Cigarette smoking and risk of prostate cancer among Singapore Chinese

Risk of urinary tract cancers following arsenic exposure and tobacco smoking: a review

Bladder cancer, prostate cancer, and kidney cancer, due to their high morbidity and mortality rates, result in significant economic and health care costs. Arsenic exposure affects the drinking water of millions of people worldwide. Long-term exposure to arsenic, even in low concentrations, increases the risk of developing various cancers. Smoking is also one of the leading causes of bladder, prostate and kidney cancers. Accordingly, this research reviews the relationship between arsenic exposure and smoking with three kinds of urinary tract cancers (bladder cancer, prostate cancer, and kidney cancer) due to their widespread concern for their negative impact on public health globally. In this review, we have gathered the most current information from scientific databases [PubMed, Scopus, Google Scholar, ISI web of science] regarding the relationship between arsenic exposure and tobacco smoking with the risk of bladder, prostate, and kidney cancer. In several studies, a significant relationship was determined between the incidence and mortality rate of the above-mentioned cancers in humans with arsenic exposure and tobacco smoking. The decrease or cessation of smoking and consumption of arsenic-free water significantly declined the incidence of bladder, prostate, and kidney cancers.

Association of cigarette smoking habits with the risk of prostate cancer: a systematic review and meta-analysis

BACKGROUND

Association of cigarette smoking habits with the risk of prostate cancer is still a matter of debate. This systematic review and meta-analysis aimed to assess the association between cigarette smoking and prostate cancer risk.

METHODS

We conducted a systematic search on PubMed, Embase, Cochrane Library, and Web of Science without language or time restrictions on June 11, 2022. Literature search and study screening were performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. Prospective cohort studies that assessed the association between cigarette smoking habits and the risk of prostate cancer were included. Quality assessment was conducted using the Newcastle-Ottawa Scale. We used random-effects models to obtain pooled estimates and the corresponding 95% confidence intervals.

RESULTS

A total of 7296 publications were screened, of which 44 cohort studies were identified for qualitative analysis; 39 articles comprising 3 296 398 participants and 130 924 cases were selected for further meta-analysis. Current smoking had a significantly reduced risk of prostate cancer (RR, 0.74; 95% CI, 0.68-0.80; P < 0.001), especially in studies completed in the prostate-specific antigen screening era. Compared to former smokers, current smokers had a significant lower risk of PCa (RR, 0.70; 95% CI, 0.65-0.75; P < 0.001). Ever smoking showed no association with prostate cancer risk in overall analyses (RR, 0.96; 95% CI, 0.93-1.00; P = 0.074), but an increased risk of prostate cancer in the pre-prostate-specific antigen screening era (RR, 1.05; 95% CI, 1.00-1.10; P = 0.046) and a lower risk of prostate cancer in the prostate-specific antigen screening era (RR, 0.95; 95% CI, 0.91-0.99; P = 0.011) were observed. Former smoking did not show any association with the risk of prostate cancer.

CONCLUSIONS

The findings suggest that the lower risk of prostate cancer in smokers can probably be attributed to their poor adherence to cancer screening and the occurrence of deadly smoking-related diseases, and we should take measures to help smokers to be more compliant with early cancer screening and to quit smoking.

TRIAL REGISTRATION

This study was registered on PROSPERO (CRD42022326464).

Cigarette smoking and prostate cancer: A systematic review and meta-analysis of prospective cohort studies

INTRODUCTION

Cigarette smoking is a well-known cancer-causing behavior and a leading cause of death from cancer. However, according to previously published research and meta-analyses, cigarette smoking has a significant inverse association with prostate cancer incidence. Therefore, this study aims to investigate this association based on updated evidence by conducting a systematic review and meta-analysis.

METHODS

A search for relevant articles was performed in PubMed and Scopus databases to obtain the pooled relative risk (RR) and the corresponding 95% confidence intervals (CIs) for the risk of prostate cancer incidence among smokers compared to non-smokers. Our search was limited to prospective cohort studies.

RESULTS

A total of 17 cohort studies were included in the systematic review. Fifteen studies were included in the meta-analysis and showed that cigarette smoking has an inverse association with prostate cancer incidence with a relative risk of 0.84 (95% CI: 0.78-0.91). From all cohorts included in this systematic review, five studies examined the association between current smokers and the risk of death from prostate cancer. Therefore, a meta-analysis of these cohort studies was performed and showed that current smokers had a 42% higher risk of death from prostate cancer when compared to non-smokers with a relative risk of 1.42 (95% CI: 1.20-1.68).

CONCLUSIONS

Data from observational studies suggest that cigarette smoking has an inverse association with prostate cancer incidence. However, smokers have an increased risk of death from prostate cancer. Important to realize that this lower risk for smokers might be attributed to low prostate cancer screening uptake among smokers, misclassification bias, or selection bias from the included original studies. In summary, our results indicate that the incidence of prostate cancer is lower among smokers. Nevertheless, smokers who develop the disease have a significantly worse prognosis.

Health effects associated with smoking: a Burden of Proof study

As a leading behavioral risk factor for numerous health outcomes, smoking is a major ongoing public health challenge. Although evidence on the health effects of smoking has been widely reported, few attempts have evaluated the dose-response relationship between smoking and a diverse range of health outcomes systematically and comprehensively. In the present study, we re-estimated the dose-response relationships between current smoking and 36 health outcomes by conducting systematic reviews up to 31 May 2022, employing a meta-analytic method that incorporates between-study heterogeneity into estimates of uncertainty. Among the 36 selected outcomes, 8 had strong-to-very-strong evidence of an association with smoking, 21 had weak-to-moderate evidence of association and 7 had no evidence of association. By overcoming many of the limitations of traditional meta-analyses, our approach provides comprehensive, up-to-date and easy-to-use estimates of the evidence on the health effects of smoking. These estimates provide important information for tobacco control advocates, policy makers, researchers, physicians, smokers and the public.

The Impact of Lifestyle on Prostate Cancer: A Road to the Discovery of New Biomarkers

Prostate cancer (PCa) is one of the most common cancers among men, and its incidence has been rising through the years. Several risk factors have been associated with this disease and unhealthy lifestyles and inflammation were appointed as major contributors for PCa development, progression, and severity. Despite the advantages associated with the currently used diagnostic tools [prostate-specific antigen(PSA) serum levels and digital rectal examination (DRE)], the development of effective approaches for PCa diagnosis is still necessary. Finding lifestyle-associated proteins that may predict the development of PCa seems to be a promising strategy to improve PCa diagnosis. In this context, several biomarkers have been identified, including circulating biomarkers (CRP, insulin, C-peptide, TNFα-R2, adiponectin, IL-6, total PSA, free PSA, and p2PSA), urine biomarkers (PCA3, guanidine, phenylacetylglycine, and glycine), proteins expressed in exosomes (afamin, vitamin D-binding protein, and filamin A), and miRNAs expressed in prostate tissue (miRNA-21, miRNA-101, and miRNA-182). In conclusion, exploring the impact of lifestyle and inflammation on PCa development and progression may open doors to the identification of new biomarkers. The discovery of new PCa diagnostic biomarkers should contribute to reduce overdiagnosis and overtreatment.

Dietary energy density and risk of prostate cancer: (A case-control study)

OBJECTIVE

Some observational studies investigated the association between dietary energy density (DED) and risk of cancers with inconstant results. In addition, there is no study on such association among patients with prostate cancer (PC). The present study was performed to evaluate the association between dietary energy density (DED) and PC risk.

METHODS

In this case-control study, one hundred and twenty-five participants were enrolled (62 cases and 63 controls). Dietary intakes were assessed using 160-item semi-quantitative food frequency questionnaire. In addition, demographic characteristics were collected using a general questionnaire and anthropometric indices were measured based on the available guidelines. The association between DED and PC risk was evaluated using multivariable logistic regression.

RESULTS

The results showed that higher DED score was associated with increased risk of PC (OR = 2.59; 95% CI= (1.24-5.40)). Interestingly, after adjusting for potential confounders ((smoking, physical activity, energy intake, education, ethnicity, job, anti-hyperlipidemic drugs, antihypertensive drugs, and aspirin) the results remained significant (OR = 2.87; 95% CI= (1.17-7.05)).

CONCLUSION

Our findings suggest that DED may increase the risk of PC. However, more prospective studies are warranted to confirm these results.

The incidence, mortality, and risk factors of prostate cancer in Asian men

The objective of this review was to describe the epidemiology and risk factors of prostate cancer (PCa) in Asian populations. English language publications published over the last 10 years covering studies on the incidence, mortality, and risk factors of PCa in Asia were reviewed. The incidence of PCa in Asia is rising but is still significantly lower than that in Western countries. Studies in Asia indicated that the consumption of red meat, fat, dairy, and eggs was associated with a higher risk for PCa. Age and family history were also found to be risk factors. The emergence of genetic data indicates that different genetic backgrounds between Asian and Western populations play a role in the observed differences in PCa incidence. The lower incidence of PCa in Asian men than in Western men may in part be due to a lack of systematic prostate-specific antigen screening, but environmental and genetic factors also play a role.

Latest Evidence on the Impact of Smoking, Sports, and Sexual Activity as Modifiable Lifestyle Risk Factors for Prostate Cancer Incidence, Recurrence, and Progression: A Systematic Review of the Literature by the European Association of Urology Section of Oncological Urology (ESOU)

CONTEXT

Smoking, sexual activity, and physical activity (PA) are discussed as modifiable lifestyle factors associated with prostate cancer (PCa) development and progression.

OBJECTIVE

To evaluate the available evidence concerning the association of smoking, sexual activity, and sports and exercise on PCa risk, treatment outcome, progression, and cancer-specific mortality.

EVIDENCE ACQUISITION

A systematic review of studies published between 2007 and 2017 using MEDLINE (via PubMed), Cochrane Central Register of Controlled Trials, and Web of Science databases according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis statement criteria was conducted.

EVIDENCE SYNTHESIS

While data concerning the impact of smoking on PCa development remain conflicting, there is robust evidence that smoking is associated with aggressive tumor features and worse cancer-related outcome, which seems to be maintained for 10 yr after smoking cessation. Less convincing and limited evidence exists for the association of sexual activity with PCa risk. The findings related to PA and PCa support the inference that exercise might be a useful factor in the prevention of PCa and tumor progression, while it is not finally proved under which specific conditions PA might be protective against disease development.

CONCLUSIONS

Smoking is associated with aggressive tumor features and worse cancer-related prognosis; as this negative impact seems to be maintained for 10yr after smoking cessation, urologists should advise men to quit smoking latest at PCa diagnosis to improve their prognosis. As several studies indicate a positive impact of exercise on tumor development, progression, and treatment outcome, it is certainly reasonable to advocate an active lifestyle. Least convincing evidence is available for the interaction of sexual activity and PCa, and well-conducted and longitudinal studies are clearly necessary to evaluate whether the suggested associations between PCa risk and sexual behavior are real or spurious.

PATIENT SUMMARY

In this systematic review, we looked at the impact of smoking, sexual activity, and sports and exercise on prostate cancer risk and outcome after treatment. While the evidence for sexual activity is not overall clear, we found that smoking might lead to more aggressive cancers and result in worse treatment outcome. Physical activity might prevent prostate cancer and improve cancer-related outcomes as well. Hence, it is certainly reasonable to advocate an active lifestyle and advise men to quit smoking.

Smoking increased the risk of prostate cancer with grade group ≥ 4 and intraductal carcinoma in a prospective biopsy cohort

OBJECTIVE

To investigate the association between smoking and different prostate cancer (PCa) pathological subtypes incidence in Chinese men.

PATIENTS AND METHODS

We prospectively included 1795 patients who underwent prostate biopsies in one tertiary center between March 2013 and April 2016. Clinical data and biopsy outcomes were collected. Logistic regression was used to evaluate the association between cigarette smoking and PCa incidence.

RESULTS

A total of 737 men, 480 men and 58 men were diagnosed with PCa, high-grade PCa (HGPCa, grade group ≥ 4 as accepted by the 2014 ISUP) and intraductal carcinoma of the prostate (IDC-P), respectively. Current smokers had a significantly higher risk of HGPCa than never smokers (OR = 1.89, 95%CI: 1.44-2.48). No such association was observed for low-grade disease and cigarette smoking (OR = 0.84, 95%CI: 0.61-1.16). In a sub-analysis, men who had smoked longer than 30 years had a higher risk of HGPCa, compared with men who had smoked fewer than 30 years (OR = 1.50, 95%CI: 1.09-2.06). Current smokers were more likely to develop IDC-P than never smokers (OR = 2.29, 95%CI: 1.14-4.59).

CONCLUSION

Among men in this Chinese biopsy cohort, current smoking was associated with highly malignant PCa incidence, such as HGPCa and IDC-P. The duration of smoking may be associated with HGPCa.

Associations of body mass index, smoking, and alcohol consumption with prostate cancer mortality in the Asia Cohort Consortium

Many potentially modifiable risk factors for prostate cancer are also associated with prostate cancer screening, which may induce a bias in epidemiologic studies. We investigated the associations of body mass index (weight (kg)/height (m)(2)), smoking, and alcohol consumption with risk of fatal prostate cancer in Asian countries where prostate cancer screening is not widely utilized. Analysis included 18 prospective cohort studies conducted during 1963-2006 across 6 countries in southern and eastern Asia that are part of the Asia Cohort Consortium. Body mass index, smoking, and alcohol intake were determined by questionnaire at baseline, and cause of death was ascertained through death certificates. Analysis included 522,736 men aged 54 years, on average, at baseline. During 4.8 million person-years of follow-up, there were 634 prostate cancer deaths (367 prostate cancer deaths across the 11 cohorts with alcohol data). In Cox proportional hazards analyses of all cohorts in the Asia Cohort Consortium, prostate cancer mortality was not significantly associated with obesity (body mass index >25: hazard ratio (HR) = 1.08, 95% confidence interval (CI): 0.85, 1.36), ever smoking (HR = 1.00, 95% CI: 0.84, 1.21), or heavy alcohol intake (HR = 1.00, 95% CI: 0.74, 1.35). Differences in prostate cancer screening and detection probably contribute to differences in the association of obesity, smoking, or alcohol intake with prostate cancer risk and mortality between Asian and Western populations and thus require further investigation.

Factors Associated With the Prevalence of Prostate Cancer in Rural Saskatchewan: The Saskatchewan Rural Health Study

PURPOSE

Prostate cancer is the most commonly diagnosed cancer in Canadian males, and it is the third most common cause of cancer-related deaths in men. Some studies suggest that occupational exposure may be associated with prostate cancer. However, the etiology of prostate cancer is ambiguous. The purpose of this study was to assess the rural occupational exposure, including farming, as a determinant of prostate cancer in rural men. We investigated the prevalence of prostate cancer and its putative relationship between rural exposures in the Saskatchewan province of Canada.

METHODS

In 2010, a baseline mailed survey was conducted of 11,982 households located in 4 geographic regions (southwest, southeast, northwest, and northeast) of rural Saskatchewan, Canada. The questionnaires collected information on individual and contextual determinants from a rural population of men. In total 2,938 males older than 45 years were included in the logistic regression analysis.

FINDINGS

The age-standardized prevalence of prostate cancer was 3.32%. Farm residence was a significant risk factor associated with prevalence of prostate cancer while farming occupation and duration were not. Men who were exposed to insecticides and fungicides together (OR [95% CI] = 2.23 [1.15-4.33], P = .02) at work showed an increased potential risk compared to the nonexposed. The effect of farm/nonfarm residence on prevalence of prostate cancer differed depending on personal smoking history and family history of cancer.

CONCLUSION

Workplace exposure to insecticides and fungicides together were statistically significantly associated with prevalence of prostate cancer.

A systematic review and meta-analysis of tobacco use and prostate cancer mortality and incidence in prospective cohort studies

CONTEXT

An association between tobacco smoking and prostate cancer (PCa) incidence and mortality was suggested in an earlier meta-analysis of 24 prospective studies in which dose-response associations and risks per unit of tobacco use were not examined.

OBJECTIVE

We investigated the association between several measures of tobacco use and PCa mortality (primary outcome) and incidence (secondary outcome) including dose-response association.

EVIDENCE ACQUISITION

Relevant articles from prospective studies were identified by searching the PubMed and Web of Science databases (through January 21, 2014) and reference lists of relevant articles. Combined relative risks (RRs) and 95% confidence intervals (CIs) were calculated using random effects methods. We also calculated population attributable risk (PAR) for smoking and PCa mortality.

EVIDENCE SYNTHESIS

We included 51 articles in this meta-analysis (11823 PCa deaths, 50349 incident cases, and 4,082,606 cohort participants). Current cigarette smoking was associated with an increased risk of PCa death (RR: 1.24; 95% CI, 1.18-1.31), with little evidence for heterogeneity and publication bias. The number of cigarettes smoked per day had a dose-response association with PCa mortality (p=0.02; RR for 20 cigarettes per day: 1.20). The PAR for cigarette smoking and PCa deaths in the United States and Europe were 6.7% and 9.5%, respectively, corresponding to >10000 deaths/year in these two regions. Current cigarette smoking was inversely associated with incident PCa (RR: 0.90; 95% CI, 0.85-0.96), with high heterogeneity in the results. However, in studies completed in 1995 or earlier (considered as completed before the prostate-specific antigen screening era), ever smoking showed a positive association with incident PCa (RR: 1.06; 95% CI, 1.00-1.12) with little heterogeneity.

CONCLUSIONS

Combined evidence from observational studies shows a modest but statistically significant association between cigarette smoking and fatal PCa. Smoking appears to be a modifiable risk factor for PCa death.

PATIENT SUMMARY

Smoking increases the chance of prostate cancer death. Not smoking prevents this harm and many other tobacco-related diseases.

Green and black tea intake in relation to prostate cancer risk among Singapore Chinese

PURPOSE

Tea is one of the most commonly consumed beverages worldwide. To date, observational data from prospective cohort studies investigating the relationship between green and black tea intake and prostate cancer risk are sparse and equivocal. In a population-based, prospective cohort study of Chinese men in Singapore, we investigated the relationship between green and black tea intake and prostate cancer risk.

METHODS

Tea consumption data for 27,293 men were collected at baseline (between 1993 and 1998) using a validated food frequency questionnaire. After an average of 11.2 years of follow-up, 298 men had developed prostate cancer. Proportional hazards regression methods were used to assess the associations between tea intake and prostate cancer risk.

RESULTS

There was no association between daily green tea intake and prostate cancer risk, compared with no green tea intake [hazard ratio (HR) = 1.08; 95 % confidence interval (CI) 0.79, 1.47]. For black tea, a statistically significant positive association and trend were observed for daily intake compared with no black tea intake (HR = 1.41, 95 % CI 1.03, 1.92; p for trend <0.01)

CONCLUSIONS

Few prospective data are available from populations that have both a high level and wide range of black and green tea intake; this study represents a unique opportunity to evaluate their individual effects on prostate cancer risk. Our findings support the notion that green tea intake does not protect against prostate cancer and that black tea intake may increase prostate cancer risk.

Impact of XPD gene polymorphism on risk of prostate cancer on north Indian population

Prostate cancer is the second most diagnosed cancer in men next to skin cancer in the developed world. Risk of disease varies most prominently with age, ethnicity, family history, and diet. Genetic polymorphism of some genes has been implicated in increasing the risk. The XPD (Xeroderma pigmentosum group D) gene codes for a DNA helicase involved in transcription and nucleotide excision repair. The aim of this study is to evaluate the effect of XPD 751 Lys/Gln polymorphism on risk of prostate cancer on north Indian patients. Blood sample from 150 prostate cancer patients, 150 from Prostate Hyper Plasia and equal number of samples from healthy control groups was collected from North India. The polymerase chain reaction and restrictive fragment length polymorphism techniques were implemented. Statistically non-significant increase risk of prostate cancer was observed with patients having Gln/Gln genotype (OR 1.62, 95% CI).