GC is higher in patients with DM-related manifestations than those without DM.

Trends of stomach cancer mortality in Eastern Asia in 1950-2004: comparative study of Japan, Hong Kong and Singapore using age, period and cohort analysis

To characterize the temporal trends of stomach cancer mortality in Eastern Asia and to better interpret the causes of the trends, we performed age, period and cohort analysis (APC analysis) on the mortality rates in Japan, Hong Kong and Singapore during 1950-2004, as well as the rates in the US as a control population. For the APC analysis, Holford's approach was used to avoid the identification problem. Age-standardized mortality rates (ASMR) decreased consistently in all four areas during the observation period in both males and females. Japan had the highest ASMR in both sexes, followed by Singapore, Hong Kong and the US, but the differences in ASMR among the four areas diminished with time. The results of APC analysis suggested that the decreasing mortality rates in Eastern Asia were caused by the combination of decreasing cohort effect since the end of the 1800s and decreasing period effect from the 1950s. The US showed similar results, but its decreases in the period and cohort effect preceded those of Eastern Asia. Possible causes for the decrease in the cohort effect include improvement in the socioeconomic conditions during childhood and a decrease in the prevalence of H. pylori infection, while possible causes for the decrease in the period effect include a decrease in dietary salt intake and improvements in cancer detection and treatment. These findings may help us to predict future changes in the mortality rates of stomach cancer.

Lauriston S. Taylor lecture: Radiation Protection and Public Policy in an Uncertain World

Ionizing radiation is a known, well-documented, and reasonably well-quantified human cancer risk factor based on a remarkably consistent body of dose-response information from epidemiological studies of exposed populations supported by experimental studies using animal and cellular models. This fact is largely ascribable to the relative ease, compared to other carcinogens, of estimating radiation dose to organs and local tissues. Statistical models for radiation-related cancer risk are increasingly relevant to both radiation protection policy and the adjudication of compensation claims for cancers diagnosed following occupational and environmental exposures to ionizing radiation, as discussed in a number of expert committee reports of national and international organizations concerned with radiation-related risks. These and other publications increasingly emphasize the relevance of well-quantified uncertainties in radiation-related risk projections, including upper and lower confidence or uncertainty bounds, for radiation protection. Finally, the wealth of detailed information provided by such quantitative uncertainty analysis approaches is highly relevant to radiation protection, which might be viewed as a political process that involves a diverse group of stakeholders who, individually, may be primarily concerned with avoiding possible radiation-related risks or with avoiding possibly unnecessary costs of risk reduction or unnecessary denial of benefits that require some radiation exposure, or with balancing both considerations to some degree.

Absence of CD71 transferrin receptor characterizes human gastric adenosquamous carcinoma stem cells

BACKGROUND

Although the importance of cancer stem cells (CSCs) in overcoming resistance to therapy and metastasis has recently been reported, the role of CSCs in gastric cancer remains to be elucidated.

METHODS

MKN-1 cells were used to study markers of CSCs in gastric adenosquamous carcinoma, as these cells are suitable for determining multidifferentiation ability. Changes in expression of CD44, CD49f, CD133, and CD71 following 5-fluorouracil (5-FU) treatment were assessed.

RESULTS

After 5-FU treatment, only the CD71- fraction was significantly increased. Investigation of CD71 indicated that the CD71- cell fraction was present in the G1/G0 cell cycle phase and showed high resistance to the anticancer agent 5-FU. Limiting dilution and serial transplantation assays revealed the CD71- cell fraction to have higher tumorigenicity than the CD71+ cell fraction. The CD71- cell fraction showed multipotency to adenocarcinoma and squamous cell carcinoma. A three-dimensional (3D) invasion assay and immunohistochemical analysis showed CD71- cells to be highly invasive and to exist in the invasive fronts of cancer foci.

CONCLUSION

The present study suggests that use of CD71- as a marker for adenosquamous carcinoma may provide a useful model for studying CSCs.

Association between PARP-1 polymorphisms and susceptibility to gastric cancer

AIM: To investigate the association between the Val762Ala and Lys940Arg polymorphisms of the poly(ADP-ribose) polymerase-1 (PARP-1) gene and susceptibility to gastric cancer in a Chinese Han population in He'xi area of Gansu Province.

METHODS: All investigated subjects were divided into two groups: 150 gastric cancer patients and 152 controls. The SNaPshot single nucleotide polymorphism (SNP) genotyping method was used to analyze the genotypes of PARP-1 Val762Ala and Lys940Arg. Helicobacter pylori (H.pylori) IgG antibody was detected by enzyme-linked immunosorbent assay (ELISA). The results were analyzed using the SPSS16.0 software package.

RESULTS: PARP-1 940 Lys/Arg and 762 Val/Ala genotypes were overrepresented in gastric cancer patients compared with controls (OR = 2.917 and 1.685; 95%CI: 1.430-5.947 and 1.040-2.729; P = 0.002 and 0.034, respectively). In smoking subjects, the risk of gastric cancer in PARP-1 940 Lys/Arg genotype carriers was 8.430-fold higher than that in Lys/Lys carriers (OR = 8.340, 95%CI: 2.664-26.144, P = 0.000). In drinking subjects, PARP-1 940 Lys/Arg genotype carriers had a 3.333-fold higher risk of gastric cancer than Lys/Lys carriers (OR = 3.333, 95%CI: 1.214-9.155, P = 0.015). In H.pylori IgG-positive subjects, PARP-1 762 Ala/Ala genotype carriers had a 2.360-fold increased risk of gastric cancer than Val/Val carriers (OR = 2.360, 95%CI: 1.256-4.433, P = 0.007). The subjects carrying PARP-1 940 Lys/Arg and PARP-1 Ala/Ala or Val/Ala genotypes had a 4.2-fold increased risk of gastric cancer compared with those carrying PARP-1 940 Lys/Lys and PARP-1 762Val/Val genotypes (OR = 4.200, 95%CI: 1.430-12.338, P = 0.006).

CONCLUSION: PARP-1 940Lys/Arg and PARP-1 762Ala/Ala or Ala/Ala genotypes are associated with a higher risk of gastric cancer. There are multiplicative joint effects between PARP-1 940 Lys/Arg genotype and smoking or drinking, between PARP-1 762 Val/Ala or Ala/Ala genotypes and H.pylori infection, and between PARP-1 Lys940Arg and PARP-1 Val762Ala genotypes in increasing the risk of gastric cancer.

Recent patterns in gastric cancer: a global overview

Until the mid-1990s, gastric cancer has been the first cause of cancer death worldwide, although rates had been declining for several decades and gastric cancer has become a relatively rare cancer in North America and in most Northern and Western Europe, but not in Eastern Europe, Russia and selected areas of Central and South America or East Asia. We analyzed gastric cancer mortality in Europe and other areas of the world from 1980 to 2005 using joinpoint regression analysis, and provided updated site-specific incidence rates from 51 selected registries. Over the last decade, the annual percent change (APC) in mortality rate was around -3, -4% for the major European countries. The APC were similar for the Republic of Korea (APC = -4.3%), Australia (-3.7%), the USA (-3.6%), Japan (-3.5%), Ukraine (-3%) and the Russian Federation (-2.8%). In Latin America, the decline was less marked, but constant with APC around -1.6% in Chile and Brazil, -2.3% in Argentina and Mexico and -2.6% in Colombia. Cancers in the fundus and pylorus are more common in high incidence and mortality areas and have been declining more than cardia gastric cancer. Steady downward trends persist in gastric cancer mortality worldwide even in middle aged population, and hence further appreciable declines are likely in the near future.

Population-based prospective study of the combined influence of cigarette smoking and Helicobacter pylori infection on gastric cancer incidence: the Hisayama Study

The authors assessed the separate and joint influences of cigarette smoking and Helicobacter pylori infection on the development of gastric cancer in a population-based prospective study. A total of 1,071 Japanese men aged > or =40 years were followed up prospectively for 14 years (1998-2002). Compared with that for current nonsmokers, the multivariate-adjusted hazard ratios of gastric cancer for smokers of 1-9, 10-19, and > or =20 cigarettes per day were 1.36 (95% confidence interval (CI): 0.50, 3.71), 1.93 (95% CI: 1.01, 3.67), and 1.88 (95% CI: 1.02, 3.43), respectively. The risk of gastric cancer increased steeply for subjects who had both a smoking habit and H. pylori infection compared with those who did not have both risk factors (hazard ratio = 11.41, 95% CI: 1.54, 84.67). If causal, the estimated population attributable fraction of gastric cancer for cigarette smoking was approximately half that for H. pylori infection (28.4% vs. 56.2%). The overlap of the population attributable fractions for the 2 factors was 49.6%. Findings suggest that cigarette smoking and H. pylori infection are significant risk factors for gastric cancer in Japanese men, and the magnitude of their combined influence is considerable.