Periodontal diseases and risk of oral cancer in Southern India: Results from the HeNCe Life study

Some studies suggest that periodontal diseases increase the risk of oral cancer, but contradictory results also exist. Inadequate control of confounders, including life course exposures, may have influenced prior findings. We estimate the extent to which high levels of periodontal diseases, measured by gingival inflammation and recession, are associated with oral cancer risk using a comprehensive subset of potential confounders and applying a stringent adjustment approach. In a hospital‐based case‐control study, incident oral cancer cases (N = 350) were recruited from two major referral hospitals in Kerala, South India, from 2008 to 2012. Controls (N = 371), frequency‐matched by age and sex, were recruited from clinics at the same hospitals. Structured interviews collected information on several domains of exposure via a detailed life course questionnaire. Periodontal diseases, as measured by gingival inflammation and gingival recession, were evaluated visually by qualified dentists following a detailed protocol. The relationship between periodontal diseases and oral cancer risk was assessed by unconditional logistic regression using a stringent empirical selection of potential confounders corresponding to a 1% change‐in‐estimates. Generalized gingival recession was significantly associated with oral cancer risk (Odds Ratio = 1.83, 95% Confidence Interval: 1.10–3.04). No significant association was observed between gingival inflammation and oral cancer. Our findings support the hypothesis that high levels of periodontal diseases increase the risk of oral cancer.     

Use of glucosamine and chondroitin supplements in relation to risk of colorectal cancer: Results from the Nurses' Health Study and Health Professionals follow‐up study

Recent epidemiologic evidence has emerged to suggest that use of glucosamine and chondroitin supplements may be associated with reduced risk of colorectal cancer (CRC). We therefore evaluated the association between use of these non‐vitamin, non‐mineral supplements and risk of CRC in two prospective cohorts, the Nurses' Health Study and Health Professionals Follow‐up Study. Regular use of glucosamine and chondroitin was first assessed in 2002 and participants were followed until 2010, over which time 672 CRC cases occurred. Cox proportional hazards regression was used to estimate relative risks (RRs) within each cohort, and results were pooled using a random effects meta‐analysis. Associations were comparable across cohorts, with a RR of 0.79 (95% CI: 0.63–1.00) observed for any use of glucosamine and a RR of 0.77 (95% CI: 0.59–1.01) observed for any use of chondroitin. Use of glucosamine in the absence of chondroitin was not associated with risk of CRC, whereas use of glucosamine + chondroitin was significantly associated with risk (RR: 0.77; 95% CI: 0.58–0.999). The association between use of glucosamine + chondroitin and risk of CRC did not change markedly when accounting for change in exposure status over follow‐up (RR: 0.75; 95% CI: 0.58–0.96), nor did the association significantly vary by sex, aspirin use, body mass index, or physical activity. The association was comparable for cancers of the colon and rectum. Results support a protective association between use of glucosamine and chondroitin and risk of CRC. Further study is needed to better understand the chemopreventive potential of these supplements.     

Lobule type and subsequent breast cancer risk: Results from the Nurses' Health Studies

BACKGROUND:

Lobules in normal breast tissue can be classified based on their degree of development, which may affect their susceptibility to carcinogenesis. However, few epidemiologic studies to date have addressed this.

METHODS:

The authors examined the association between lobule type and subsequent breast cancer risk in a nested case‐control study of benign breast disease (BBD) and breast cancer within the Nurses' Health Studies (200 cases, 915 controls). Benign breast biopsy slides were reviewed by pathologists, and normal terminal duct lobular units were classified as having no type 1 lobules, mixed lobule types, or predominant type 1 and no type 3 lobules. Logistic regression was used to compute odds ratios (ORs) and 95% confidence intervals (CIs) for the association between lobule type and breast cancer risk.

RESULTS:

Women with predominant type 1 and no type 3 lobules (54 cases, 321 controls) had a decreased risk of breast cancer compared with those with no type 1 lobules or mixed lobule types (OR=0.63; 95% CI, 0.44‐0.91), although this was attenuated after adjustment for histologic category of BBD (OR=0.71; 95% CI, 0.49‐1.02). Having predominant type 1 lobules and no type 3 lobules was associated with a similar risk reduction for all categories of BBD (nonproliferative: OR=0.73 [95% CI, 0.36‐1.50]; proliferative without atypia: OR=0.80 [95% CI, 0.47‐1.35]; and atypical hyperplasia: OR=0.61 [95% CI, 0.28‐1.35]).

CONCLUSIONS:

These results provided preliminary evidence that lobule type may be an important marker of breast cancer risk in women with BBD. Cancer 2009. © 2009 American Cancer Society.     

Antioxidant intake and risk of endometrial cancer: Results from the Nurses' Health Study

To investigate the associations between antioxidant intake and risk of endometrial cancer, the authors analyzed data from the prospective Nurses' Health Study. From 1980 to 2006, 669 invasive adenocarcinoma cases were identified over 1.3 million person‐years of follow‐up. Information on dietary intake was collected in 1980 and updated every 2–4 years. Cox proportional hazard models were used to calculate the multivariate relative risks (RR), controlling for total energy and potential risk factors for endometrial cancer. Overall, the authors found no association between intakes of vitamins A, C, E or carotenoids from foods or supplements and cancer risk. The RR and 95% confidence intervals (CI) for the highest vs. lowest quintiles of vitamins A, C, E and total carotenoids were 1.09 (95% CI: 0.85–1.39), 0.98 (95% CI: 0.76–1.25), 1.07 (95% CI: 0.83–1.38) and 1.12 (95% CI: 0.86–1.45), respectively. Similarly, the use of multivitamins or specific vitamins A, C or E supplements was unassociated with risk. In subgroup analyses, several associations seemed to vary by postmenopausal hormone use. Our results suggest that there is no overall association between dietary antioxidant intake or use of antioxidant supplements with risk of endometrial cancer.     

Epoxide hydrolase and CYP2C9 polymorphisms, cigarette smoking, and risk of colorectal carcinoma in the Nurses' Health Study and the Physicians' Health Study

Microsomal epoxide hydrolase (mEH) and cytochrome P450 2C9 (CYP2C9) are involved in the bioactivation and detoxification of polycyclic aromatic hydrocarbons (PAHs) derived from tobacco smoke. Two coding-region mEH variants (Tyr113His, His139Arg) and CYP2C9 variants (Arg144Cys, Ile359Leu) have been described and affect enzyme specific activity. We investigated these polymorphisms and tested interactions with smoking in relationship to risk of colorectal carcinoma in two case-control studies nested in the Nurses' Health Study (NHS) and Physicians' Health Study (PHS) cohorts. mEH Tyr113His and His139Arg polymorphisms were not associated with the risk of cancer among 197 incident cases and 490 controls from the NHS. Among 273 incident cases and 453 controls from the PHS, carrying one or two copies of the 'rapid' 139Arg allele was associated with a significantly reduced risk of colorectal cancer (OR=0.70, 95% CI 0.49--0.99) when compared with His139 wild-type individuals. Risk of colorectal cancer was significantly reduced among men carrying the CYP2C9 *1/*2 genotype (OR=0.62, 95% CI 0.42--0.92) or at least one CYP2C9 variant allele (OR=0.72, 95% CI 0.52--1.00) when compared with *1/*1 wild-type individuals. For women, carrying at least one variant CYP2C9 allele was inversely associated with the risk of colorectal cancer (OR=0.85, 95% CI, 0.57--1.27) when compared with *1/*1 wild-type individuals. No statistically significant genotype-smoking or gene-gene interactions were found in this study. Our results indicate that individuals exposed to tobacco carcinogens were at increased risk of colorectal cancer and that overall risk is related to mEH and CYP2C9 genotype, although the results were not consistent between men and women.     

Pesticide use and colorectal cancer risk in the Agricultural Health Study

We investigated the relationship between agricultural pesticides and colorectal cancer incidence in the Agricultural Health Study. A total of 56,813 pesticide applicators with no prior history of colorectal cancer were included in this analysis. Detailed pesticide exposure and other information were obtained from self-administered questionnaires completed at the time of enrollment (1993-1997). Cancer incidence was determined through population-based cancer registries from enrollment through December 31, 2002. A total of 305 incident colorectal cancers (212 colon, 93 rectum) were diagnosed during the study period, 1993-2002. Although most of the 50 pesticides studied were not associated with colorectal cancer risk, chlorpyrifos use showed significant exposure response trend (p for trend = 0.008) for rectal cancer, rising to a 2.7-fold (95% confidence interval: 1.2-6.4) increased risk in the highest exposure category. Aldicarb was associated with a significantly increased risk of colon cancer (p for trend = 0.001), based on a small number of exposed cases, with the highest exposure category resulting in a 4.1-fold increased risk (95% confidence interval: 1.3-12.8). In contrast, dichlorophenoxyacetic acid showed a significant inverse association with colon cancer but the association was not monotonic. Our findings should be interpreted cautiously since the literature suggesting that pesticides are related to colorectal cancer is limited. Nonetheless the possibility of an association between exposure to certain pesticides and incidence of colorectal cancer among pesticide applicators deserves further evaluation.     

Smoking and the risk of endometrial cancer: results from the Nurses' Health Study

An inverse association between smoking and endometrial cancer has generally been observed, primarily among current smokers. To assess this association, we analyzed data from the prospective Nurses' Health Study. From 1976 to 2000, 702 cases of invasive endometrial cancer were identified during 1.8 million person-years of follow-up. Smoking status was assessed in 1976 and updated every 2 years. Cox proportional hazards models were used to calculate multivariate relative risks (RRs), controlling for endometrial cancer risk factors. Compared to never smokers, the multivariate RR of endometrial cancer was significantly lower among both current smokers (RR = 0.63; 95% CI = 0.50-0.79) and past smokers (RR = 0.73; 95% CI = 0.62-0.87). When additionally adjusting for body mass index (BMI), the RR for current smokers was attenuated (RR = 0.72; 95% CI = 0.57-0.90), but the RR for past smokers did not change. Risk was lower among women who smoked 35 or more cigarettes a day (RR = 0.60; 95% CI = 0.39-0.91) and among those who smoked for 40 or more years (RR = 0.63; 95% CI = 0.45-0.87). Tests for trend, which excluded never smokers, were not statistically significant for any of the smoking variables analyzed. These data indicate that both current and past smoking are associated with a lower risk of endometrial cancer. The findings provide insight into disease etiology and suggest that the influence of smoking on endometrial cancer risk occurs even in early adulthood, is long-lasting, and may not be attributed solely to short-term hormonal modulation.     

Personality,health behaviors,and quality of life among colorectal cancer survivors: Results from the PROFILES registry

Purpose: There is a paucity of research looking into the relationship between personality and health behaviors among cancer survivors. The aim of this study was to investigate whether Type D personality and its two constituent components, negative affectivity (NA) and social inhibition (SI), are associated with health behaviors, quality of life (QoL), and mental distress among colorectal cancer (CRC) survivors. Methods: A population-based study was conducted among 2,620 CRC patients diagnosed between 2000 and 2009, who completed measures of personality (DS14), health behaviors, QoL (EORTC QLQ-C30), and mental distress (hospital anxiety and depression scale). Results: Personality was not associated with body mass index or smoking. Those scoring high on NA (with or without SI) were more often nondrinkers and less physically active compared to those scoring high on neither or only SI. Personality (high scores NA) and health behaviors (inactivity) were independently associated with poor QoL and mental distress. Conclusions: CRC survivors with high scores on NA are at risk of being inactive and have worse health outcomes.     

Vitamin B2 intake and colorectal cancer risk; results from the Nurses' Health Study and the Health Professionals Follow‐Up Study cohort

Vitamin B2 serves as a cofactor to enhance one‐carbon metabolism, maintain mucous membranes, and has been implicated in lowering colorectal cancer (CRC) risk. However, few prospective studies have examined the association between vitamin B2 intake and CRC. In this study, we estimated the associations between vitamin B2 intake and CRC risk using the Nurses' Health Study (NHS) and the Health Professionals Follow‐Up Study (HPFS) cohorts. Vitamin B2 intake was measured by a validated food frequency questionnaire every 4 years. Among 100,033 women in the NHS and 44,007 men in the HPFS we documented a total of 3,037 incident CRC cases (2,093 women and 944 men) during 24–26 years of follow‐up until 2010. Intakes of total (from food and supplements), dietary (from food only), and supplemental vitamin B2 were inversely related to CRC risk in age‐adjusted analysis in NHS. However, the association was attenuated and no longer statistically significant in multivariate analysis (p‐trend ≥0.08). The pooled multivariate relative risks (95% confidence interval) comparing individuals in the extreme quintiles of intakes were 0.93 (0.81–1.06) for total vitamin B2, 0.89 (0.61–1.28) for dietary vitamin B2 and 0.94 (0.81–1.08) for supplemental vitamin B2. These associations of total vitamin B2 intake were similar for risk of CRC with varying lag‐time periods (0–4, 4–8, 8–12 or 12–16 years), for risk of CRC subtypes by tumor location, and across strata of intake of folate or alcohol. Our prospective data do not support a beneficial role of vitamin B2 intake in lowering incidence of CRC.     

Dietary intake of calcium, fiber and other micronutrients in relation to colorectal cancer risk: Results from the Shanghai Women's Health Study

We evaluated the associations of dietary intake of calcium, fiber and vitamins with colorectal cancer risk in a population-based prospective cohort study conducted among Chinese women in Shanghai. Subjects were recruited in urban Shanghai from March 1997 to May 2000. All subjects were interviewed in-person to obtain information on demographic and lifestyle factors and anthropometric measurement was conducted. Usual dietary intake, using a validated food frequency questionnaire was assessed at the baseline survey. After following a total of 73,314 women for a median of 5.74 years, 283 incident colorectal cancer cases were recorded. Excluding the first 2 years of follow-up, a high intake of calcium was associated with a decreased risk of colorectal cancer. Comparing the highest quintile of nutrients intake to the lowest, the adjusted relative risk for colorectal cancer was 0.6 (p value for trend = 0.023) for calcium. No apparent associations were found for fiber, total vitamin A, carotene, vitamins B1, B2, B3, C and E with colorectal cancer risk. Our results suggest that calcium may be protective against colorectal cancer development even at a lower consumption level compared to Western populations.     

口腔健康状况与食管鳞癌发病风险的研究进展

食管癌（esophageal cancer,EC）是世界上最常见的恶性肿瘤之一,进展迅速及预后不良。食管鳞状细胞癌(esophageal squamous cell carcinoma,ESCC)约占EC的90％以上,存在明显的地域、性别及年龄等差异。目前大量研究显示口腔卫生不良是ESCC发病的危险因素之一,但是口腔卫生不良与多种因素相关,且混杂因素较多,因此本综述从牙齿缺失、牙周炎及口腔微生态三方面总结这些因素与ESCC之间的关系,为ESCC高危人群筛查、预防提供新靶标。     

Alcohol intake and risk of colorectal cancer: Results from the UK Dietary Cohort Consortium

Background:

Epidemiological studies have suggested that excessive alcohol intake increases colorectal cancer (CRC) risk. However, findings regarding tumour subsites and sex differences have been inconsistent.

Methods:

We investigated the prospective associations between alcohol intake on overall and site- and sex-specific CRC risk. Analyses were conducted on 579 CRC cases and 1996 matched controls nested within the UK Dietary Cohort Consortium using standardised data obtained from food diaries as a main nutritional method and repeated using data from food frequency questionnaire (FFQ).

Results:

Compared with individuals in the lightest category of drinkers (>0–<5 g per day), the multivariable odds ratios of CRC were 1.16 (95% confidence interval (95% CI): 0.88, 1.53) for non-drinkers, 0.91 (95% CI: 0.67, 1.24) for drinkers with 5–<15 g per day, 0.90 (95% CI: 0.65, 1.25) for drinkers with 15–<30 g per day, 1.02 (95% CI: 0.66, 1.58) for drinkers with 30–<45 g per day and 1.19 (95% CI: 0.75, 1.91) for drinkers with ⩾45 g per day. No clear associations were observed between site-specific CRC risk and alcohol intake in either sex. Analyses using FFQ showed similar results.

Conclusion:

We found no significantly increased risk of CRC up to 30 g per day of alcohol intake within the UK Dietary Cohort Consortium.     

Constipation and colorectal cancer risk: the Fukuoka Colorectal Cancer Study

Constipation has been suspected to be linked to colorectal cancer risk, but epidemiological evidence is inconclusive. We described the prevalence of constipation and related lifestyle factors in a community and examined the relation of constipation and other bowel habits to colorectal cancer risk. The prevalence study was based on 833 community controls in the Fukuoka Colorectal Cancer Study, and 212 cases of Dukes' stage A were used in a study on bowel habits and colorectal cancer risk. Bowel habits were assessed by in-person interview. Odds ratio (OR) and 95% confidence interval (CI) of colorectal cancer were estimated with adjustment for dietary and nondietary factors. Constipation was reported by 10.3% of men and 27.7% of women. Individuals with less frequent bowel movements had a lower intake of total energy and were physically less active. The multivariate-adjusted OR (95% CI) of colorectal cancer were 1.51 (1.02-2.25) for self-reported constipation, 1.60 (1.05-2.44) for functional constipation, and 1.24 (0.81-1.90) for infrequent bowel movements (<1 stool/day). Self-reported constipation was fairly common in Japanese adults. Constipation was associated with a moderately increased risk of colorectal cancer.     

Capecitabine in the management of colorectal cancer

Significant progress has been made in the chemotherapy of colorectal cancer. The author discusses new available options and the development of a new oral fluoropyrimidine, capecitabine (Xeloda?). The rational development of this targeted drug with its selective activation in tumor tissue is highlighted. The clinical development of capecitabine and its present and future role in the management of colorectal cancer are reviewed.     

A prospective study of oral contraceptive use and risk of breast cancer (Nurses' Health Study, United States)

Results of previous epidemiologic studies have provided reassurance that there is little, if any, increase in risk of breast cancer with oral contraceptive (OC) use in general. However, in several studies, an increased risk of breast cancer has been observed in two subgroups, young women who used OCs for extended durations and in women who used OCs prior to a first-term pregnancy. We evaluated these relationships using data from the ongoing Nurses' Health Study cohort (United States). We documented 3,383 cases of breast cancer from 1976 to 1992 among 1.6 million person-years of follow-up. We observed no overall relationship between duration of OC use and breast cancer risk, even among women who reported using OCs for 10 or more years (multivariate relative risk [RR]=1.11, 95 percent confidence interval [CI]=0.94-1.32). Among women less than 45 years of age, the multivariate RR for using OCs for 10 or more years was 1.07 (CI=0.70-1.65) compared with never-users. The risk associated with five or more years of OC use prior to a first full-term pregnancy compared with never-use was 0.96 (CI=0.65-1.43). Among women less than 45 years of age, we observed no evidence of an increased risk with OC use before a first full-term pregnancy (use for five or more years: RR=0.57, CI=0.24-1.31). Because of the age distribution of our cohort, we were unable to evaluate these relationships among women less than 40 years of age. Our study provides considerable evidence that long-term past OC use, either overall or prior to a first full-term pregnancy, does not result in any appreciable increase in breast cancer risk in women over 40 years of age.     

Plasma vitamin D and risk of colorectal cancer: the Japan Public Health Center-Based Prospective Study

We investigated the association between plasma 25(OH)D and the subsequent colorectal cancer incidence risk by a nested case-control study in The Japan Public Health Center-based Prospective Study, covering 375 newly diagnosed cases of colorectal cancer from 38 373 study subjects during a 11.5-year follow-up after blood collection. Two controls were matched per case on sex, age, study area, date of blood draw, and fasting time. In a conditional logistic regression model with matched pairs adjusted for smoking, alcohol consumption, body mass index, physical exercise, vitamin supplement use, and family history of colorectal cancer, plasma 25(OH)D was not significantly associated with colorectal cancer in men or in women. However, the lowest category of plasma 25(OH)D was associated with an elevated risk of rectal cancer in both men (odds ratio (OR), 4.6; 95% confidence interval (CI), 1.0-20) and women (OR, 2.7, 95% CI, 0.94-7.6), compared with the combined category of the other quartiles. Our results suggest that a low level of plasma 25(OH)D may increase the risk of rectal cancer.     

Body mass index and risk of colorectal cancer in Chinese Singaporeans: the Singapore Chinese Health Study

BACKGROUND:

The authors chose to examine the association between body mass index (BMI) and incident colorectal cancer across the spectrum of BMI, including underweight persons, because detailed prospective cohort data on this topic in Asians is scarce, as is data on underweight persons (BMI, <18.5 kg/m²) in any population.

METHODS:

Analysis of the Singapore Chinese Health Study included 51,251 men and women aged 45‐74 years enrolled in 1993‐1998 and followed through 2007. Incident cancer cases and deaths among cohort members were identified through record linkage, and 980 cases were identified. Cox regression models were used to investigate the association of baseline BMI with risk of incident colorectal cancer during a mean of 11.5 years of follow‐up.

RESULTS:

A significant, U‐shaped, quadratic association was observed between BMI and colon cancer risk, with increased risk in BMIs ≥27.5 and <18.5 kg/m². The association was more pronounced in never smokers and most prominent when further limiting the sample to those free of diabetes and cases with longer than 5 years of follow‐up. Localized cases had a more pronounced association in BMIs ≥27.5, whereas advanced cases had a more pronounced association in BMIs <18.5 kg/m². No association was found in relation to rectal cancer risk. The association was also stronger among patients aged 65 years and older.

CONCLUSIONS:

BMI displays a U‐shaped, quadratic association with colon cancer risk in this Chinese population in Southeast Asia. Cancer 2011;. © 2011 American Cancer Society.     

Periodontal disease and risk of non‐Hodgkin lymphoma in the Health Professionals Follow‐Up Study

Periodontal disease is a chronic inflammatory condition that has been associated with chronic diseases, including cancer. In an earlier prospective cohort analysis within the Health Professionals Follow‐Up Study (HPFS), we observed a 31% higher risk of non‐Hodgkin lymphoma (NHL) among participants with severe periodontal disease at baseline. Here, we extend the study with an additional 8 years of follow‐up, and conduct analyses with updated periodontal disease status and NHL subtypes. The HPFS is an ongoing prospective cohort study of 51,529 men in the USA Between baseline in 1986 and 2012, 875 cases of NHL were diagnosed, including 290 chronic lymphocytic leukemia/small lymphocytic lymphomas (CLL/SLL), 85 diffuse large B‐cell lymphomas and 91 follicular lymphomas. We performed multivariable Cox proportional hazards regression to evaluate associations of interest. History of periodontal disease at baseline was positively associated with risk of NHL overall (hazard ratio (HR) = 1.26, 95% confidence interval (CI): 1.06–1.49) and CLL/SLL (HR = 1.41, 95% CI: 1.04–1.90). With updated periodontal status, HRs were 1.30 (95% CI: 1.11–1.51) for NHL overall and 1.41 (95% CI: 1.08–1.84) for CLL/SLL. In contrast, after adjusting for periodontal disease, tooth loss was inversely associated with NHL, suggesting that other causes or consequences of tooth loss may have different implications for NHL etiology. Our findings suggest that periodontal disease is a risk factor for NHL. Whether periodontal disease is a direct or indirect cause of NHL, or is a marker of underlying systemic inflammation and/or immune dysregulation, warrants further investigation.