Attributable causes of cancer in Japan in 2005--systematic assessment to estimate current burden of cancer attributable to known preventable risk factors in Japan

Clinical features and risk factors of gastric cancer detected by esophagogastroduodenoscopy in esophageal cancer patients

BACKGROUND

Gastric cancer is the most frequent primary cancer-associated with esophageal cancer and is most commonly detected by endoscopic surveillance. However, the clinical features of synchronous or metachronous gastric cancer that could be detected by esophagogastroduodenoscopy in esophageal cancer patients are unknown.

METHODS

We reviewed the clinical records of all esophageal cancer patients (n = 1379) registered in the cancer registration database who underwent initial treatment between April 2010 and October 2015. We retrospectively analyzed the proportions of synchronous and metachronous gastric cancer cases, the cumulative incidence rate of metachronous gastric cancer in total and by esophageal cancer treatments (endoscopic resection, esophagectomy, and chemoradiotherapy), and the clinical features of esophageal cancer patients with synchronous or metachronous gastric cancer.

RESULTS

Overall, 67 (5.3% of 1275) esophageal cancer patients with synchronous gastric cancer and 40 (5.1% of 791) esophageal cancer patients with metachronous gastric cancer were analyzed. The 5-year cumulative incidence rate of metachronous gastric cancer was 5.6% in total, 7.8% after endoscopic resection, 4.7% after esophagectomy, and 4.1% after chemoradiotherapy for esophageal cancer. From the results of multivariate analysis, the risk factors for synchronous gastric cancer were male (odds ratio 13.3) and moderate/severe atrophic gastritis (odds ratio 17.9), and the risk factor of metachronous gastric cancer was moderate/severe atrophic gastritis (hazard ratio 27.6) in patients with esophageal cancer.

CONCLUSIONS

The incidence rates of synchronous and metachronous gastric cancer with esophageal cancer were both over 5%. Careful endoscopic observation is required for moderate and severe atrophic gastritis at detecting concomitant gastric cancer in esophageal cancer patients.

A newly developed aerosol exposure apparatus for heated tobacco products for in vivo experiments can deliver both particles and gas phase with high recovery and depicts the time-dependent variation in nicotine metabolites in mouse urine

INTRODUCTION

There is no standardized aerosol exposure apparatus to deliver heated tobacco products (HTPs) for in vivo experiments. Therefore, we developed a novel HTPs aerosol exposure apparatus for mice and demonstrated that nicotine and other chemicals in HTPs aerosol generated by the apparatus can be delivered to mice which replicate human smoke.

METHODS

The amounts of nicotine, tar, and carbon monoxide (CO) in IQOS (Marlboro Regular HeatSticks™) aerosol generated by two types of apparatuses were determined. C57BL/6N mice were exposed to IQOS aerosol, followed by determination of the urinary nicotine metabolites. Further, the skin surface temperature of mice was monitored to confirm the vasoconstriction action of nicotine.

RESULTS

The amounts of chemicals in IQOS aerosol by the novel air push-in inhalation apparatus for HTPs (APIA) was equivalent to that of the analytical vaping machine (LM4E) [1.60 ± 0.08 (APIA) vs 1.46 ± 0.07 mg/stick (LM4E) in nicotine and 0.55 ± 0.04 (APIA) vs 0.45 ± 0.01 mg/stick (LM4E) in CO]. After mice were exposed to IQOS aerosol by APIA, the urinary nicotine metabolites levels were determined; peak values in cotinine and 3-hydroxycotinine were 6.82 μg/mg creatinine at 1 h after exposure and 32.9 μg/mg creatinine at 2 h after exposure, respectively. The skin surface temperature decreased and was lower (33.5°C ± 0.5°C) at 30 min than before exposure (37.6°C ± 0.8°C).

CONCLUSIONS

The new apparatus for HTPs aerosol exposure to mice showed good performances in terms of both chemical analysis of collected aerosol and fluctuations in the urinary nicotine metabolites.

Trends and differences in alcohol-related mortality rates by gender and by prefectures in Japan between 1995 and 2016

BACKGROUND

This study aimed to identify increases in 100 % alcohol-related death (ARD) and any differences among prefectures between 1995-2016.

METHODS

Data from the national death registry on 100 % ARDs between 1995-2016 were extracted. Age-standardized mortality rate (ASMR) of 100 % ARD by year, gender, and gender ratio were calculated. After dividing the period into 1995-2005 and 2006-2016, the ASMRs of 100 % ARDs were calculated by prefecture. Additionally, based on geographical area, municipality size, or annual alcohol sales per adult in each prefecture, prefectures were divided into groups and analysed.

RESULTS

In total, 95,455 deaths were caused by 100 % ARD from 1995-2016. Men's ASMRs of 100 % ARD markedly increased from 4.0 per 100,000 in 1995 to 5.2 between 2010 and 2013, and gradually declined to 5.0 in 2016. Women's ASMRs increased steadily from 0.3 in 1995 to 0.8 in 2016. The gender ratio of ASMRs decreased from 13.3 in 1995 to 6.3 in 2016. The ASMR of one prefecture, which had reduced alcohol tax rates, was higher for both genders. Both men's and women's ASMRs were higher in the prefectures that had higher alcohol sales (6.3 [5.0-7.7] and 0.8 [0.6-1.1], respectively) compared to the prefectures that had lower alcohol sales (4.3 [4.0-4.7] p < 0.001 and 0.6 [0.5-0.6] p = 0.045, respectively).

CONCLUSIONS

The ASMR of 100 % ARD remained high for men and increased for women, and prefecture-level higher alcohol sales and lower tax rates correlated with the higher mortality rate. Increasing prices and taxes and reducing alcohol sales may contribute to a decrease in alcohol-related mortality.

Effectiveness of a Cancer Risk Prediction Tool on Lifestyle Habits: A Randomized Controlled Trial

BACKGROUND

Risk prediction models offer a promising approach to lifestyle modification. We evaluated the effect of personalized advice based on cancer risk prediction in improving five lifestyle habits (smoking, alcohol consumption, salt intake, physical activity, and body mass index) compared with standard advice without risk prediction among a Japanese general population with at least one unhealthy lifestyle habit.

METHODS

In a parallel-design, single-blind, randomized controlled trial between February 2018 and July 2019, 5984 participants aged 40-64 years with unhealthy lifestyle habits were recruited from persons covered under a life insurance policy. They were randomly assigned to an intervention or control group and received personalized or standard advice, respectively. They were also sent an invitation to participate in a lifestyle modification program aimed at improving lifestyle. Primary outcome was an improvement in lifestyle, defined as an increase in healthy lifestyle habits within 6 months.

RESULTS

The proportion of participants who improved their lifestyle within 6 months in the intervention group did not significantly differ from that in the control group (18.4% vs. 17.7%; P = 0.488). Among participants with low health literacy and two or fewer of five healthy habits, the proportion of participants subscribing to the lifestyle modification program was higher in the intervention group than in the control group.

CONCLUSIONS

Compared with standardized advice, personalized advice based on cancer risk prediction had no effect on improving lifestyle.

IMPACT

Provision of predicted cancer risk information did not induce change in unhealthy lifestyle.

Burden of cancers attributable to modifiable risk factors in Malaysia

Background

This is a systematic assessment of the burden of cancers in Malaysia in 2018 using epidemiologic approach. The purpose of this study was to identify the proportion of cancers in Malaysia that were attributable to the modifiable risk factors of excess weight, alcohol intake, physical inactivity, tobacco smoking and to estimate the number of cancer cases that could be prevented if the exposure to the modifiable risk factor was reduced.

Methods

We estimated the Population Attributable Fraction (PAF) of the modifiable risk factors to cancers incidences in Malaysia. The two parameters used for the estimation were exposure prevalence from national representative surveys and the relative risk of getting the cancers from worldwide literature review.

Results

Among 38,426 cancer incidences in 2018 from Globocan data, we estimated that 22.2% (95% confidence interval (CI):14.9 to 29.6%) of the cancer incidences included in this study were attributable to the investigated modifiable risk factors. 39.1% (95% CI:27.2 to 49.7%) and 10.5% (95% CI:5.8 to 15.7%) of cancers in male and female respectively, were attributable to the studied modifiable risk factors. The top main cancers attributed by the risk factors were lung cancer (65.1%; 95% CI:56.4 to 72.9%), laryngeal cancer (63.6%; 95% CI:39.9 to 80.5%), and oesophageal cancer (51.5%; 95% CI:39.9 to 62.0%). For each risk factor studied across genders, tobacco smoking contributed the most (14.3%; 95% CI:9.9 to 17.3%), followed by excess weight (7.0%; 95% CI:4.1 to 10.2%), physical inactivity (1.0%; 95% CI:0.4 to 1.7%) and alcohol intake (0.6%; 95% CI:0.2 to 1.0%).

Conclusion

Findings from this study suggests that tobacco smoking and excess weight are the two predominant factors out of the four studied risk factors for cancer cases in Malaysia. Nationwide public health prevention campaigns tailored to these risk factors are recommended. However, the other risk factors such as physical inactivity and alcohol intake shall not be neglected. PAFs are estimated based on the best available data that we have currently. Regular collection of other risk factor exposure prevalence data is vital for future analyses.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-021-10412-9.

Socioeconomic Disparities in All-Cause and Cause-Specific Mortality Rates among Municipalities in Japan, 1999-2019

Differences in all-cause and cause-specific mortality rates depending on municipal socioeconomic status (SES) in Japan have not been revealed over the last 20 years. This study exposes the difference in 1999 and 2019 using the Vital Statistics. All of the municipalities were grouped into five quintiles based on their SES, and standardized mortality ratio (SMR) of each municipal quintile compared with all of Japan was calculated for all-cause mortality and representative cause of deaths. As a result, although SMR for all-cause mortality for women tended to be lower in low SES quintiles in 1999, the reverse phenomenon was observed in 2019. Additionally, although SMR for all-cause of mortality for men was the lowest in the highest SES quintiles already in 1999, the difference in the SMR for all-cause mortality rates between the lowest and highest SES quintiles increased in 2019. The improvement of the SMR in the highest SES quintile and the deterioration in the lowest was also observed in representative types of cancer, heart disease, stroke, pneumonia, liver disease, and renal failure for men and women. Therefore, this study indicates a disparity in mortality depending on municipal SES enlarged in the last 20 years.

Population Attributable Fraction of Established Modifiable Risk Factors on Colorectal Cancer in Korea

Purpose

We estimated the population attributable fraction (PAF) of established risk factors for colorectal cancer, to provide evidence for prioritizing cancer prevention policy.

Materials and Methods

The exposure prevalence was calculated by using data from the 2005 Korean National Health Examination Survey for tobacco smoking, alcohol consumption, obesity, physical inactivity, and meat intake. Risk estimates (relative risks) were selected from the published meta-analyses. Cancer incidence data from the Korea Central Cancer Registry were used to estimate the preventable number of colorectal cancer cases in 2015.

Results

The PAFs of the tobacco smoking, alcohol consumption, obesity, physical inactivity, and consumption of red and processed meat were as follows: 9.2%, 11.1%, 9.1%, 18.9%, and 10.1% for colon cancer and 21.8%, 12.3%, 3.5%, 5.3%, and 9.2% for rectal cancer among men; 1.0%, 1.3%, 2.7%, 12.3% and 9.2% for colon cancer and 1.7%, 2.3%, 0.8%, 7.2%, and 8.3% for rectal cancer among women. The PAFs of selected risk factors were 46.2% for colon and 42.4% for rectum among men, while 24.3% for colon and 18.9% for rectum among women. The attributable numbers of colon and rectal cancer to selected risk factors were 4,028 and 3,049 cases among men, respectively, while 1,644 and 778 cases among women in the year of 2015.

Conclusion

Changes in modifiable risk factors could prevent half of the colorectal cancer in the Korean population.

Manufacturing Industry Cancer Risk in Japan: A Multicenter Hospital-Based Case Control Study

Background:

It is well known that specific occupations can cause harm in developing malignant neoplasms. Chemical exposure is particularly high in the manufacturing industry and workers in this sector may face a higher occupational risk for cancer. We aimed to estimate inequalities in the risk of cancers related to occupational chemical exposure in various manufacturing categories.

Methods:

Using nationwide clinical inpatient data (1984−2017) in Japan, we undertook a multicenter, case-control study with regard to risks of developing cancers among various manufacturing industry categories. Using the food manufacturing industry as the reference group, odds ratios and 95% confidence intervals for each industry were estimated by conditional logistic regression, adjusted for sex, age, admission period, and the admitting hospital. Medical record summaries accounting for 89% of industrial categories with high odds ratios were collected to confirm diagnoses made on the basis of histology. We estimated industrial hazards based on the Pollutant Release and Transfer Register.

Results:

A reduced risk for some of common cancers was observed among lumber and wood products industries. Leather tanning, leather products and fur tended to show a higher risk: 2.36 (95% CI 1.15−4.83) for pancreatic cancer, 2.85 (95% CI 1.26−6.47) for liver cancer and 2.00 (95% CI 1.01–3.99) for lung cancer. For the electronics category, observations of high risk ranged from 2.09 (95%CI 1.18–3.70) for ureter cancer, to 2.49 (95% CI 1.79–3.55) for kidney cancer.

Conclusions:

This study revealed industry risk inequalities in manufacturing categories were present with regard to the risk of common cancers in Japan.

Human NINEIN polymorphism at codon 1111 is associated with the risk of colorectal cancer

NINEIN serves an essential role in centrosome function as a microtubule organizing center, and in the reformation of the interphase centrosome architecture following mitosis. In the present study, the association between NINEIN Pro1111Ala (rs2236316), a missense single nucleotide polymorphism, and the risk of colorectal cancer (CRC), related to smoking and alcohol consumption habits in 200 patients with CRC and 1,141 cancer-free control participants were assessed in a case-control study performed in Japan. The results showed that the NINEIN Ala/Ala genotype compared with the Pro/Pro genotype was significantly more associated with an increased risk of CRC, and the males with the Ala/Ala genotype exhibited a significantly increased risk of CRC compared with those with Pro/Pro and Pro/Ala genotypes. Stratified analyses of the Ala/Ala genotype with CRC risk further showed an increased association in never/light drinkers (<23 g of ethanol/day), in male never/light drinkers and in male patients with rectal cancer. These findings suggest that the genetic variant of the NINEIN Pro1111Ala polymorphism has a significant effect on CRC susceptibility in the Japanese population.

Why has Japan become the world's most long-lived country: insights from a food and nutrition perspective

In an international comparison of recent mortality statistics among G7 countries, Japan had the longest average life expectancy, primarily due to remarkably low mortality rates from ischemic heart disease and cancer (particularly breast and prostate). As recently as the 1960s, life expectancy in Japan was the shortest among the G7 countries, owing to relatively high mortality from cerebrovascular disease—particularly intracerebral hemorrhage—and stomach cancer. Mortality rates for these diseases subsequently decreased significantly while the already low rates for ischemic heart disease and cancer also decreased, resulting in Japanese life expectancy becoming the longest. The low mortality rates from ischemic heart disease and cancer are thought to reflect the low prevalence of obesity in Japan; low intake of red meat, specifically saturated fatty acids; and high intakes of fish, specifically n-3 polyunsaturated fatty acids, plant foods such as soybeans, and nonsugar-sweetened beverages such as green tea. The decreasing mortality rates from cerebrovascular disease are thought to reflect the increases in animal foods, milk, and dairy products and consequently in saturated fatty acids and calcium, together with a decrease in salt intake which may have led to a decrease in blood pressure. This decrease in salt and highly salted foods also seems to account for the decrease in stomach cancer. The typical Japanese diet as characterized by plant food and fish as well as modest Westernized diet such as meat, milk and dairy products might be associated with longevity in Japan.

Estimation of lifetime cumulative mortality risk of lung cancer by smoking status in Japan

The main objective of this study was to estimate the cumulative mortality risk for lung cancer according to smoking status and exposure to secondhand smoke (SHS) in Japan. We applied a life-table method to estimate the cumulative risk. Estimated lifetime cumulative risk for 20-year-old non-smokers, former, and current smokers was 3.2%, 7.6%, and 14.9% for men and 1.9%, 5.6%, and 7.2% for women, respectively. For males, the estimated risk was 3.2% for non-smokers not exposed to SHS and 4.1% for non-smokers exposed to SHS. For females, the estimated risk was 1.9% for non-smokers not exposed to SHS and 2.4% for non-smokers exposed to SHS. Lifetime cumulative mortality risk differed greatly according to smoking status. Moreover, SHS exposure resulted in observable differences in lifetime mortality risk. This study may be useful for the development of tailored prevention programs.

Efficacy of immunotherapy targeting the neoantigen derived from epidermal growth factor receptor T790M/C797S mutation in non-small cell lung cancer

Lung cancer is the leading cause of cancer‐related deaths worldwide. Epidermal growth factor receptor‐tyrosine kinase inhibitors (EGFR‐TKI) often have good clinical activity against non–small cell lung cancer (NSCLC) with activating EGFR mutations. Osimertinib, which is a third‐generation EGFR‐TKI, has a clinical effect even on NSCLC harboring the threonine to methionine change at codon 790 of EGFR (EGFR T790M) mutation that causes TKI resistance. However, most NSCLC patients develop acquired resistance to osimertinib within approximately 1 year, and 40% of these patients have the EGFR T790M and cysteine to serine change at codon 797 (C797S) mutations. Therefore, there is an urgent need for the development of novel treatment strategies for NSCLC patients with the EGFR T790M/C797S mutation. In this study, we identified the EGFR T790M/C797S mutation‐derived peptide (790‐799) (MQLMPFGSLL) that binds the human leukocyte antigen (HLA)‐A*02:01, and successfully established EGFR T790M/C797S‐peptide‐specific CTL clones from human PBMC of HLA‐A2 healthy donors. One established CTL clone demonstrated adequate cytotoxicity against T2 cells pulsed with the EGFR T790M/C797S peptide. This CTL clone also had high reactivity against cancer cells that expressed an endogenous EGFR T790M/C797S peptide using an interferon‐γ (IFN‐γ) enzyme‐linked immunospot (ELISPOT) assay. In addition, we demonstrated using a mouse model that EGFR T790M/C797S peptide‐specific CTL were induced by EGFR T790M/C797S peptide vaccine in vivo. These findings suggest that an immunotherapy targeting a neoantigen derived from EGFR T790M/C797S mutation could be a useful novel therapeutic strategy for NSCLC patients with EGFR‐TKI resistance, especially those resistant to osimertinib.

Trends in the Incidence of Stomach Cancer in Golestan Province, a High-risk Area in Northern Iran, 2004-2016

BACKGROUND

We aimed to present the temporal and geographical trends in the incidence of stomach cancer in the Golestan province, a high-risk area in Northern Iran.

METHODS

This study was conducted on stomach cancer cases registered in the Golestan Population-based Cancer Registry (GPCR) during 2004-2016. Age-standardized incidence rates (ASRs) per 100000 person-years were calculated. The Joinpoint regression analysis was used to calculate the average annual percent changes (AAPC). We also calculated the contribution of population aging, population size and risk to the overall changes in incidence rates.

RESULTS

Overall, 2964 stomach cancer patients were registered. The ASR of stomach cancer was significantly higher in men (26.9) than women (12.2) (P<0.01). There was a significant decreasing trend in incidence of stomach cancer in men (AAPC=-1.80, 95% CI: -3.30 to-0.28; P=0.02). We found a higher ASR of stomach cancer in the rural (21.4) than urban (18.1) (P=0.04) population, as well as a significant decreasing trend in its rates (AAPC=-2.14, 95% CI: -3.10to-1.17; P<0.01). The number of new cases of stomach cancer increased by 22.33% (from 215 in 2004 to 263 in 2016), of which 18.1%, 25.1% and -20.9% were due to population size, population aging and risk, respectively. Our findings suggest a higher rate for stomach cancer in eastern areas.

CONCLUSION

We found high incidence rates as well as temporal and geographical diversities in ASR of stomach cancer in Golestan, Iran. Our results showed an increase in the number of new cases, mainly due to population size and aging. Further studies are warranted to determine the risk factors of this cancer in this high-risk population.

HDGF enhances VEGF‑dependent angiogenesis and FGF‑2 is a VEGF‑independent angiogenic factor in non‑small cell lung cancer

Non-small cell lung cancer (NSCLC) accounts for over 80% of all diagnosed lung cancer cases. Lung cancer is the leading cause of cancer-related deaths worldwide. Most NSCLC cells overexpress vascular endothelial growth factor-A (VEGF-A) which plays a pivotal role in tumour angiogenesis. Anti-angiogenic therapies including VEGF-A neutralisation have significantly improved the response rates, progression-free survival and overall survival of patients with NSCLC. However, the median survival of these patients is shorter than 18 months, suggesting that NSCLC cells secrete VEGF-independent angiogenic factors, which remain unknown. We aimed to explore these factors in human NSCLC cell lines, A549, Lu99 and EBC-1 using serum-free culture, to which only EBC-1 cells could adapt. By mass spectrometry, we identified 1,007 proteins in the culture supernatant derived from EBC-1 cells. Among the identified proteins, interleukin-8 (IL-8), macrophage migration inhibitory factor (MIF), galectin-1, midkine (MK), IL-18, galectin-3, VEGF-A, hepatoma-derived growth factor (HDGF), osteopontin (OPN), connective tissue growth factor (CTGF) and granulin (GRN) are known to be involved in angiogenesis. Tube formation, neutralisation and RNA interference assays revealed that VEGF-A and HDGF function as angiogenic factors in EBC-1 cells. To confirm whether VEGF-A and HDGF also regulate angiogenesis in the other NSCLC cell lines, we established a novel culture method. NSCLC cells were embedded in collagen gel and cultured three-dimensionally. Tube formation, neutralisation and RNA interference assays using the three-dimensional (3D) culture supernatant showed that VEGF-A and HDGF were not angiogenic factors in Lu99 cells. By gene microarray in EBC-1 and Lu99 cells, we identified 61 mRNAs expressed only in Lu99 cells. Among these mRNAs, brain-derived neurotrophic factor (BDNF), fibroblast growth factor-2 (FGF-2) and FGF-5 are known to be involved in angiogenesis. Tube formation and neutralisation assays clarified that FGF-2 functions as an angiogenic factor in Lu99 cells. These results indicate that HDGF enhances VEGF-dependent angiogenesis and that FGF-2 is a VEGF-independent angiogenic factor in human NSCLC cells.

Lung cancer occurrence attributable to passive smoking among never smokers in China: a systematic review and meta-analysis

Background

Quantifying the occurrence of lung cancer due to passive smoking is a necessary step when forming public health policy. In this study, we estimated the proportion of lung cancer cases attributable to passive smoking among never smokers in China.

Methods

Six databases were searched up to July 2019 for original observational studies reporting relative risks (RRs) or odds ratios (ORs) for the occurrence of lung cancer associated with passive smoking in Chinese never smokers. The population attributable fraction (PAF) was then calculated using the combined proportion of lung cancer cases exposed to passive smoking and the pooled ORs from meta-analysis. Data are reported with their 95% confidence intervals.

Results

We identified 31 case-control studies of never smokers and no cohort studies. These comprised 9,614 lung cancer cases and 13,093 controls. The overall percentages of lung cancers attributable to passive smoking among never smokers were 15.5% (9.0-21.4%) for 9 population-based studies and 22.7% (16.6-28.3%) for 22 hospital-based studies. The PAFs for women were 17.9% (11.4-24.0%) for the population-based studies and 20.9% (14.7-26.7%) for the hospital-based studies. The PAF for men was only calculable for hospital-based studies, which was 29.0% (95% CI: 8.0-45.2%). Among women, the percentage of lung cancer cases attributable to household exposure (19.5%) was much higher than that due to workplace exposure (7.2%).

Conclusions

We conclude that approximately 16% of lung cancer cases among never smokers in China are potentially attributable to passive smoking. This is slightly higher among women (around 18%), with most cases occurring due to household exposure.

Local and Central Evaluation of HER2 Positivity and Clinical Outcome in Advanced Gastric and Gastroesophageal Cancer-Results from the AGMT GASTRIC-5 Registry

Trastuzumab in combination with a platinum and fluorouracil is the treatment of choice for patients with advanced human epidermal growth factor receptor 2 (HER2) positive gastric cancer and gastroesophageal junction (GEJ) cancer. Pathological assessment of the HER2 status in gastric/GEJ cancer, however, still remains difficult. However, it is a crucial prerequisite for optimal treatment. The GASTRIC-5 registry was designed as an observational, multi-center research initiative comparing local and central HER2 testing. HER2 status was assessed by immunohistochemistry (IHC) and in equivocal cases (IHC score 2+) by additional in-situ hybridization. Between May 2011 and August 2018, tumor samples of 183 patients were tested in local and central pathology laboratories, respectively. Central testing revealed HER2 positivity in 38 samples (21%). Discordant HER2 results were found in 12% (22 out of 183) with locally HER2 positive/centrally HER2 negative results (9%, 17 out of 183), exceeding locally HER2 negative/centrally HER2 positive results (3%, 5 out of 183). Centrally confirmed HER2 positive patients receiving trastuzumab-based palliative first-line therapy showed a longer median overall survival compared to centrally HER2 positive patients not receiving trastuzumab (17.7 months (95% CI: 10,870–24,530) vs. 6.9 months (95% CI: 3.980–9.820), p = 0.016). The findings of the GASTRIC-5 registry corroborate the challenge of HER2 testing in gastric/GEJ cancer and highlight the necessity for central quality control to optimize individual treatment options. Centrally HER2 positive patients not receiving trastuzumab had the worst outcome in a Western real-world gastric/GEJ cancer cohort.

Japanese Legacy Cohorts: Six-Prefecture Cohort Study (Hirayama Cohort Study)

Late Dr Takeshi Hirayama and his colleagues conducted a mortality follow-up of a large-scale cohort in six prefectures in Japan. This study is called the six-prefecture cohort study or Hirayama Cohort Study. The study subjects were residents aged 40 years or older at the baseline survey in 1965, which covered 94.8% of residents identified in the study area by the National Census conducted on October 1, 1965. The mortality of 264,118 cohort members was followed until the end of 1982. One of the most important findings made by this study was an association between second-hand smoke exposure and lung cancer. This finding is the origin of the worldwide spread of smoking ban in indoor public venues and workplaces. Other major findings obtained from the study are also briefly described in this article.

Children's Knowledge of Cancer Prevention and Perceptions of Cancer Patients: Comparison Before and After Cancer Education with the Presence of Visiting Lecturer -Guided Class

The purpose of this study was to investigate the effect of the presence of visiting lecturer-guided class on children's knowledge of cancer prevention and perceptions of cancer patients, conducting surveys before and after the cancer education classes at local elementary schools that are pioneering cancer education. We implemented self-administered questionnaire surveys with 571 sixth-grade children at nine elementary schools receiving cancer education in the Tokyo metropolitan area from September 2013 to February 2014. The surveys were conducted twice in each classroom: 1 week before the cancer education class and 1 week after. The questionnaire items included participants' gender, cancer prevention information, and perceptions of cancer patients with the following description: "looks pitiful," "always depressed," "bedridden and hospitalized," "excessive smoking and drinking," "looks thin and pale," "no visible change despite cancer," and "always bright and cheerful." Children who had not attended the cancer education day, or had not completed both the pre- and post-test, were excluded from the analysis. Regardless of whether there visiting lecturer-guided class was provided, the possibility of improving children's knowledge of cancer prevention was demonstrated. On the other hand, in the post-class surveys, compared to the group with visiting lecturer-guided class, the group without it had a significantly lower percentage of persons selecting "Looks pitiful" (76.2%/63.5%, p = 0.002) and significantly higher percentages for "Too much smoking and drinking," and "Looks thin and pale" (50.2%/63.5%, p = 0.002; 18.8%/31.1%, p = 0.001). Therefore, study is needed into cancer education coordinated with relevant institutions in order to more effectively utilize visiting lecturers and the like.

Prospective study of cancer in Japanese patients with type 2 diabetes: the Fukuoka Diabetes Registry

Background

Although the association between type 2 diabetes and cancer has been reported, few epidemiological studies have been conducted in Japanese patients whose leading cause of death is cancer. We prospectively studied the incidence of site-specific cancer, risk factors for developing cancer, cancer death, and survival in Japanese patients with type 2 diabetes.

Methods

We followed 4923 participants (mean age, 65 years) with type 2 diabetes attending an outpatient diabetes clinic for a median of 5.3 years (follow-up rate, 99.0%).

Results

During the follow-up period, cancer occurred in 450 participants (incidence rate, 22.3/1000 person-years in men and 12.2/1000 person-years in women). In men, prostate cancer was the most common cancer (4.3/1000 person-years), colorectal cancer was the second (3.6/1000 person-years), and gastric cancer was the third (3.3/1000 person-years). In women, colorectal cancer was the most common cancer (2.6/1000 person-years), gastric cancer was the second (2.0/1000 person-years), and breast cancer was the third (1.4/1000 person-years). Smoking, male sex, low-density lipoprotein cholesterol, family history of cancer, and reduced intake of isoflavone daidzein were significant risk factors for developing cancer using multivariable Cox proportional hazards models. The leading cancer death was lung cancer in men and pancreatic cancer in women. The survival was the best for prostate cancer and the worst for pancreatic cancer (2-year cancer-specific survival 95.4%, 30.0%, respectively).

Conclusions

Since the leading cause of death in patients with type 2 diabetes is cancer in Japan, clinicians should be aware of epidemiological data regarding cancer besides diabetic complications.

Radiation and Risk of Liver, Biliary Tract, and Pancreatic Cancers among Atomic Bomb Survivors in Hiroshima and Nagasaki: 1958-2009

The Life Span Study (LSS) of atomic bomb survivors has consistently demonstrated significant excess radiation-related risks of liver cancer since the first cancer incidence report. Here, we present updated information on radiation risks of liver, biliary tract and pancreatic cancers based on 11 additional years of follow-up since the last report, from 1958 to 2009. The current analyses used improved individual radiation doses and accounted for the effects of alcohol consumption, smoking and body mass index. The study participants included 105,444 LSS participants with known individual radiation dose and no known history of cancer at the start of follow-up. Cases were the first primary incident cancers of the liver (including intrahepatic bile duct), biliary tract (gallbladder and other and unspecified parts of biliary tract) or pancreas identified through linkage with population-based cancer registries in Hiroshima and Nagasaki. Poisson regression methods were used to estimate excess relative risks (ERRs) and excess absolute risks (EARs) associated with DS02R1 doses for liver (liver and biliary tract cancers) or pancreas (pancreatic cancer). We identified 2,016 incident liver cancer cases during the follow-up period. Radiation dose was significantly associated with liver cancer risk (ERR per Gy: 0.53, 95% CI: 0.23 to 0.89; EAR per 10,000 person-year Gy: 5.32, 95% CI: 2.49 to 8.51). There was no evidence for curvature in the radiation dose response (P=0.344). ERRs by age-at-exposure categories were significantly increased among those who were exposed at 0-9, 10-19 and 20-29 years, but not significantly increased after age 30 years, although there was no statistical evidence of heterogeneity in these ERRs (P = 0.378). The radiation ERRs were not affected by adjustment for smoking, alcohol consumption or body mass index. As in previously reported studies, radiation dose was not associated with risk of biliary tract cancer (ERR per Gy: -0.02, 95% CI: -0.25 to 0.30). Radiation dose was associated with a nonsignificant increase in pancreatic cancer risk (ERR per Gy: 0.38, 95% CI: <0 to 0.83). The increased risk was statistically significant among women (ERR per Gy: 0.70, 95% CI: 0.12 to 1.45), but not among men.

Risk of cancer and longest-held occupations in Japanese workers: A multicenter hospital-based case-control study

Objectives

Little is known about the risk of developing various cancers according to occupation and occupational physical activity.

Methods

Using nationwide clinical inpatient data (1984‐2017) in Japan, we undertook a multicentered, matched case‐control study with regard to the risk of developing various cancers according to occupation and using patients admitted with fractures as controls. Using standardized national occupation and industrial classifications, we first identified the longest‐held job for each patient. Using sales workers as the reference group, odds ratios (ORs) and 95% confidence intervals (CIs) were estimated by conditional logistic regression, adjusted for age, admission period, and the admitting hospital, with smoking, alcohol consumption, and lifestyle diseases as covariates. The risk of high and low occupational physical activity was also estimated.

Results

Across all occupations, a reduced risk for all common cancers among males was observed among those occupations associated with high physical activities, such as agriculture. People in these occupations tended to show a lower risk for most cancers, including, for example, prostate cancer (OR 0.58, 95% CI 0.45‐0.75) and lung cancer (OR 0.63, 95% CI 0.51‐0.76). For females, the breast cancer risk was low in women engaged in agriculture (OR 0.58, 95% CI 0.45‐0.75) and in those occupations with high levels of occupational physical activity (OR 0.58, 95% CI 0.52‐0.66).

Conclusions

This study revealed differences in cancer risk among diverse occupations in Japan. Specifically, those occupations associated with high levels of physical activity may be associated with a decreased risk of cancer.

The current and future burden of cancer attributable to modifiable risk factors in Canada: Summary of results

Nearly one in two Canadians are expected to be diagnosed with cancer in their lifetime. However, there are opportunities to reduce the impact of modifiable cancer risk factors through well-informed interventions and policies. Since no comprehensive Canadian estimates have been available previously, we estimated the proportion of cancer diagnosed in 2015 and the future burden in 2042 attributable to lifestyle and environmental factors, and infections. Population-based historical estimates of exposure prevalence and their associated risks for each exposure-cancer site pair were obtained to estimate population attributable risks, assuming the exposures were distributed independently and that the risk estimates were multiplicative. We estimated that between 33 and 37% (up to 70,000 cases) of incident cancer cases among adults aged 30 years and over in 2015 were attributable to preventable risk factors. Similar proportions of cancer cases in males (34%) and females (33%) were attributable to these risk factors. Tobacco smoking and a lack of physical activity were associated with the highest proportions of cancer cases. Cancers with the highest number of preventable cases were lung (20,100), colorectal (9800) and female breast (5300) cancer. If current trends in the prevalence of preventable risk factors continue into the future, we project that by 2042 approximately 102,000 incident cancer cases are expected to be attributable to these risk factors per year, which would account for roughly one-third of all incident cancers. Through various risk reduction interventions, policies and public health campaigns, an estimated 10,600 to 39,700 cancer cases per year could be prevented by 2042.

Statistical inference for estimating the incidence of cancer at the prefectural level in Japan

Information of prefectural cancer incidence in Japan is an important resource to plan an effective regional cancer control program. In order to obtain accurate prefectural cancer incidence, we have to adjust for both of completeness of regional cancer registries and regional dispersion, simultaneously, Then, we developed a hierarchal Bayes model with a completeness adjustment by using the relation between MI ratio (mortality divided by incidence) and proportion of death certificate notified among incidence. Prefectural cancer incidence is estimated with the 95% credible interval, which suggests that the national MI ratio should be 0.386 if the registry were complete. Because cancer behavior has a variation depending on prefecture, such accurate incidence must contribute to plan and assess regional cancer control program.

Epidemiology and burden of pancreatic cancer

Pancreatic cancer, although infrequent, has a very poor prognosis, making it currently the fourth common causes of cancer mortality in most developed countries including the European Union (EU). Its incidence varies across regions, which suggests that lifestyle factors play an important role in its etiology, although part of the variation could be ascribed to difference in diagnostic and coding practices. Because pancreatic cancer is strongly age-dependent, increasing population longevity and ageing will lead to an increase of the global burden of pancreatic cancer. It was estimated that, by 2040, the total number of cases in the EU will increase by more than 30%. Pancreatic cancer is a multifactorial disease and many risk factors have been identified. Hereditary factors are responsible for less than 10% of the cases while tobacco smoking and excess body weight, the two most important potentially modifiable risk factors, are responsible for 10 to 30% of the cases, affording a unique opportunity for preventing one of our deadliest cancers.

The Association Between Education and Smoking Prevalence, Independent of Occupation: A Nationally Representative Survey in Japan

Background

Higher smoking prevalence in less educated persons and manual workers is well known. This study examines the independent relationship of education and occupation with tobacco use.

Methods

We used anonymized data from a nationwide population survey (30,617 men and 33,934 women). Education was divided into junior high school, high school, or university attainment. Occupation was grouped into upper non-manual, lower non-manual, and manual. Poisson regression models stratified by age and gender were used to estimate adjusted prevalence ratio (PR) and 95% confidence interval (CI) for current smoking.

Results

After adjustment for covariates, education, and occupation, education was significantly related to current smoking in both genders; compared to university graduates, PRs of junior high school graduates aged 20–39, 40–64, and ≥65 were 1.74 (95% CI, 1.53–1.98), 1.50 (95% CI, 1.36–1.65), and 1.28 (95% CI, 1.08–1.50) among men, and 3.54 (95% CI, 2.92–4.30), 2.72 (95% CI, 2.29–3.23), and 1.74 (95% CI, 1.14–2.66) among women, respectively. However, significantly higher smoking prevalence in manual than in upper non-manual was found only in men aged 20–64; compared to upper non-manual, the PRs of manual workers aged 20–39, 40–64, and ≥65 were 1.11 (95% CI, 1.02–1.22), 1.18 (95% CI, 1.10–1.27), and 1.10 (95% CI, 0.89–1.37) among men, and 0.95 (95% CI, 0.75–1.20), 0.92 (95% CI, 0.75–1.12), and 0.46 (95% CI, 0.22–0.95) among women, respectively.

Conclusions

Independent of occupation, educational disparities in smoking existed, regardless of age and gender. Occupation-smoking relationship varied with age and gender. Our study suggests that we should pay attention to social inequality in smoking as well as national smoking prevalence.

Worldwide incidence of hepatocellular carcinoma cases attributable to major risk factors

To facilitate regionally specific liver cancer prevention and control, this study estimates the fraction of hepatocellular carcinoma (HCC) cases attributable to five major liver cancer risk factors by geographic region. Prevalence estimates of major HCC risk factors, including chronic infection with hepatitis B and hepatitis C, alcohol drinking, tobacco smoking, obesity, and diabetes, were extracted for each country from the literature, along with recent incidence and risk estimate data, to calculate regionally specific population attributable fractions. Overall, 44% of HCC cases worldwide were attributable to chronic hepatitis B infection, with the majority of cases occurring in Asia. Hepatitis C was responsible for 21% of cases. Lifestyle risk factors such as alcohol drinking and obesity were responsible for a larger percentage of cases in North America and Western, Central, and Eastern Europe. In addition, strong sex disparities were observed when looking at lifestyle risk factors, particularly tobacco smoking, in Asia and Africa. Prominent risk factors for HCC vary depending on the region. Our findings provide useful data for developing regionally specific guidelines for liver cancer prevention and control worldwide.

The Linear No-Threshold Model of Low-Dose Radiogenic Cancer: A Failed Fiction

The linear no-threshold (LNT) model for low-dose, radiogenic cancer has been a fixture of radiation protection and regulatory requirements for decades, but its validity has long been contested. This article finds, yet again, more questionable data and analyses purporting to support the model, this within the “gold-standard” data set for estimating radiation effects in humans. Herein is addressed a number of significant uncertainties in the Radiation Effects Research Foundation’s Life Span Study (LSS) cohort of atomic bomb survivors, especially in its latest update of 2017, showing that the study’s support of the LNT model is not evidence based. We find that its latest 2 analyses of solid cancer incidence ignore biology and do not support the LNT model. Additionally, we identify data inconsistencies and missing causalities in the LSS data and analyses that place reliance on uncertain, imputed data and apparently flawed modeling, further invalidating the LNT model. These observations lead to a most credible conclusion, one supporting a threshold model for the dose–response relationship between low-dose radiation exposure and radiogenic cancer in humans. Based upon these findings and those cited from others, it becomes apparent that the LNT model cannot be scientifically valid.

Disparities by province, age, and sex in site-specific cancer burden attributable to 23 potentially modifiable risk factors in China: a comparative risk assessment

BACKGROUND

Understanding disparities in the burden of cancer attributable to different risk factors is crucial to inform and improve cancer prevention and control. In this report, we estimate the site-specific population-attributable fractions (PAFs) for 23 potentially modifiable risk factors across all provinces in China.

METHODS

In this comparative risk assessment study, we used 2014 cancer mortality data for adults from 978 county-level surveillance points in 31 provinces of mainland China. Risk-factor prevalence estimates were obtained from representative surveys. We used summary relative risks obtained from several recent large-scale pooled analyses or high-quality meta-analyses of studies in China. We calculated PAFs using multiple formulae incorporating exposure prevalence and relative risk data stratified by age, sex and province and then combined to create summary PAFs by sex, cancer site, and risk factors.

FINDINGS

About 1 036 004 cancer deaths (45·2% of all cancer deaths [95% CI 44·0-46·4]) in China in 2014 in adults aged 20 years or older were attributable to 23 evaluated risk factors. The PAF was higher in men (51·2% [95% CI 50·0-52·4]) than in women (34·9% [33·6-36·2]), with the leading risk factors being active smoking in men and low fruit intake in women. By province, the PAF in both sexes combined ranged from 35·2% in Shanghai to 52·9% in Heilongjiang, while the PAF varied from 40·9% in Shanghai to 56·4% in Guangdong among men and from 26·9% in Shanghai to 48·0% in Heilongjiang among women. The highest PAF among men was smoking in all 31 provinces, whereas among women it varied among low fruit intake (14 provinces), hepatitis B virus infection (seven provinces), smoking (six provinces), excess bodyweight (three provinces), and human papilloma virus infection (one province).

INTERPRETATION

The PAFs of cancers attributable to potentially modifiable risk factors vary substantially across provinces in China. Regional adoption of effective primary cancer prevention strategies has a vast potential to reduce the burden of cancer and disparities in China. Smoking, poor diet, and infection warrant particular policy attention as they contributed a large proportion to the total cancer burden.

FUNDING

National Science and Technology Basic Research Special Foundation of China.

Occupational class and male cancer incidence: Nationwide, multicenter, hospital-based case-control study in Japan

Little is known about socioeconomic inequalities in male cancer incidence in nonwestern settings. Using the nationwide clinical and occupational inpatient data (1984‐2016) in Japan, we performed a multicentered, matched case–control study with 214 123 male cancer cases and 1 026 247 inpatient controls. Based on the standardized national classifications, we grouped patients’ longest‐held occupational class (blue‐collar, service, professional, manager), cross‐classified by industrial cluster (blue‐collar, service, white‐collar). Using blue‐collar workers in blue‐collar industries as the referent group, odds ratios (ORs) and 95% confidence intervals (CIs) were estimated by conditional logistic regression with multiple imputation, matched for age, admission date, and admitting hospital. Smoking and alcohol consumption were additionally adjusted. Across all industries, a reduced risk with higher occupational class (professionals and managers) was observed for stomach and lung cancer. Even after controlling for smoking and alcohol consumption, the reduced odds persisted: OR of managers in white‐collar industries was 0.80 (95% CI 0.72‐0.90) for stomach cancer, and OR of managers in white‐collar industries was 0.66 (95% CI 0.55‐0.79) for lung cancer. In white‐collar industries, higher occupational class men tended to have lower a reduced risk for most common types of cancer, with the exception of professionals who showed an excess risk for prostate cancer. We documented socioeconomic inequalities in male cancer incidence in Japan, which could not be explained by smoking and alcohol consumption.

Preventable fractions of colon and breast cancers by increasing physical activity in Brazil: perspectives from plausible counterfactual scenarios

BACKGROUND

Physical activity is associated with lower risk of colon and breast cancers. Herein we estimated preventable fractions of colon and breast cancers in Brazil by increasing population-wide physical activity to different counterfactual scenarios.

METHODS

We used data from a representative national survey in Brazil and corresponding relative risks of colon and postmenopausal breast cancers from a meta-analysis. Estimated cancer incidence was retrieved from GLOBOCAN and Brazilian National Cancer Institute. Five counterfactual scenarios for physical activity were considered: (i) theoretical minimum risk exposure level (≥8,000 metabolic equivalent of tasks-minute/week - MET-min/week); (ii) physical activity recommendation (≥600 MET-min/week); (iii) a 10% reduction in prevalence of insufficient physical inactivity (<600 MET-min/week); (iv) physical activity level in each state equals the most active state in Brazil; (v) closing the gender differences in physical activity.

RESULTS

About 19% (3,630 cases) of colon cancers and 12% (6,712 cases) of postmenopausal breast cancers could be prevented by increasing physical activity to ≥8,000 MET-min/week. Plausible counterfactual scenarios suggested the following impact on cancer prevention: reaching physical activity recommendation: 1.7% (1,113 cases) of breast and 6% (1,137 cases) of colon; 10% reduction in physical inactivity prevalence: 0.2% (111 cases) of breast and 0.6% (114 cases) of colon; most active state scenario: 0.3% (168 cases) of breast and 1% (189 cases) of colon; reducing gender differences in physical activity: 1.1% (384 cases) of breast and 0.6% (122 cases) of colon.

CONCLUSIONS

High levels of physical activity are required to achieve a sizable impact on breast and colon cancer prevention in Brazil.

Epidemiological science and cancer control

Epidemiological methods are essential for the discovery of cancer risks and prognostic factors as well as for the evaluation of cancer prevention measures. In this review, we discuss epidemiological surveillance procedures for data collection and processing to guide and evaluate the consequences of anticancer efforts for populations, assess the identification of cancer risk factors, examine barriers to cancer screening and recommended rules for early diagnosis programs. Epidemiological studies have shown that hindrances to cancer information assessment are currently encountered in developing countries. Known cancer risk factors include social determinants, lifestyle factors, occupational exposures, infectious agents, and genetic and epigenetic alterations. Challenges remain in studying the effectiveness of cancer screening; screening can have detrimental effects, and few cancers clearly benefit from screening. Currently, epidemiology faces the challenge of dealing with distinct levels of data, including factors related to social status, lifestyle and genetics, to reconstruct the causal traits of cancer. Additionally, translating epidemiological knowledge into cancer control demands more implementation studies in the population.

Cancers Due to Excess Weight, Low Physical Activity, and Unhealthy Diet

BACKGROUND

Excess weight, low physical activity, low intakes of dietary fiber, fruits, and vegetables, and high meat and salt intake increase cancer risk.

METHODS

Numbers and proportions (population-attributable fractions, PAF) of incident cancer cases in Germany in 2018 attributable to these factors were estimated by sex and age groups for ages 35 to 84 years using population projections, national cancer incidence and exposure data, and published risk estimates.

RESULTS

Estimated numbers (percentages) of attributable cancers were 30 567 (7%) for excess weight, 27 081 (6%) for low physical activity, 14 474 (3%) for low dietary fiber intake, 9447 (2%) for low fruit and vegetable consumption, 9454 (2%) and 1687 (0.4%) for processed meat and high red meat consumption, respectively, and 1204 (0.3%) for high salt intake. Excess weight substantially contributed to endometrial, renal, and liver cancer (PAF = 24 to 35%). Low physical activity contributed to endometrial, renal, and lung cancer (PAF = 15 to 19%), and dietary factors mainly contributed to colorectal, breast, and lung cancer (PAF = 9 to 16%).

CONCLUSION

A considerable proportion of cancer cases are attributable to excess weight, physical inactivity, and unhealthy dietary habits. Major prevention efforts are needed to reduce the cancer incidence attributable to these avoidable factors.

Evidence-based cancer prevention recommendations for Japanese

A comprehensive evidence-based cancer prevention recommendation for Japanese was developed. We evaluated the magnitude of the associations of lifestyle factors and infection with cancer through a systematic review of the literature, meta-analysis of published data, and pooled analysis of cohort studies in Japan. Then, we judged the strength of evidence based on the consistency of the associations between exposure and cancer and biological plausibility. Important factors were extracted and summarized as an evidence-based, current cancer prevention recommendation: 'Cancer Prevention Recommendation for Japanese'. The recommendation addresses six important domains related to exposure and cancer, including smoking, alcohol drinking, diet, physical activity, body weight and infection. The next step should focus on the development of effective behavior modification programs and their implementation and dissemination.

How asymptomatic are early cancer patients of five organs based on registry data in Japan

BACKGROUND

One reason for the low cancer screening rate in Japan is that people are not concerned about cancer if they do not have symptoms.

METHODS

The authors retrospectively analyzed 18,405 cancer patients using hospital-based cancer registry data collected between 2007 and 2013 at the 13 hospitals of Shimane Prefecture, Japan. The symptomatic rates of five cancers (stomach, colorectal, lung, breast, and cervix) at each stage and the time of early diagnosis were investigated. The early detection rates of symptomatic and asymptomatic individuals were investigated.

RESULTS

The percentages of symptomatic cases tended to increase with progressive stages. The odds ratio (OR) of stage IV compared with that of stage I was 12.23 for stomach, 7.21 for colorectal, 16.91 for lung, 10.30 for breast, and 51.62 for cervical cancer. The proportions of early symptomatic cases at the time of diagnosis were low. Compared with the percentage of early symptomatic cases of stomach cancer of 25.5%, the percentage of lung cancer was the lowest, at 8.2% (OR 0.26), and the percentage of breast cancer was the highest, at 30.2% (OR 1.26). The percentages of early symptomatic cases of colorectal and cervical cancer were 18.9% (OR 0.68) and 19.9% (OR 0.73), respectively. The early detection rates of the asymptomatic and symptomatic groups were 77.6 and 36.1%, respectively.

CONCLUSION

Cancer registry data indicate that early cancers are asymptomatic, and once symptoms appear, treatment may not be effective. Policy makers should inform people of the necessity of cancer screening before they have symptoms.

A comprehensive approach of the gender bias in occupational cancer epidemiology: A systematic review of lung cancer studies (2003-2014)

BACKGROUND

In occupational epidemiology, a male-centered perspective often predominates. We aimed to describe current research practices in terms of gender consideration at different stages of epidemiological studies.

METHODS

A systematic review of occupational lung cancer publications indexed in PubMed was conducted over the period 2003-2014. Articles were described according to the sex composition of their study sample.

RESULTS

In 243 studies, 7 (3%) were women-only, 101 (41%) were mixed, with a disproportionate men-to-women ratio (P50 = 3.5; P75 = 12.4). A shift was observed from mixed and unspecified source populations to men-only final samples. Our results also suggest implicit generalization of results from men-only studies, a lack of tests of interaction and often unjustified sex-adjustment for mixed studies.

CONCLUSIONS

The lower proportion of women in studies cannot be fully explained by their under-representation in the target populations, since there were large numbers of women among both potentially exposed workers and patients diagnosed with lung cancer.

MicroRNAs in Smoking-Related Carcinogenesis: Biomarkers, Functions, and Therapy

Long-term heavy cigarette smoking is a well-known high-risk factor for carcinogenesis in various organs such as the head and neck, lungs, and urinary bladder. Furthermore, cigarette smoking can systemically accelerate aging, and as the result, promoting carcinogenesis via changing the host microenvironment. Various inflammatory factors, hormones, and chemical mediators induced by smoking mediate carcinoma-related molecules and induce carcinogenesis. MicroRNAs (miRNAs) are a family of short noncoding RNA molecules that bind to mRNAs and inhibit their expression. Cigarette smoke induces the expression of various miRNAs, many of which are known to function in the post-transcriptional silencing of anticancer molecules, thereby leading to smoking-induced carcinogenesis. Analysis of expression profiles of smoking-induced miRNAs can help identify biomarkers for the diagnosis and prognosis of smoking-related cancers and prediction of therapeutic responses, as well as revealing promising therapeutic targets. Here, we introduce the most recent and useful findings of miRNA analyses focused on lung cancer and urinary bladder cancer, which are strongly associated with cigarette smoking, and discuss the utility of miRNAs as clinical biomarkers.

Development of a risk prediction model for lung cancer: The Japan Public Health Center-based Prospective Study

Although the impact of tobacco consumption on the occurrence of lung cancer is well‐established, risk estimation could be improved by risk prediction models that consider various smoking habits, such as quantity, duration, and time since quitting. We constructed a risk prediction model using a population of 59 161 individuals from the Japan Public Health Center (JPHC) Study Cohort II. A parametric survival model was used to assess the impact of age, gender, and smoking‐related factors (cumulative smoking intensity measured in pack‐years, age at initiation, and time since cessation). Ten‐year cumulative probability of lung cancer occurrence estimates were calculated with consideration of the competing risk of death from other causes. Finally, the model was externally validated using 47 501 individuals from JPHC Study Cohort I. A total of 1210 cases of lung cancer occurred during 986 408 person‐years of follow‐up. We found a dose‐dependent effect of tobacco consumption with hazard ratios for current smokers ranging from 3.78 (2.00‐7.16) for cumulative consumption ≤15 pack‐years to 15.80 (9.67‐25.79) for >75 pack‐years. Risk decreased with time since cessation. Ten‐year cumulative probability of lung cancer occurrence estimates ranged from 0.04% to 11.14% in men and 0.07% to 6.55% in women. The model showed good predictive performance regarding discrimination (cross‐validated c‐index = 0.793) and calibration (cross‐validated χ² = 6.60; P‐value = .58). The model still showed good discrimination in the external validation population (c‐index = 0.772). In conclusion, we developed a prediction model to estimate the probability of developing lung cancer based on age, gender, and tobacco consumption. This model appears useful in encouraging high‐risk individuals to quit smoking and undergo increased surveillance.

A Cross-sectional Investigation of Cancer-Screening Intentions, Sources of Information, and Understanding of Cancer in Japanese Adolescents

The purpose of this study was to describe the cancer-screening intention, sources of cancer information, and cancer understanding among Japanese adolescents. A cross-sectional nationwide survey involving a self-administered questionnaire was conducted. Response rates of the target schools were 46.4 % (n = 103) for junior high schools and 55.8 % (n = 116) for high schools. From these, we analyzed the data of 2960 junior high school students (1520 males, 1440 females) and 3703 high school students (1546 males, 2157 females) to examine the association between cancer-screening intention and sources of cancer-related information and understanding. A significant association between cancer-screening intention and sources of cancer information and cancer understanding was observed. The screening intention group identified more sources of cancer information than the no-screening intention group did. Understanding about cancer was reported by a higher proportion of students in the screening intention group compared with the no-screening intention group. Recognition that healthy people must take part in cancer screening was significantly associated with screening intention in both junior high (odds ratio (OR), 1.859; 95 % confidence interval (CI), 1.582-2.185; P < 0.001) and high school (OR, 2.485; 95 % CI, 2.139-2.887; P < 0.001) students. Health education at school was indicated by a high proportion of students as a source of cancer-related information, although the association was not significant. The present survey indicated that those in of our sample who intended to undergo future cancer screening (67.8 %) had more sources of information and understanding regarding cancer. Thus, schools should enrich health education curricula with more information and understanding about cancer to promote cancer-screening intention among Japanese adolescents.

Educational gradients in the use of electronic cigarettes and heat-not-burn tobacco products in Japan

Objectives

In addition to electronic cigarettes (e-cigarettes), tobacco companies have recently begun to sell heat-not-burn tobacco products, Ploom and iQOS in Japan. Previous research has reported an inverse association between combustible cigarette smoking and educational attainment, but little is known about the association for e-cigarettes, especially heat-not-burn tobacco products. Our objective was to analyze the relationship between educational attainment and e-cigarette and heat-not-burn tobacco use.

Setting

An internet survey (randomly sampled research agency panelists) in Japan.

Participants

A total of 7338 respondents aged 18–69 years in 2015 (3632 men and 3706women).

Primary measures

Adjusted odds ratios (ORs) of educational attainment for current smoking (combustible cigarettes), e-cigarette ever-use, and heat-not-burn ever-use were calculated by multivariable logistic regression models using covariates including socio-demographic factors. Stratified analyses according to smoking status (combustible cigarettes) were additionally performed for e-cigarette ever-use and heat-not-burn tobacco product ever-use.

Results

Associations between educational attainment and e-cigarette ever-use or heat-not-burn tobacco ever-use are not straightforward, although these associations are not statistically significant except for one cell. For example, using "graduate school" education as a reference category, adjusted ORs for "high school" were 1.44 (95% confidence interval [CI]: 0.85–2.44) for e-cigarettes ever-use and 0.75 (95% CI:0.19–2.97) for heat-not-burn tobacco product ever-use. Among current smokers, compared with “graduate school” (reference), those with lower educational attainment showed 0.6 to 0.7 ORs for e-cigarette ever-use: e.g.,"4-year university"(OR = 0.54, 95% CI:0.24–1.24) and "high school" (OR = 0.69, 95% CI: 0.30–1.60). Among former smokers, lower education indicated higher ORs for both e-cigarettes and heat-not-burn tobacco ever-use.

Conclusions

This study provides baseline information on educational gradients of e-cigarette and heat-not-burn tobacco products, ever-use. As heat-not-burn tobacco products are increasing their market share in Japan, continuous monitoring of these products will be necessary.

Attributable causes of colorectal cancer in China

BACKGROUND

Colorectal cancer is the 4th common cancer in China. Most colorectal cancers are due to modifiable lifestyle factors, but few studies have provided a systematic evidence-based assessment of the burden of colorectal cancer incidence and mortality attributable to the known risk factors in China.

METHODS

We estimated the population attributable faction (PAF) for each selected risk factor in China, based on the prevalence of exposure around 2000 and relative risks from cohort studies and meta-analyses.

RESULTS

Among 245,000 new cases and 139,000 deaths of colorectal cancer in China in 2012, we found that 115,578 incident cases and 63,102 deaths of colorectal cancer were attributable to smoking, alcohol drinking, overweight and obesity, physical inactivity and dietary factors. Low vegetable intake was the main risk factor for colorectal cancer with a PAF of 17.9%. Physical inactivity was responsible for 8.9% of colorectal cancer incidence and mortality. The remaining factors, including high red and processed meat intake, low fruit intake, alcohol drinking, overweight/obesity and smoking, accounted for 8.6%, 6.4%, 5.4%, 5.3% and 4.9% of colorectal cancer, respectively. Overall, 45.5% of colorectal cancer incidence and mortality were attributable to the joint effects of these seven risk factors.

CONCLUSIONS

Tobacco smoking, alcohol drinking, overweight or obesity, physical inactivity, low vegetable intake, low fruit intake, and high red and processed meat intake were responsible for nearly 46% of colorectal cancer incidence and mortality in China in 2012. Our findings could provide a basis for developing guidelines of colorectal cancer prevention and control in China.

Environmental contributions to gastrointestinal and liver cancer in the Asia-Pacific region

In the Asia-Pacific region, gastric, colorectal, and hepatocellular (liver) cancer show substantial regional variation in incidence consistent with the presence of important environmental factors. For gastric cancer, global incidence is concentrated in Asia with substantially higher rates in East Asia than in South-East Asia and Australia. The differences in incidence rates for gastric cancer in the Asia-Pacific region may be due, in part, to differences in the prevalence of Helicobacter pylori infection and the prevalence of H. pylori virulence factors. Smoking is also correlated with gastric cancer risk and is responsible for the highest population attributable fraction among men in East Asia. Colorectal cancer has increased rapidly in incidence to become the third most common digestive cancer in Asia. According to cohort studies in Asia, smoking, alcohol use, obesity, and physical inactivity increase the risk of colorectal cancer. Unlike West Asia, East Asia and Australia have high incidence rates for colorectal cancer that correlates to a high Human Development Index and a high prevalence of alcohol consumption and obesity. Liver cancer is the second most common digestive cancer in Asia. The high incidence of liver cancer in East Asia and South-East Asia is concordant with the high prevalence of hepatitis B virus and hepatitis C virus infection. Other important risk factors include alcohol use, smoking, and diabetes. The identification of the earlier and other environmental factors (currently under investigation) is central to the development and implementation of effective cancer control programs for the region.

News Coverage of Cancer in Japanese Newspapers: A Content Analysis

Newspapers could provide effective and comprehensive information about cancer to the public. The present study conducted a content analysis of cancer-related articles in Japanese newspapers published in 2011. In total, 5,314 articles were identified and subsequently coded. Coding variables included cancer type, the cancer continuum, and topic of articles mentioning cancer. Approximately half mentioned at least one specific type of cancer, with the focus mostly on lung, leukemia, and breast. Stomach and colon cancers, which have the highest morbidity, were relatively underreported. The continuum received little attention, and was mentioned in only 11% of articles. Treatment was the most frequently mentioned part of the continuum, with prevention and screening mentioned only rarely. The most frequently mentioned topic was social issues. The findings suggest that cancer-related articles were found regularly throughout the year, meaning that they might be one of the most important sources of cancer information. However, they are affected by social issues and there were some imbalances in both cancer type and continuum. Considering the influence of newspapers, it would be helpful for providing more effective and accurate information to the public if Japanese newspapers increased mentions of specific types of common cancers and the cancer continuum, especially prevention.