Dietary intake of fruit and vegetable and lung cancer risk: a case–control study in Harbin, northeast China

Secondary Primary Cancer after Primary Gastric Cancer: Literature Review and Big Data Analysis Using the Health Insurance Review and Assessment Service (HIRA) Database of Republic of Korea

Advances in cancer screening and early detection, as well as improvements in surgical techniques and therapeutics, have contributed to decreasing gastric cancer mortality. The number of gastric cancer survivors continues to rise; however, long-term follow-up has revealed an increase in the risk of post-gastrectomy symptoms or other health problems, such as extra-gastric secondary primary cancer (SPC), in these survivors. Therefore, evidence-based screening for new primary cancer is needed in these populations; however, the incidence of SPC varies by country or continent and its characteristics have not been clearly reported. The characteristics of SPC are of increasing interest to both treatment providers and gastric cancer survivors; thus, this literature review explores not only the epidemiology and biology of SPC but also clinical and biological factors that influence its prognosis.

Association between aspirin use and lung cancer incidence depends on high-frequency use, bodyweight, and age in U.S. adults

Background

Chemoprevention of cancer with aspirin is controversial as a primary prevention strategy. We sought to investigate the association between aspirin frequency and risk of lung cancer in The Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial.

Methods

Using data from 101,722 participants in PLCO, we used a Cox regression model coupling with propensity score to detect the association between aspirin frequency and lung cancer risk.

Results

High-frequency aspirin use significantly increased risk of lung cancer by 28% compared to no use (HR =1.28; 95% CI, 1.14–1.45; P=3.37×10⁻⁵), especially for current smoker (HR =1.30; 95% CI, 1.07–1.57; P=6.82×10⁻³). However, the increased lung cancer risk due to high-frequency aspirin use significantly decreased with increasing bodyweight (HR_interaction =0.96; 95% CI, 0.94–0.99; P=1.26×10⁻²). Further, for participants with bodyweight <80 kg, high-frequency aspirin use showed an elevated risk at <76 years of age (HR_age<76 =1.47; 95% CI, 1.25–1.73; P=3.81×10⁻⁶). Our study used propensity score under various confounding and stratification analyses by cardio-cerebrovascular status, which all presented similar evidences.

Conclusions

High-frequency aspirin use is associated with the increased risk of lung cancer. Current smoker or people with age <76 years and bodyweight <80 kg should be more cautious to high-frequency aspirin use for lung cancer chemoprevention. This study provides a new insight for lung cancer chemoprevention.

Is carrot consumption associated with a decreased risk of lung cancer? A meta-analysis of observational studies

Findings of epidemiological studies regarding the association between carrot consumption and lung cancer risk remain inconsistent. The present study aimed to summarise the current epidemiological evidence concerning carrot intake and lung cancer risk with a meta-analysis. We conducted a meta-analysis of case-control and prospective cohort studies, and searched PubMed and Embase databases from their inception to April 2018 without restriction by language. We also reviewed reference lists from included articles. Prospective cohort or case-control studies reporting OR or relative risk with the corresponding 95 % CI of the risk lung cancer for the highest compared with the lowest category of carrot intake. A total of eighteen eligible studies (seventeen case-control studies and one prospective cohort study) were included, involving 202 969 individuals and 5517 patients with lung cancer. The pooled OR of eighteen studies for lung cancer was 0·58 (95 % CI 0·45, 0·74) by comparing the highest category with the lowest category of carrot consumption. Based on subgroup analyses for the types of lung cancer, we pooled that squamous cell carcinoma (OR 0·52, 95 % CI 0·19, 1·45), small-cell carcinoma (OR 0·43, 95 % CI 0·12, 1·59), adenocarcinoma (OR 0·34, 95 % CI 0·15, 0·79), large-cell carcinoma (OR 0·40, 95 % CI 0·10, 1·57), squamous and small-cell carcinoma (OR 0·85, 95 % CI 0·45, 1·62), adenocarcinoma and large-cell carcinoma (OR 0·20, 95 % CI 0·02, 1·70) and mixed types (OR 0·61, 95 % CI 0·46, 0·81). Exclusion of any single study did not materially alter the pooled OR. Integrated epidemiological evidence from observational studies supported the hypothesis that carrot consumption may decrease the risk of lung cancer, especially for adenocarcinoma.

The Role of Cruciferous Vegetables and Isothiocyanates for Lung Cancer Prevention: Current Status, Challenges, and Future Research Directions

Lung cancer remains a leading cause of cancer-related deaths in the United States. Although smoking and air pollution exposure are primary risk factors of lung cancer, diet has also been reported to contribute to lung cancer risk. Cruciferous vegetables contain many bioactive compounds that alter the detoxification process of air-borne carcinogenic compounds and, thereby, may decrease lung cancer risk. In the meta-analysis of 31 observational studies, cruciferous vegetable intake is inversely associated with lung cancer risk (summary odds ratio/relative risk = 0.81 and 95% confidence interval = 0.74-0.89 for comparing the highest with lowest intake categories). More observational studies need to measure urinary isothiocyanate (ITC) concentrations and investigate their association with lung cancer risk in populations with relatively high intake of cruciferous vegetables. Current evidence is limited to two phase 2 clinical trials with incomplete reporting. Hence, more short-term clinical phase 2 trials need to examine effects of various amounts and types of cruciferous vegetables on biomarkers of risk and efficacy before a large phase 3 trial can be conducted to assess effects upon lung cancer risk. This would help further elucidate whether the inverse association observed with self-reported cruciferous vegetable intake is indeed due to ITC content or other bioactive compounds.

Sleep duration and risk of lung cancer in the physicians' health study

Background and Objectives

Lung cancer is the most common cancer and cancer related cause of death worldwide. However, the association between sleep duration and incident lung cancer has not been investigated in a prospective cohort study.

Methods

We prospectively examined the association between sleep duration and incident lung cancer in a cohort of 21, 026 United States (US) male physicians. Self-reported sleep duration was ascertained during 2002 annual follow-up questionnaire. Incident lung cancer was ascertained through yearly follow-up questionnaires. Cox regression was used to estimate relative risk of incident lung cancer.

Results

The average age at baseline was 68.3±8.8 yr. During a mean follow up of 7.5 (±2.2) yr, 150 cases of lung cancer occurred. Using 7 h of sleep as the reference group, multivariable adjusted hazard ratios (95%CI) for lung cancer were 1.18 (0.77-1.82), 1.0 (ref), and 0.97 (0.67-1.41) from lowest to the highest category of sleep duration (P for quadratic trend 0.697), respectively. In a secondary analysis, smoking status did not modify the sleep duration-lung cancer association (P=0.78). Tere was no evidence for an interaction between sleep duration and sleep apnea on the risk of lung cancer either (P=0.65).

Conclusions

Our data failed to show a higher risk of lung cancer in association with altered sleep duration among US male physicians.

The effect of fruit and vegetable intake on the development of lung cancer: a meta-analysis of 32 publications and 20,414 cases

BACKGROUND/OBJECTIVES

Quantification of the association between the intake of vegetables and fruits and the risk of lung cancer is controversial. Thus, we conducted a meta-analysis to assess the relationship between vegetables and fruits and lung cancer risk.

SUBJECTS/METHODS

Pertinent studies were identified by a search in PubMed and Web of Knowledge. Random-effects models were used to calculate summary relative risks (RR) and the corresponding 95% confidence intervals (CI). Publication bias was estimated using Begg's test.

RESULTS

Finally, 30 articles with 37 studies comprising of 20,075 lung cancer cases for vegetables intake with lung cancer risk and 31 articles with 38 studies comprising of 20,213 lung cancer cases for fruits intake with lung cancer risk were included in this meta-analysis. The combined results showed that there were significant associations between vegetables and fruits intake and lung cancer risk. The pooled RR were 0.74 (95% CI: 0.67, 0.82) for vegetables and 0.80 (95% CI: 0.74, 0.88) for fruits. Significant association was found in females on vegetables intake and lung cancer but not in males. The association was also stronger in females than males on fruits intake and lung cancer risk. No publication bias was detected.

CONCLUSIONS

Our analysis indicated that intake of vegetables and fruits may have a protective effect on lung cancer, and the associations were stronger in females. As the potential biases and confounders could not be ruled out completely in this meta-analysis, further studies are needed.

Nutrition and lung cancer: a case control study in Iran

BACKGROUND

Despite many prospective and retrospective studies about the association of dietary habit and lung cancer, the topic still remains controversial. So, this study aims to investigate the association of lung cancer with dietary factors.

METHOD

In this study 242 lung cancer patients and their 484 matched controls on age, sex, and place of residence were enrolled between October 2002 to 2005. Trained physicians interviewed all participants with standardized questionnaires. The middle and upper third consumer groups were compared to the lower third according to the distribution in controls unless the linear trend was significant across exposure groups.

RESULT

Conditional logistic regression was used to evaluate the association with lung cancer. In a multivariate analysis fruit (Ptrend < 0.0001), vegetable (P = 0.001) and sunflower oil (P = 0.006) remained as protective factors and rice (P = 0.008), bread (Ptrend = 0.04), liver (P = 0.004), butter (Ptrend = 0.04), white cheese (Ptrend < 0.0001), beef (Ptrend = 0.005), vegetable ghee (P < 0.0001) and, animal ghee (P = 0.015) remained as risk factors of lung cancer. Generally, we found positive trend between consumption of beef (P = 0.002), bread (P < 0.0001), and dairy products (P < 0.0001) with lung cancer. In contrast, only fruits were inversely related to lung cancer (P < 0.0001).

CONCLUSION

It seems that vegetables, fruits, and sunflower oil could be protective factors and bread, rice, beef, liver, dairy products, vegetable ghee, and animal ghee found to be possible risk factors for the development of lung cancer in Iran.

Fruit and vegetable consumption and lung cancer risk: a case-control study in Galicia, Spain

Lung cancer has multiple risk factors and tobacco is the main one. Diet plays a role, but no clear effect has been consistently observed for different fruit and vegetable consumption. We aim to assess the association between fruit and vegetable consumption and lung cancer risk through a hospital-based case-control study in Spanish population. We recruited incident lung cancer cases in 2 Spanish hospitals from 2004 to 2008. Controls were individuals attending hospital for trivial surgery. Cases and controls were older than 30 and did not have a neoplasic history. We collected information on lifestyle with special emphases on tobacco and dietary habits. We included 371 cases and 496 controls. We found no protective effect for overall fruit consumption. For green leafy vegetables, the odds ratio (OR) was 0.92 [95% confidence interval (CI) = 0.32-2.69), and for other vegetables the OR was 0.77 (95% CI = 0.40-1.48) for the categories compared. We observed a reduced risk for broccoli and pumpkin intake. Although fruit consumption does not seem to be associated with a lower lung cancer risk, only the frequent consumption of specific green leafy vegetables and other vegetables might be associated with a reduced risk of lung cancer.

Gastric cancer and allium vegetable intake: a critical review of the experimental and epidemiologic evidence

There are suggestions of an anticancerogenic effect of allium vegetables and their associated organosulfur components against several cancer types, including gastric cancer, but the issue remains open to discussion and quantification. The present critical review discussed the history, the health properties, the chemistry, the anticancerogenic evidences from experimental studies, and the anticancer mechanisms of allium vegetables. We also summarized findings from epidemiological studies concerning the association between different types of allium vegetables and gastric cancer risk, published up to date. Available data, derived mainly from case-control studies, suggested a favorable role of high intakes of allium vegetables, mainly garlic and onion, in the etiology of gastric cancer. In particular, of 10 studies, 7 suggested a favorable role of high intake of total allium vegetables and gastric cancer. All 14 studies on garlic and most studies on onion (more than 80%) reported a beneficial role of these allium types against gastric cancer. However several limitations, including possible publication bias and the difficulty to establish a dose-risk relationship, suggest caution in the interpretation. Evidences on other types of allium vegetables, as well as on the influence of different gastric cancer anatomical and histological types, are less consistent.

Dietary carrot consumption and the risk of prostate cancer

PURPOSE

Previous studies regarding the association between carrot intake and prostate cancer risk have reported inconsistent results. We conducted a meta-analysis to summarize evidence on this association and to quantify the potential dose-response relationship.

METHOD

A systematic literature search of papers published in August 2013 was conducted using PubMed, EMBASE, Scopus, Web of Science, the Cochrane register, and the Chinese National Knowledge Infrastructure databases, and the references of the retrieved articles were screened. The summary risk estimates with 95% confidence intervals (CIs) for the highest versus the lowest intake of carrots were calculated. A dose-response meta-analysis was also conducted for the studies reporting categorical risk estimates for a series of exposure levels.

RESULTS

We found a significantly decreased risk of prostate cancer associated with the intake of carrots (odds ratio 0.82, 95% CI 0.70-0.97). In addition, the dose-response meta-analysis indicated that for each serving per week, or 10 g per day increment of carrot intake, the risk estimate of prostate cancer was 0.95 (0.90-0.99) or 0.96 (0.94-0.99). There was no evidence of significant publication bias based on Begg's funnel plot (P = 1.000) or Egger's test (P = 0.804).

CONCLUSION

Carrot intake might be inversely associated with prostate cancer risk. Because of the limited number of cohort studies and substantial heterogeneity observed between studies in this meta-analysis, further well-designed prospective studies are warranted to confirm the findings from our study.

Lung cancer correlates in Lebanese adults: a pilot case--control study

BACKGROUND

Lung cancer is one of the most prevalent types of cancers. However, there are no epidemiological studies concerning lung cancer and its risk factors in Lebanon. This study was carried out to determine the association between lung cancer and its most common risk factors in a sample of the Lebanese population.

METHODS

A hospital-based case-control study was conducted. Patients were recruited in a tertiary health care center. A questionnaire in Arabic was designed to assess the possible risk factors for lung cancer.

RESULTS

For females, cigarette smoking (ORa=9.76) and using fuel for heating (ORa=9.12) were found to be the main risk factors for lung cancer; for males, cigarette smoking (ORa=156.98), living near an electricity generator (ORa=13.26), consuming low quantities of fruits and vegetables (ORa=10.54) and a family history of cancer (ORa=8.75) were associated with lung cancer. Waterpipe smoking was significantly correlated with lung cancer in the bivariate analysis.

CONCLUSION

In this pilot study, it was found that in addition to smoking, outdoor and indoor pollution factors were potential risk factors of lung cancer. Additional studies would be necessary to confirm these findings.

Ginger phytochemicals exhibit synergy to inhibit prostate cancer cell proliferation

Dietary phytochemicals offer nontoxic therapeutic management as well as chemopreventive intervention for slow-growing prostate cancers. However, the limited success of several single-agent clinical trials suggest a paradigm shift that the health benefits of fruits and vegetables are not ascribable to individual phytochemicals, rather may be ascribed to synergistic interactions among them. We recently reported growth-inhibiting and apoptosis-inducing properties of ginger extract (GE) in in vitro and in vivo prostate cancer models. Nevertheless, the nature of interactions among the constituent ginger biophenolics, viz. 6-gingerol, 8-gingerol, 10-gingerol, and 6-shogoal, remains elusive. Here we show antiproliferative efficacy of the most-active GE biophenolics as single-agents and in binary combinations, and investigate the nature of their interactions using the Chou-Talalay combination index (CI) method. Our data demonstrate that binary combinations of ginger phytochemicals synergistically inhibit proliferation of PC-3 cells with CI values ranging from 0.03 to 0.88. To appreciate synergy among phytochemicals present in GE, the natural abundance of ginger biophenolics was quantitated using LC-UV/MS. Interestingly, combining GE with its constituents (in particular, 6-gingerol) resulted in significant augmentation of GE's antiproliferative activity. These data generate compelling grounds for further preclinical evaluation of GE alone and in combination with individual ginger biophenols for prostate cancer management.

Dietary patterns affect lung cancer risk in never smokers

A number of studies suggest a role of dietary factors as risk predictors of lung cancer in never smokers. However, it is difficult to interpret the observed associations of lung cancer risk with any particular dietary item due to high correlation among different dietary items. In this study, we derived uncorrelated patterns of dietary items in the never smokers and evaluated the association of these patterns with lung cancer risk, using food frequency data from 299 never-smoker lung cancer patients and 317 controls enrolled in an ongoing case-control lung cancer study. We identified 2 major dietary patterns in never smokers: a "healthy eating" pattern including vegetables, fruits, and low-fat food items, and a "mixed dishes" pattern including most foods with positive loadings. Using multivariable regression analysis, we show that the healthy eating pattern is associated with a significant reduction of lung cancer risk among never smokers. The effect of the healthy eating pattern remained significant after adjustment for age, gender, education, caloric intake, secondhand smoke exposure, and family history of cancer. This finding, if confirmed in a prospective study, has a clear preventive significance, by promoting interventions encouraging healthier diets.

Nutrition aspects of lung cancer

Lung cancer is the most common type of cancer, excluding nonmelanoma skin cancer, and is the leading cause of cancer death in the United States. Notable carcinogens involved in the development of lung cancer include smoking, secondhand smoke, and radon. Lung cancer is divided into 2 major types: non-small-cell lung cancer, the most prevalent, and small-cell lung cancer. Treatment includes surgery, chemotherapy, radiation, or a combination of the same. Medical nutrition therapy is often required for nutrition-related side effects of cancer treatment, which include but are not limited to anorexia, nausea and vomiting, and esophagitis. The best protection against lung cancer is avoidance of airborne carcinogens and increased consumption of fruits and vegetables. Studies have shown that smokers taking large amounts of beta-carotene and vitamin A supplements had increased lung cancer incidence and mortality. However, ingestion of beta-carotene from foods, along with a diet rich in fruits and vegetables, has a protective role against lung disease. The use of complementary and alternative medicine by lung cancer patients is prevalent; therefore, clinicians should investigate whether complementary and alternative therapies are used by patients and advise them on the use of these therapies to avoid any potential side effects and interactions with conventional therapies. The article concludes with a case study of a patient with non-small-cell lung cancer and illustrates the use of medical nutrition therapy in relation to cancer treatment side effects.

Is temperature an effect modifier of the association between green tea intake and gastric cancer risk?

We considered the relationship between green tea and gastric cancer risk in Harbin, Heilongjiang province, Northeast China, an area with high baseline risk of stomach cancer. We used data from a case-control study conducted from 1987 to 1989 among 266 incident cases of stomach cancer and 533 controls admitted to the same hospitals as cases, with non-neoplastic and non-gastric diseases. No association emerged when tea consumption alone was considered: the odds ratio (OR) for green tea consumption was 0.87 (95% CI: 0.60-1.25) for green tea intake > or = 750 g/year versus no intake and 0.99 (95% CI: 0.97-1.02) for an increment of 500 g of tea per year. When tea consumption was classified according to the temperature, however, the OR was 0.19 (95% CI: 0.07-0.49) for lukewarm tea intake > or = 750 g/year and 1.27 (95% CI: 0.85-1.90) for hot tea intake (P value for interaction <0.001) as compared with non-drinkers. The corresponding ORs for an increment of 500 g of tea per year were 0.61 (95% CI: 0.45-0.82) and 1.03 (95% CI: 0.99-1.07) for lukewarm and hot tea, respectively (P value for interaction <0.001). We found an inverse relationship between green tea drinking and gastric cancer risk limited to the intake of lukewarm tea.

Lung cancer in never smokers: clinical epidemiology and environmental risk factors

More than 161,000 lung cancer deaths are projected to occur in the United States in 2008. Of these, an estimated 10 to 15% will be caused by factors other than active smoking, corresponding to 16,000 to 24,000 deaths annually. Thus lung cancer in never smokers would rank among the most common causes of cancer mortality in the United States if considered as a separate category. Slightly more than half of the lung cancers caused by factors other than active smoking occur in never smokers. As summarized in the accompanying article, lung cancers that occur in never smokers differ from those that occur in smokers in their molecular profile and response to targeted therapy. These recent laboratory and clinical observations highlight the importance of defining the genetic and environmental factors responsible for the development of lung cancer in never smokers. This article summarizes available data on the clinical epidemiology of lung cancer in never smokers, and several environmental risk factors that population-based research has implicated in the etiology of these cancers. Primary factors closely tied to lung cancer in never smokers include exposure to known and suspected carcinogens including radon, second-hand tobacco smoke, and other indoor air pollutants. Several other exposures have been implicated. However, a large fraction of lung cancers occurring in never smokers cannot be definitively associated with established environmental risk factors, highlighting the need for additional epidemiologic research in this area.

Cruciferous vegetable consumption and lung cancer risk: a systematic review

BACKGROUND

Cruciferous vegetables, rich in isothiocyanates, may protect against lung cancer. Glutathione S-transferases are important in metabolizing isothiocyanates; hence, variants in GST genes may modify the association between cruciferous vegetable intake and lung cancer. We carried out a systematic review to characterize the association between cruciferous vegetable intake and lung cancer risk, with an emphasis on the potential interaction between cruciferous vegetables and GSTM1 and GSTT1 gene variants.

METHODS

A search of the epidemiologic literature through December 2007 was conducted using 15 bibliographic databases without language restrictions. Thirty studies on the association between lung cancer and either total cruciferous vegetable consumption (6 cohort and 12 case-control studies) or specific cruciferous vegetables (1 cohort and 11 case-control studies) were included.

RESULTS

The risk for lung cancer among those in the highest category of total cruciferous vegetable intake was 22% lower in case-control studies [random-effects pooled odds ratio, 0.78; 95% confidence interval (95% CI), 0.70-0.88] and 17% lower in cohort studies (pooled relative risk, 0.83; 95% CI, 0.62-1.08) compared with those in the lowest category of intake. The strongest inverse association of total cruciferous vegetable intake with lung cancer risk was seen among individuals with GSTM1 and GSTT1 double null genotypes (odds ratio, 0.41; 95% CI, 0.26-0.65; P for interaction = 0.01).

CONCLUSIONS

Epidemiologic evidence suggests that cruciferous vegetable intake may be weakly and inversely associated with lung cancer risk. Because of a gene-diet interaction, the strongest inverse association was among those with homozygous deletion for GSTM1 and GSTT1.

Consumption of fruit and vegetables and risk of lung cancer: a case-control study in Galicia, Spain

OBJECTIVE

We analyzed the effect of fruit and vegetable intake on lung cancer risk in a population in northwest Spain.

METHODS

We analyzed data from a hospital-based case-control study including 295 histologically confirmed cases and 322 controls. Controls were patients attending the hospital for minor surgery. There was a minimum age limit of 35 y and sampling was carried out on a sex-frequency basis.

RESULTS

After adjustment for sex, age, tobacco use, and occupation, no protective effect of overall consumption of fruit was present (odds ratio 1.49, 95% confidence interval 0.81-2.73). Green leafy vegetables conferred a protective effect (odds ratio 0.50, 95% confidence interval 0.30-0.83).

CONCLUSION

These findings indicate that green leafy vegetables, rather than fruit, might have a genuine protective effect against lung cancer.

Dietary factors, food contamination and lung cancer risk in Xuanwei, China

BACKGROUND

In rural Xuanwei County, China, the high incidence of lung cancer is attributable largely to burning smoky coal indoors for heating and cooking without adequate ventilation. Such burning generates very high levels of indoor air pollutants, including carcinogenic polycyclic aromatic hydrocarbons, which could contaminate foodstuffs in the home. Thus, residents could be exposed to carcinogenic coal emissions not only via inhalation but also via ingestion of these foodstuffs.

METHODS

A population-based case-control study of 498 lung cancer patients and 498 controls was conducted from 1985 through 1990 in Xuanwei. The interviewer-administered study questionnaire queried the frequency of food items commonly consumed in this region. Overall and sex-specific multiple logistic regression models were constructed to estimate Odds ratios (OR) and 95% confidence intervals (CI) for consumption of these foods.

RESULTS

Intake of rice, green vegetables, mushrooms and fresh meat was associated with an increased risk of lung cancer. In contrast, intake of corn, buckwheat, radishes, peppers, melons, pickled vegetables, and salt-preserved meats was associated with reduced risk. The detrimental effect of ingesting green vegetables (OR, 2.39; 95% CI, 1.28-4.48) is consistent with previous reports.

CONCLUSIONS

These findings suggest that in Xuanwei, food contamination by environmental polycyclic aromatic hydrocarbons may be an important risk factor for lung cancer, and that differential contamination of foods by polycyclic aromatic hydrocarbons possibly explained the different associations with lung cancer risk.