Reverse smoking in Andhra Pradesh, India: a study of palatal lesions among 10,169 villagers

In the district of Srikakulam in Andhra Pradesh in South India the habit of reverse smoking is widespread. In a house to house survey of oral cancer and precancerous conditions, comprising 10,169 villagers, 43·8% were reverse smokers; the female: male ratio being 1·7: 1. Ten previously undiagnosed cases of oral cancer, 9 located to palate, were found. The prevalences for leukoplakia, preleukoplakia and leukokeratosis nicotina palati were 4·9%, 2·9% and 9·5%. Of 497 leukoplakias, 422 were located to the palate and 413 of these patients had the habit of reverse smoking. Histologically, 80% of 381 palatal biopsies had a hyperorthokeratosis. Epithelial atypia was found in 15·3% of leukoplakias, in 3·6% of the preleukoplakias, and in 9·1% of leukokeratosis nicotina palati. Various explanations for the habit of reverse smoking are suggested and discussed. In addition to reverse smoking, other tobacco habits were also recorded; all habits and oral lesions were compared and have been discussed according to their apparent interrelationships and distribution by sex and age.     

Sucrose as a risk factor for cancer of the colon and rectum: A case-control study in Uruguay

In order to examine the relationship between dietary sucrose intake and colorectal cancer, a case-control study was conducted in Uruguay in the time period 1992–1996. In all, 289 cases and 564 controls, admitted for diagnosis or treatment in the 4 major hospitals in Montevideo, were considered eligible for the study. Total sucrose intake was associated with a monotonic positive gradient of risks and the odds ratio (OR) for the uppermost quartile of intake was of 2.18 (95% confidence interval, CI, 1.35–3.51). Glucose intake was associated with a small and non-significant increase in risk (OR 1.46, 95% CI 0.76–2.82). Finally, an interaction between sucrose and protein intake was found, and the OR for high intakes of sucrose and protein was 6.07. Int. J. Cancer 75:40–44, 1998.© 1998 Wiley-Liss, Inc.     

Family history of breast cancer as a risk factor for ovarian cancer in a prospective study

BACKGROUND: A family history of breast cancer has been associated with increased ovarian cancer risk. However, few studies have assessed risk according to characteristics that suggest an inherited cancer susceptibility disorder, such as earlier-than-usual age at cancer diagnosis, family members with double primary cancers of different types, multiple relatives with cancer, and cancer in both members of paired organs. METHODS: Ovarian cancer risk was assessed according to a detailed breast cancer family history among 49,975 participants in the Breast Cancer Detection Demonstration Project Breast Cancer Defection Demenstration Project (BCDDP) Follow-up Study (1979-1998). In all, 362 incident ovarian cancers were identified during follow-up and rate ratios (RRs) were calculated by Poisson regression. RESULTS.: Breast cancer in a first- or second-degree relative was associated with increased risk of ovarian cancer (RR = 1.4; 95% confidence interval [CI] = 1.1-1.7). Having 2 or more affected first-degree relatives was associated with increased risk (RR = 1.8; 95% CI = 1.1-2.8), especially for women diagnosed with ovarian cancer before age 60 (RR = 4.2; 95% CI = 1.9-9.2) or with a personal history of breast cancer (RR = 3.7; 95% CI 1.8-7.7). Risk was also particularly high for women with 2 or more first-degree relatives with breast cancer and at least 1 affected relative diagnosed before age 50 (RR = 2.6; 95% CI = 1.4-4.8) or with bilateral breast cancer (RR = 4.2; 95% CI = 1.7-10). CONCLUSIONS: A detailed breast cancer family history as well as an individual's age and personal history of breast cancer are useful for identifying women at elevated genetic risk of ovarian cancer.     

吸烟与肝癌前瞻性研究的荟萃分析

目的:探索吸烟与肝癌发生的病因学联系. 方法:利用MEDLINE数据库及中国生物医学文献数据库检索1989年1月-2009年9月国内外公开发表的关于吸烟与肝癌关系的前瞻性研究文献,利用R软件及Meta程序包对检索结果进行荟萃分析. 结果: 纳入本次荟萃分析的文献共19篇,随访队列总样本量为3 023 558人,累计肝癌病例数为9 525人.与不吸烟者相比,吸烟者经Meta分析综合后的相对危险度(relative risk,RR)值及其95%可信区间(confidence interval,CI)为1.49(1.17～1.92),提示吸烟与肝癌呈中等程度相关;亚组分析显示,男女性别经Meta分析综合后吸烟的RR值及其95%CI分别为1.53(1.29～1.83)和1.70(1.17～2.48),差异均有统计学意义. 结论:吸烟与男女性肝癌之间存在病因学联系,是肝癌发生的危险因素之一.     

Infection as a risk factor for gallbladder cancer

Gallbladder cancer is a common hepato-biliary malignancy with poor prognosis. The main associated risk factors identified so far include cholelithiasis (especially mixed gall stone), chronic infections of the gallbladder, obesity, reproductive factors, diet, hepato-biliary anamolies, and environmental exposure to specific chemicals. Genetic and molecular predisposing factors have also been described. This article reviews the association of chronic infection and gallbladder cancer. Most of the studies have shown a good association of mixed bacterial and Salmonella infections in the carcinogenesis of cancer gallbladder especially in the area of high endemicity of typhoid. Bacterial degradation of bile and chronic inflammation may also play some role in the carcinogenic process. Mutations in multiple tumor suppressor gene and oncogenes (P53 and K-ras) have also been found in a few studies. This review seeks to bring out many hidden infective etiological aspects of the pathogenesis of gallbladder cancer. Review of the entire published literature suggests a need for further studies for better understanding of the disease.     

A case‐control study on hormone therapy as a risk factor for breast cancer in Finland: Intrauterine system carries a risk as well

The purpose of this study was to evaluate the association between postmenopausal hormone therapy (HT) and the risk for breast cancer in recently postmenopausal Finnish women. All Finnish women with first invasive breast cancer diagnosed between the ages of 50 and 62 years during 1995–2007 (n = 9,956) were identified from the Finnish Cancer Registry. For each case, 3 controls of the same age were retrieved from the Finnish Population Register. The cases and controls were linked to the national medical reimbursement register to assess the use of HT. The odds ratios (ORs) and 95% confidence intervals (CIs) for breast cancer were calculated with conditional logistic regression analysis, adjusting for parity, age at the first birth and health care district. Estradiol‐only therapy (991 users with breast cancer, n) or oral progestagen (n = 138) was not accompanied by an increased risk. Estradiol‐progestagen therapy (EPT) (n = 1,731) was associated with an elevated risk in the whole series (OR 1.36; 95% CI 1.27–1.46). The risk became detectable in less than 3 years of use. Continuous EPT use tended to be associated with a higher risk for breast cancer than the sequential EPT use. The use of tibolone (n = 80) (1.36; 1.15–1.96), a levonorgestrel‐releasing intrauterine system (LNG–IUS) alone (n = 154) (1.45; 1.97–1.77) or as a complement to estradiol (n = 137) (2.15; 1.72–2.68) was also associated with an increased risk. The association between HT use and the risk for breast cancer shows a large variation between various forms of HT, and also the use of LNG‐IUS may carry a risk.     

Periodontal disease as a risk factor for sporadic colorectal cancer: results from COLDENT study

Cancer Causes & Control - Colorectal cancer remains the top leading cancer worldwide. Accumulating evidence suggests periodontal pathogens are involved in colorectal carcinogenesis, indicating...     

A genome-wide linkage study of mammographic density, a risk factor for breast cancer

Introduction

Mammographic breast density is a highly heritable (h² > 0.6) and strong risk factor for breast cancer. We conducted a genome-wide linkage study to identify loci influencing mammographic breast density (MD).

Methods

Epidemiological data were assembled on 1,415 families from the Australia, Northern California and Ontario sites of the Breast Cancer Family Registry, and additional families recruited in Australia and Ontario. Families consisted of sister pairs with age-matched mammograms and data on factors known to influence MD. Single nucleotide polymorphism (SNP) genotyping was performed on 3,952 individuals using the Illumina Infinium 6K linkage panel.

Results

Using a variance components method, genome-wide linkage analysis was performed using quantitative traits obtained by adjusting MD measurements for known covariates. Our primary trait was formed by fitting a linear model to the square root of the percentage of the breast area that was dense (PMD), adjusting for age at mammogram, number of live births, menopausal status, weight, height, weight squared, and menopausal hormone therapy. The maximum logarithm of odds (LOD) score from the genome-wide scan was on chromosome 7p14.1-p13 (LOD = 2.69; 63.5 cM) for covariate-adjusted PMD, with a 1-LOD interval spanning 8.6 cM. A similar signal was seen for the covariate adjusted area of the breast that was dense (DA) phenotype. Simulations showed that the complete sample had adequate power to detect LOD scores of 3 or 3.5 for a locus accounting for 20% of phenotypic variance. A modest peak initially seen on chromosome 7q32.3-q34 increased in strength when only the 513 families with at least two sisters below 50 years of age were included in the analysis (LOD 3.2; 140.7 cM, 1-LOD interval spanning 9.6 cM). In a subgroup analysis, we also found a LOD score of 3.3 for DA phenotype on chromosome 12.11.22-q13.11 (60.8 cM, 1-LOD interval spanning 9.3 cM), overlapping a region identified in a previous study.

Conclusions

The suggestive peaks and the larger linkage signal seen in the subset of pedigrees with younger participants highlight regions of interest for further study to identify genes that determine MD, with the goal of understanding mammographic density and its involvement in susceptibility to breast cancer.     

Tobacco smoking,alcohol consumption and pancreatic cancer risk: A case-control study in Italy

In Italy, pancreatic cancer accounts for approximately 5% of cancer-related deaths. Tobacco smoking is the major established risk factor for this cancer, whereas the role of alcohol consumption is open to debate.Between 1991 and 2008, we conducted a hospital-based case-control study on pancreatic cancer in northern Italy. Cases were 326 patients (median age 63 years) with incident pancreatic cancer admitted to major general hospitals. Controls were 652 patients (median age 63 years) with acute non-neoplastic conditions admitted to the same hospital network of cases. Multiple logistic regression was used to estimate the odds ratios (OR) and the corresponding 95% confidence intervals (CI).Pancreatic cancer was associated to current smoking (OR = 1.68; 95% CI: 1.13–2.48), and the risk rose with increasing number of cigarettes/day (OR = 2.04; 95% CI: 1.14–3.66 for ?20 cigarettes/day). No association emerged for former smokers (OR = 0.98; 95% CI: 0.66–1.45). Alcohol consumption was associated to increased pancreatic cancer risk, but ORs were significant only among heavy drinkers (ORs: 2.03 and 3.42 for 21–34 and ?35 drinks/week, respectively). Pancreatic cancer risk was 4.3-fold higher in heavy smokers (?20 cigarettes/day) and heavy drinkers (?21 drinks/week) in comparison with never smokers who drunk <7 drinks/week, which is compatible with an additive effect of these exposures.In conclusion, we found that tobacco smoking and alcohol drinking are two independent risk factors for pancreatic cancer which may be responsible for approximately one third of these cancers in our population.     

幽门螺杆菌感染与胰腺癌发病相关性的Meta分析

目的:探讨幽门螺杆菌(Helicobacter pylori,Hp)感染与胰腺癌发病的相关性。方法:收集1990年-2013年国内外公开发表的关于幽门螺杆菌感染与胰腺癌发病相关性的病例对照研究的文献,应用Review Manager4.2软件Meta分析,计算合并优势比（odd ratio,OR值）及OR值95％可信区间(confidence interval,CI),倒漏斗图法定性评价发表性偏倚。结果:共7篇相关文献入选,总样本量2641例,其中胰腺癌947例,对照组1694例,Meta分析得出幽门螺杆菌感染与胰腺癌发病合并OR值为1.40（95%CI为 1.04-1.89,Z=2.21,P=0.03）。本研究倒漏斗分析图形不对称,但经敏感性分析和计算失安全系数证明,发表性偏倚对结果有一定的影响。结论:幽门螺杆菌感染是胰腺癌发病的危险因素。     

Cigarette smoking and breast cancer risk: a population-based study in Sweden

In a Swedish population-based case-control study, smoking showed no convincing association with risk of postmenopausal breast cancer - regardless of timing or level of smoking exposure - either overall or among subgroups.     

Body mass, diabetes and smoking, and endometrial cancer risk: a follow-up study

We examined the relationship of body mass index (BMI), diabetes and smoking to endometrial cancer risk in a cohort of 36 761 Norwegian women during 15.7 years of follow-up. In multivariable analyses of 222 incident cases of endometrial cancer, identified by linkage to the Norwegian Cancer Registry, there was a strong increase in risk with increasing BMI (P-trend <0.001). Compared to the reference (BMI 20-24 kg m(-2)), the adjusted relative risk (RR) was 0.53 (95% confidence interval (CI): 0.19-1.47) for BMI<20 kg m(-2), 4.28 (95% CI: 2.58-7.09) for BMI of 35-39 kg m(-2) and 6.36 (95% CI: 3.08-13.16) for BMI>or=40 kg m(-2). Women with known diabetes at baseline were at three-fold higher risk (RR 3.13, 95% CI: 1.92-5.11) than those without diabetes; women who reported current smoking at baseline were at reduced risk compared to never smokers (RR 0.55, 95% CI: 0.35-0.86). The strong linear positive association of BMI with endometrial cancer risk and a strongly increased risk among women with diabetes suggest that any increase in body mass in the female population will increase endometrial cancer incidence.     

A case-control study of gallstones: a major risk factor for biliary tract cancer

Because of the strong association between gallstones and biliary tract cancer, we conducted a case-control study of gallstones at Niigata Cancer Center Hospital. Eighty-six cases with gallstones (33 males and 53 females) and 116 hospital controls (56 males and 60 females) were surveyed by means of a self-administered questionnaire. Gallstones were categorized into cholesterol stones (25 cases) and pigment stones (30 cases) based on the appearance of the stones. In multivariate analyses based on an unconditional logistic regression model, the risk of total gallstones was positively associated with a taste for salty food (relative risk (RR) = 2.31, 95% confidence interval (CI): 1.10-4.84), an intake of lettuce and cabbage (RR = 2.98, 95% CI: 1.47-6.06) and a family history of biliary diseases (RR = 5.63, 95% CI: 1.76-17.95), and inversely associated with an intake of salted and dried fish (RR = 0.16, 95% CI: 0.04-0.64). When analyzed by type of stones, cholesterol stones were associated with a taste for oily food (RR = 3.87, 95% CI: 1.36-11.03) and pigment stones were positively associated with professional or administrative occupation (RR = 4.74, 95% CI: 1.35-16.68) and inversely associated with a taste for less greasy food (RR = 0.28, 95% CI: 0.10-0.83). Some of these results are consistent with the results of our previous study on biliary tract cancer.     

Tobacco as a risk factor in bladder cancer

A case-control study concerning smoking habits has been performedto determine risk factors for bladder cancer. The populationattributable risk (AP) for cigarettes, cigars/cigarillos, chewingtobacco and pipe yielded a statistical explanation of 33%, 23%,9% and 17%, respectively. A logistic regression analysis revealedcigarette smoking as the most pronounced determinant with anindependent effect beyond the other smoking variables correspondingto a relative risk (RR) of 2.15. The life-time consumption ofall kinds of tobacco showed a positive dose-response relationshipto risk for bladder cancer.     

Mammographic density as a risk factor for breast cancer in a low risk population

Background: Mammographic density is a function of abundance of epithelial and connective tissue in breast. It has been identified as an independent risk factor for breast cancer in studies in western populations. We conducted a case control study to evaluate the role of mammographic density as risk factor for the development of breast cancer in Indian patients. Methods: One hundred and one cases of breast cancer and 123 healthy controls were included in the study. Mammographic density of the breast tissue of all controls and the contralateral breast of breast cancer patients was measured using a six category scale by a qualified radiologist. Results: A low prevalence of dense mammographic patterns (16.3% in controls and 26.7% in cases) was seen in the study population. Premenopausal women with breast density of 50% or more had 3.8 times risk of developing breast cancer than women with breast density of Conclusion: High mammographic density patterns are associated with an increased risk for the development of breast cancer in younger women in a low risk population, whereas no such increase in risk is seen in postmenopausal women.