Coffee consumption and risk of colorectal cancer: a meta-analysis of case–control studies

A meta-analysis of case–control studies on coffee consumption and colorectal cancer risk was conducted. Twenty-four eligible studies published before May 2010 were identified, including a total of 14,846 cases of colorectal, colon or rectal cancer. Compared to non/occasional drinkers, the odds ratios (OR) for drinkers were 0.83 (95% CI 0.73–0.95) for colorectal, 0.93 (95% CI 0.81–1.07) for colon and 0.98 (95% CI 0.85–1.13) for rectal cancer, with significant heterogeneity among studies; the corresponding ORs for the increment of 1 cup/day were 0.94 (95% CI 0.91–0.98), 0.95 (95% CI 0.92–0.98), and 0.97 (95% CI 0.95–0.99). For the highest coffee drinkers, the ORs were 0.70 (95% CI 0.60–0.81) for colorectal cancer, 0.75 (95% CI 0.64–0.88) for colon cancer and 0.87 (95% CI 0.75–1.00) for rectal cancer, when compared to non/low drinkers. The results of this meta-analysis of case–control studies suggest a moderate favorable effect of coffee consumption on colorectal cancer risk. The reduced risk was consistent across study design (hospital vs. population based), geographic area, and various confounding factors considered. It may reflect a real protection but also partly or largely be due to reverse causation, i.e. decreased coffee consumption among cases following the onset of bowel symptoms.     

Sinonasal cancer and occupational exposures: a pooled analysis of 12 case–control studies

Objective: In order to examine the associations between sinonasal cancer and occupational exposures other than wood dust and leather dust, the data from 12 case–control studies conducted in seven countries were pooled and reanalyzed. Methods: The pooled data set included 195 adenocarcinoma cases (169 men and 26 women), 432 squamous cell carcinomas (330 men and 102 women), and 3136 controls (2349 men and 787 women). Occupational exposures to formaldehyde, silica dust, textile dust, coal dust, flour dust, asbestos, and man-made vitreous fibers were assessed with a job-exposure matrix. Odds ratios (ORs) were adjusted for age, study, wood dust, and leather dust, or other occupational exposures when relevant. 95% confidence intervals (CIs) were estimated by unconditional logistic regression. Results: A significantly increased risk of adenocarcinoma was associated with exposure to formaldehyde. The ORs for the highest level of exposure were 3.0 (CI = 1.5–5.7) among men and 6.2 (CI = 2.0–19.7) among women. An elevated risk of squamous cell carcinoma was observed among men (OR = 2.5, CI = 0.6–10.1) and women (OR = 3.5, CI = 1.2–10.5) with a high probability of exposure to formaldehyde. Exposure to textile dust was associated with non-significantly elevated risk of adenocarcinoma, among women only: the OR for the high level of cumulative exposure was 2.5 (CI = 0.7–9.0). High level of asbestos exposure was associated with a significantly increased risk of squamous cell carcinoma among men (OR = 1.6, CI = 1.1–2.3). Conclusions: The results of this pooled analysis support the hypothesis that occupational exposure to formaldehyde increases the risk of sinonasal cancer, particularly of adenocarcinoma. They also indicate an elevated risk of adenocarcinoma among women exposed to textile dust, and suggest that exposure to asbestos may increase the risk of squamous cell carcinoma.     

Diabetes and risk of pancreatic cancer: a pooled analysis of three large case–control studies

Racial differences in diabetes-associated pancreatic cancer (PC) and the interaction of diabetes with other risk factors are not well established. We determined the association between diabetes and risk of PC in 2,192 cases and 5,113 controls in three large case–control studies conducted at the National Cancer Institute, the University of California San Francisco, and the M.D. Anderson Cancer Center. In multivariable analyses, diabetes was associated with a 1.8-fold risk of PC [95% confidence interval (CI) = 1.5–2.1]. Risk estimates decreased with increasing years with diabetes (≤2 years OR = 2.9, 95% CI = 2.1–3.9; 3–5 years OR = 1.9, 95% CI = 1.3–2.6; 6–10 years OR = 1.6, 95% CI = 1.2–2.3; 11–15 years OR = 1.3, 95% CI = 0.9–2.0; > 15 years OR = 1.4, 95% CI = 1.0–2.0 (p for trend < 0.0001). Among diabetics, risk was higher in insulin ever users compared with nonusers (OR = 2.2, 95% CI = 1.6–3.7) and was restricted to insulin use of ≤3 years (OR = 2.4). Insulin use of >10 years was associated with a reduced risk of pancreatic cancer (OR = 0.5, 95% CI = 0.3–0.9; p for trend < 0.0001). Hispanic men and Asians had a higher risk of diabetes-associated PC than did whites and blacks, but the differences were not statistically significant. No significant interaction between diabetes and cigarette smoking, alcohol consumption and body mass index was observed. Although reverse causation may explain the association between diabetes diagnosed in close temporal proximity to PC, our results show that long-term diabetes, even though risk diminishes over time, remains a risk factor for PC independent of obesity and smoking.     

A pooled analysis of case–control studies of thyroid cancer: cigarette smoking and consumption of alcohol, coffee, and tea

Objective: To analyze the role of smoking, alcohol, coffee and tea in relation to thyroid cancer, we conducted a pooled analysis of 14 case–control studies conducted in the United States, Europe, and Asia. Methods: The sample consisted of 2725 thyroid cancer cases (2247 females, 478 males) and 4776 controls (3699 females, 1077 males). Conditional logistic regression with stratification on study, age at diagnosis, and gender was used to compute odds ratios and 95% confidence intervals. Results: Thyroid cancer risk was reduced in persons who had ever smoked. The relationship was more pronounced in current smokers (OR = 0.6, 95% CI = 0.6–0.7) than former smokers (OR = 0.9, 95% CI = 0.8–1.1). There were significant trends of reduced risk with greater duration and frequency of smoking. For consumption of wine and beer, there was a significant trend of decreasing thyroid cancer risk (p = 0.02) that was not maintained after adjustment for current smoking (p = 0.12). Thyroid cancer risk was not associated with consumption of coffee or tea. These findings were consistent in both gender-specific and histology-specific (papillary and follicular) analyses. Conclusions: Pooled analyses of these geographically diverse case–control data indicate a reduced thyroid cancer risk associated with current smoking. A reduced risk associated with alcohol was eliminated after adjustment for smoking, and caffeinated beverages did not alter thyroid cancer risk.     

Pancreatitis and pancreatic cancer in two large pooled case–control studies

Objective  

The association between duration of pancreatitis and pancreatic cancer has not been well characterized in large population-based studies. We conducted detailed analyses to determine the association between pancreatitis onset and pancreatic cancer risk.     

Postmenopausal hormone therapy and non-Hodgkin lymphoma: a pooled analysis of InterLymph case–control studies

BackgroundNon-Hodgkin lymphoma (NHL) subtypes, diffuse large B-cell (DLBCL) and follicular lymphoma (FL) have different sex ratios and are diagnosed at ages over 60 years; DLBCL is more common in men and diagnosed at older ages than FL, which occurs more among women. This analysis of postmenopausal women examines the relationship between postmenopausal hormone therapy and NHL.DesignSelf-reported use of postmenopausal hormone therapy from 2094 postmenopausal women with NHL and 2731 without were pooled across nine case–control studies (1983–2005) from North America, Europe and Japan. Study-specific odds ratios (OR) and 95% confidence intervals (CI) estimated using logistic regression were pooled using random-effects meta-analyses.ResultsPostmenopausal women who used hormone therapy were at decreased risk of NHL (pooled OR = 0.79, 95% CI 0.69–0.90). Risks were reduced when the age of starting was 50 years or older. There was no clear trend with number of years of use. Current users were at decreased risk while those stopping over 2 years before diagnosis were not. Having a hysterectomy or not did not affect the risk. Favourable effects were present for DLBCL (pooled OR = 0.66, 95% CI 0.54–0.80) and FL (pooled OR = 0.82, 95% CI 0.66–1.01).ConclusionPostmenopausal hormone therapy, particularly used close to menopause, is associated with a decreased risk of NHL.     

Plasma vitamins E and A and risk of bladder cancer: a case–control analysis

Objective  Current results on the association between serum micronutrients and bladder cancer risk have been inconsistent. We assessed plasma vitamin E (α-tocopherol, and γ-tocopherol), vitamin A (retinol), and bladder cancer risk using data collected from a case-control study. Methods  Epidemiologic data were collected via in-person interview. Plasma concentrations of α-tocopherol, γ-tocopherol, and retinol were determined by a high-performance liquid chromatography assay. Multivariate logistic regression analyses were used to estimate bladder cancer risk in association with plasma vitamins E and A. Results  386 bladder cancer patients and 389 age-, gender-, and ethnicity-matched controls were included in the study. The mean plasma α-tocopherol and retinol were significantly lower in cases than in controls (α-tocopherol: 23.93 μg/ml vs. 27.48 μg/ml, P < 0.001; retinol: 1.41 μg/ml vs. 1.53 μg/ml, P < 0.001). There was a significant reduction in bladder cancer risk associated with increasing plasma α-tocopherol level (Adjusted OR: 0.91; 95% CI: 0.85–0.97). In quartile analysis, using subjects with the lowest α-tocopherol level as the reference group, the adjusted ORs and 95% CIs for the second, third, and fourth quartiles were 0.75 (0.50–1.14), 0.69 (0.46–1.05), and 0.50 (0.32–0.78), respectively (P for trend = 0.003). Increased retinol level was also associated with reduced risk with OR of 0.57 (95% CI: 0.40–0.81). The ORs and 95% CIs for the second, third, and fourth quartiles were 0.92 (0.61–1.39), 0.66 (0.43–1.01), and 0.62 (0.40–0.95), respectively, with significant dose-response trend (P for trend = 0.01). Finally, there were significant correlations between plasma levels and dietary intakes for the three micronutrients. Conclusion  Our results suggest potential protective effect of α-tocopherol and retinol on bladder cancer risk. Future large prospective studies are needed to confirm the findings. Supported by NCI grants CA 74880 and CA 91846 All participants included have signed an informed consent to participate in this study. The authors declare no conflict of interest.     

Smoking and cervical cancer: pooled analysis of the IARC multi-centric case–control study

BACKGROUND: Smoking has long been suspected to be a risk factor for cervical cancer. However, not all previous studies have properly controlled for the effect of human papillomavirus (HPV) infection, which has now been established as a virtually necessary cause of cervical cancer. To evaluate the role of smoking as a cofactor of progression from HPV infection to cancer, we performed a pooled analysis of 10 previously published case-control studies. This analysis is part of a series of analyses of cofactors of HPV in the aetiology of cervical cancer. METHODS: Data were pooled from eight case-control studies of invasive cervical carcinoma (ICC) and two of carcinoma in situ (CIS) from four continents. All studies used a similar protocol and questionnaires and included a PCR-based evaluation of HPV DNA in cytological smears or biopsy specimens. Only subjects positive for HPV DNA were included in the analysis. A total of 1463 squamous cell ICC cases were analyzed, along with 211 CIS cases, 124 adeno- or adeno-squamous ICC cases and 254 control women. Pooled odds ratios (OR) and 95% confidence intervals (CI) were estimated using logistic regression models controlling for sexual and non-sexual confounding factors. RESULTS: There was an excess risk for ever smoking among HPV positive women (OR 2.17 95%CI 1.46-3.22). When results were analyzed by histological type, an excess risk was observed among cases of squamous cell carcinoma for current smokers (OR 2.30, 95%CI 1.31-4.04) and ex-smokers (OR 1.80, 95%CI 0.95-3.44). No clear pattern of association with risk was detected for adenocarcinomas, although the number of cases with this histologic type was limited. CONCLUSIONS: Smoking increases the risk of cervical cancer among HPV positive women. The results of our study are consistent with the few previously conducted studies of smoking and cervical cancer that have adequately controlled for HPV infection. Recent increasing trends of smoking among young women could have a serious impact on cervical cancer incidence in the coming years.     

Dietary folates and cancer risk in a network of case–control studies

BackgroundFolate deficiency leads to DNA damage and inadequate repair, caused by a decreased synthesis of thymidylate and purines. We analyzed the relationship between dietary folate intake and the risk of several cancers.Patients and methodsThe study is based on a network of case–control studies conducted in Italy and Switzerland in 1991–2009. The odds ratios (ORs) for dietary folate intake were estimated by multiple logistic regression models, adjusted for major identified confounding factors.ResultsFor a few cancer sites, we found a significant inverse relation, with ORs for an increment of 100 μg/day of dietary folate of 0.65 for oropharyngeal (1467 cases), 0.58 for esophageal (505 cases), 0.83 for colorectal (2390 cases), 0.72 for pancreatic (326 cases), 0.67 for laryngeal (851 cases) and 0.87 for breast (3034 cases) cancers. The risk estimates were below unity, although not significantly, for cancers of the endometrium (OR = 0.87, 454 cases), ovary (OR = 0.86, 1031 cases), prostate (OR = 0.91, 1468 cases) and kidney (OR = 0.88, 767 cases), and was 1.00 for stomach cancer (230 cases). No material heterogeneity was found in strata of sex, age, smoking and alcohol drinking.ConclusionsOur data support a real inverse association of dietary folate intake with the risk of several common cancers.     

Citrus fruit and cancer risk in a network of case–control studies

Background

Citrus fruit has shown a favorable effect against various cancers. To better understand their role in cancer risk, we analyzed data from a series of case–control studies conducted in Italy and Switzerland.

Patients and methods

The studies included 955 patients with oral and pharyngeal cancer, 395 with esophageal, 999 with stomach, 3,634 with large bowel, 527 with laryngeal, 2,900 with breast, 454 with endometrial, 1,031 with ovarian, 1,294 with prostate, and 767 with renal cell cancer. All cancers were incident and histologically confirmed. Controls were admitted to the same network of hospitals for acute, nonneoplastic conditions. Odds ratios (OR) were estimated by multiple logistic regression models, including terms for major identified confounding factors for each cancer site, and energy intake.

Results

The ORs for the highest versus lowest category of citrus fruit consumption were 0.47 (95% confidence interval, CI, 0.36–0.61) for oral and pharyngeal, 0.42 (95% CI, 0.25–0.70) for esophageal, 0.69 (95% CI, 0.52–0.92) for stomach, 0.82 (95% CI, 0.72–0.93) for colorectal, and 0.55 (95% CI, 0.37–0.83) for laryngeal cancer. No consistent association was found with breast, endometrial, ovarian, prostate, and renal cell cancer.

Conclusions

Our findings indicate that citrus fruit has a protective role against cancers of the digestive and upper respiratory tract.     

A pooled analysis of case–control studies of thyroid cancer. IV. Benign thyroid diseases

Objective: To obtain more precise estimates of the association between thyroid cancer and benign thyroid diseases and to elucidate the role of potential confounders or effect modifiers.Methods: The original data from 12 case–control studies from the United States, Asia, and Europe were pooled. Based on 2094 women and 425 men with cancer of the thyroid and, respectively, 3248 and 928 control subjects, odds ratios (ORs) and the corresponding 95% confidence intervals (CIs) were obtained by conditional regression models, conditioning on study and age at diagnosis, and adjusting for age and radiotherapy.Results: A history of hypothyroidism was not associated with cancer risk (pooled ORs=0.9, 95% confidence interval, CI: 0.7–1.3 in women and 1.7, 95% CI: 0.3–11.7 in men). ORs for hyperthyroidism were 1.4 (95% CI: 1.0–2.1) in women and 3.1 (95% CI: 1.0–9.8) in men. In women, however, risk was lower in the absence of or after allowance for history of goiter. Pooled ORs for a history of goiter were 5.9 (95% CI: 4.2–8.1) in women and 38.3 (95% CI: 5.0–291.2) in men. Risk for a history of benign nodules/adenomas was especially high (OR=29.9, 95% CI: 14.5–62.0, in women; 18 cases versus 0 controls in men). The excess risk for goiter and benign nodules/adenomas was greatest within 2–4 years prior to thyroid cancer diagnosis, but an elevated OR was present 10 years or more before cancer.Conclusions: Goiter and benign nodules/adenomas are the strongest risk factors for thyroid cancer, apart from radiation in childhood.     

Processed meat consumption and risk of cancer: a multisite case–control study in Uruguay

Background:

The role of processed meat in the aetiology of several cancers was explored in detail.

Methods:

In the time period 1996–2004, a multisite case–control study was conducted in Montevideo, Uruguay. The study included 6 060 participants (3 528 cases and 2 532 controls) corresponding to cancers of the oral cavity, pharynx, oesophagus, stomach, colon, rectum, larynx, lung, female breast, prostate, urinary bladder, and kidney (renal cell carcinoma only).

Results:

The highest odds ratios (ORs) were positively associated with cancers of the colon, rectum, stomach, oesophagus, and lung. With the exception of renal cell carcinoma, the remaining cancer sites were significantly associated with elevated risks for processed meat consumption. Furthermore, mortadella, salami, hot dog, ham, and salted meat were strongly associated with risk of several cancer sites.

Conclusion:

It could be concluded that processed meat intake could be a powerful multiorgan carcinogen.     

Urinary tract diseases and bladder cancer risk: a case–control study

Objective The role of urinary tract diseases in bladder cancer (BC) etiology is not well established. To gain more insight on the role of urinary tract diseases in bladder cancer risk, we analyzed data from a large case–control study of bladder cancer. Methods Epidemiological data were collected via in-person interview. Logistic regression analyses were used to estimate BC risk in association with prior history of urinary tract diseases. Results A total of 659 BC patients and 689 age-, gender-, -ethnicity matched controls were included in the analyses. Increased bladder cancer risk was associated with history of cystitis (OR = 1.52, 95% CI: 1.12, 2.06), however, the risk was attenuated for infections diagnosed >1 year from the time of BC diagnosis or interview. In contrast, a history of four or more kidney infections was associated with a significant decreased risk of BC (OR=0.17, 95% CI: 0.04, 0.69), and there was a significant dose-response relationship between number of episode and BC risk (P for trend = 0.002). The joint effect of smoking with cystitis, kidney infection, bladder stone, kidney stone, and prostate infection was studied but revealed no significant interaction between smoking and these urinary tract diseases. Conclusion This study does not support the concept that urinary tract infections play a major role in the development of BC. Our study has the strength of collecting diagnosis time data of urinary tract diseases to allow analyzing the impact of timing of diagnosis between cancer and urinary tract diseases. This enables us to effectively address the issue of detection bias in case–controls studies of prior urinary diseases and BC.     

Phytoestrogen consumption and endometrial cancer risk: a population-based case–control study in New Jersey

Phytoestrogens have been shown to exert anti-estrogenic and estrogenic effects in some tissues, including the breast. However, only a few studies have evaluated their role in endometrial cancer risk. We evaluated this association in a population-based case–control study in New Jersey. A total of 424 cases and 398 controls completed an interview, including a food frequency questionnaire with supplemental questions for phytoestrogen foods. Risk estimates were derived using an unconditional logistic regression, adjusting for major risk factors for endometrial cancer. There was some suggestion of a decreased risk with quercetin intake (OR: 0.65; 95% CI: 0.41–1.01 for the highest compared to the lowest quartile; p for trend: 0.02). We found a limited evidence of an association with any of the lignans evaluated, total lignans, coumestrol, individual isoflavones, total isoflavones, or total phytoestrogens. However, there was some suggestion of an inverse association with total isoflavone intake limited to lean women (BMI <25; OR for the highest tertile: 0.50; 95% CI: 0.25–0.98) and those with a waist-to-hip ratio ≤0.85 (OR: 0.59; 95% CI: 0.33–1.05). There was no evidence of effect modification by HRT use. This study suggests a reduction in endometrial cancer risk with quercetin intake and with isoflavone intake in lean women.     

Physical activity and risk of pancreatic cancer in a central European multicenter case–control study

Purpose

Findings from epidemiological studies examining physical activity in relation to pancreatic cancer risk have suggested decreased risks for physical activity; however, the results are inconsistent.

Methods

The association between occupational and leisure-time physical activity and risk of pancreatic cancer was examined among 826 pancreatic cancer cases and 930 age-, sex- and center-matched controls from a large multicenter central European study in Czech Republic and Slovakia recruited between 2004 and 2012. Data on physical activity including type and dose (frequency, intensity, and duration) were examined using multivariable-adjusted logistic regression models.

Results

Occupational physical activity was not significantly associated with risk of pancreatic cancer [odds ratio (OR) 0.90, 95 % confidence interval (CI) 0.71–1.15]. A 35 % decrease in risk of pancreatic cancer was observed for regular leisure-time physical activity (OR 0.65, 95 % CI 0.52–0.87). The risk estimates were significant for low and moderate intensity of activity with the strongest protective effect among individuals who exercised during more than 40 weeks per year. The results for cumulated leisure-time physical activity assessed 1 year prior to diagnosis achieved the same level of risk reduction. In addition, stronger risk estimates for leisure-time physical activity were observed among women (men: OR 0.74, 95 % CI 0.54–1.01; women: OR 0.53, 95 % CI 0.37–0.75). The findings for female participants were stronger for intensity and frequency of leisure-time physical activity, in particular for light and moderate activity (OR 0.43, 95 % CI 0.25–0.75; and OR 0.57, 95 % CI 0.37–0.88, respectively).

Conclusion

These results provide evidence for a decreased risk of pancreatic cancer associated with regular leisure-time physical activity.     

Alcohol consumption and risk of myelodysplastic syndromes: a case–control study

Purpose

Epidemiological studies on alcohol consumption and the risk of myelodysplastic syndromes (MDS) have been inconclusive. We evaluated the association between alcohol consumption and MDS risk in a Chinese population.

Methods

A hospital-based case–control study was conducted between 2012 and 2013 in Hangzhou, China. The analysis included 208 case–control pairs. Diagnosis of MDS was confirmed according to the 2008 World Health Organization classification system. Controls were individually matched to the cases by gender, birth quinquennium, and residential locality. Information on habitual alcohol consumption, diet, and lifestyle was sought from face-to-face interview using a validated questionnaire. Odds ratios (ORs) were calculated using conditional logistic regression.

Results

Fewer cases (36.5 %) were classified as alcohol drinkers compared with the controls (48.6 %). Compared with abstainers, the adjusted OR for alcohol drinkers was 0.41 (95 % CI 0.21–0.80), and significant reduced risks were found for light alcohol consumption (≤12.5 g/day of ethanol) and for wine consumption, adjusted ORs (95 % CIs) being 0.27 (0.12–0.61) and 0.12 (0.02–0.79), respectively. Compared with individuals who consumed neither alcohol nor cigarettes, the reduced risk associated with light alcohol consumption was only statistically significant among non-smokers (OR 0.19, 95 % CI 0.06–0.60).

Conclusions

The findings suggest a favorable role of light alcohol consumption in MDS, particularly among non-smokers.

     

Methylenetetrahydrofolate reductase polymorphisms and breast cancer risk in Chinese population: a meta-analysis of 22 case–control studies

The association between methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms and breast cancer risk in the Chinese population has been widely reported, but results were inconsistent. In order to derive a more precise estimation of the relationship, a meta-analysis was performed. Eligible articles were identified through search of databases including Medline, PubMed, Web of Science, Embase, Chinese Biomedical Literature Database (CBM, Chinese), China National Knowledge Infrastructure (CNKI, Chinese), and Wangfang Database (Chinese). The association between the MTHFR polymorphism and breast cancer risk was conducted using odds ratios (ORs) and 95 % confidence intervals (95 % CIs). Finally, a total of 22 studies with 6,103 cases and 7,913 controls were included in our meta-analysis: 13 studies with 3,273 cases and 4,419 controls for C677T polymorphism and 9 studies with 2,830 cases and 3,494 controls for A1298C polymorphism. With regard to C677T polymorphism, significant association was found with breast cancer risk under three models (T vs. C: OR?=?1.12, 95 % CI?=?1.02–1.23, P?=?0.015; TT vs. CC: OR?=?1.35, 95 % CI?=?1.10–1.67, P?=?0.005; TT vs. CC/CT: OR?=?1.37, 95 % CI?=?1.11–1.70, P?=?0.004). There was no significant association found between A1298C polymorphism and breast cancer risk under all genetic models (C vs. A: OR?=?0.96, 95 % CI?=?0.89–1.03, P?=?0.268; CC vs. AA: OR?=?0.98, 95 % CI?=?0.77–1.26, P?=?0.899; AC vs. AA: OR?=?0.95, 95 % CI?=?0.88–1.02, P?=?0.174; CC vs. AC/AA: OR?=?1.00, 95 % CI?=?0.78–1.28, P?=?0.996, CC/AC vs. AA: OR?=?0.96, 95 % CI?=?0.89–1.02, P?=?0.196). In summary, during this meta-analysis, we found that MTHFR C677T polymorphism was significantly associated with breast cancer risk in the Chinese population. Meanwhile, MTHFR A1298C polymorphism was not associated with breast cancer risk in the Chinese population.     

Red meat and cancer risk in a network of case–control studies focusing on cooking practices

BackgroundConsumption of red meat has been related to increased risk of several cancers. Cooking methods could modify the magnitude of this association, as production of chemicals depends on the temperature and duration of cooking.MethodsWe analyzed data from a network of case–control studies conducted in Italy and Switzerland between 1991 and 2009. The studies included 1465 oral and pharyngeal, 198 nasopharyngeal, 851 laryngeal, 505 esophageal, 230 stomach, 1463 colon, 927 rectal, 326 pancreatic, 3034 breast, 454 endometrial, 1031 ovarian, 1294 prostate and 767 renal cancer cases. Controls included 11 656 patients admitted for acute, non-neoplastic conditions. Odds ratios (ORs) and confidence intervals (CIs) were estimated by multiple logistic regression models, adjusted for known confounding factors.ResultsDaily intake of red meat was significantly associated with the risk of cancer of the oral cavity and pharynx (OR for increase of 50 g/day = 1.38; 95% CI: 1.26–1.52), nasopharynx (OR = 1.29; 95% CI: 1.04–1.60), larynx (OR = 1.46; 95% CI: 1.30–1.64), esophagus (OR = 1.46; 95% CI: 1.23–1.72), colon (OR = 1.17; 95% CI: 1.08–1.26), rectum (OR = 1.22; 95% CI:1.11–1.33), pancreas (OR = 1.51; 95% CI: 1.25–1.82), breast (OR = 1.12; 95% CI: 1.04–1.19), endometrium (OR = 1.30; 95% CI: 1.10–1.55) and ovary (OR = 1.29; 95% CI: 1.16–1.43). Fried meat was associated with a higher risk of cancer of oral cavity and pharynx (OR = 2.80; 95% CI: 2.02–3.89) and esophagus (OR = 4.52; 95% CI: 2.50–8.18). Risk of prostate cancer increased for meat cooked by roasting/grilling (OR = 1.31; 95% CI: 1.12–1.54). No heterogeneity according to cooking methods emerged for other cancers. Nonetheless, significant associations with boiled/stewed meat also emerged for cancer of the nasopharynx (OR = 1.97; 95% CI: 1.30–3.00) and stomach (OR = 1.86; 95% CI: 1.20–2.87).ConclusionsOur analysis confirmed red meat consumption as a risk factor for several cancer sites, with a limited impact of cooking methods. These findings, thus, call for a limitation of its consumption in populations of Western countries.     

Association between CCND1 and XPC polymorphisms and bladder cancer risk: a meta-analysis based on 15 case–control studies

Perturbations in cell cycle and DNA repair genes might affect susceptibility to cancer. The aim of this meta-analysis is to generate large-scale evidence to determine the degree to which common Cyclin D1 (CCND1) G870A (dbSNP: rs603965) and xeroderma pigmentosum group C (XPC) Ala499Val (dbSNP: rs2228000) polymorphisms are associated with susceptibility to bladder cancer. The electronic databases PubMed, Embase, Web of Science, and CNKI were searched for relevant studies (with an upper date limit of July 25, 2013). The principal outcome measure for evaluating the strength of association was crude odds ratios (ORs) along with their corresponding confidence intervals (95 %CIs). We found and reviewed nine case–control studies on CCND1 G870A with a total of 6,823 subjects and seven studies on XPC Ala499Val with a total of 7,674 subjects. Our meta-analysis provides evidence that the variant genotype of CCND1 G870A showed a significant association in the occurrence of invasive bladder tumors in former and current smokers. The XPC Ala499Val polymorphism correlated with significant differences between patients and unaffected subjects, but when the groups were stratified by ethnicity, the magnitude of the overall effect was similar only among Caucasian populations. Results from our meta-analysis support the view that the G870A polymorphism may modulate the risk of bladder cancer in conjunction with tobacco smoking and that the Ala499Val polymorphism may contribute to the susceptibility to bladder cancer in Caucasian populations. Our findings, however, warrant larger well-designed studies to investigate the significance of these two polymorphisms as markers of susceptibility to bladder cancer.