The relationship between diet and breast cancer in men (United States)

Glucosinolate and isothiocyanate intakes are inversely associated with breast cancer risk: a case–control study in China

Although previous studies have investigated the association of cruciferous vegetable consumption with breast cancer risk, few studies focused on the association between bioactive components in cruciferous vegetables, glucosinolates (GSL) and isothiocyanates (ITC), and breast cancer risk. This study aimed to examine the association between consumption of cruciferous vegetables and breast cancer risk according to GSL and ITC contents in a Chinese population. A total of 1485 cases and 1506 controls were recruited into this case–control study from June 2007 to March 2017. Consumption of cruciferous vegetables was assessed using a validated FFQ. Dietary GSL and ITC were computed by using two food composition databases linking GSL and ITC contents in cruciferous vegetables with responses to the FFQ. The OR and 95 % CI were assessed by unconditional logistic regression after adjusting for the potential confounders. Significant inverse associations were found between consumption of cruciferous vegetables, GSL and ITC and breast cancer risk. The adjusted OR comparing the highest with the lowest quartile were 0·51 (95 % CI 0·41, 0·63) for cruciferous vegetables, 0·54 (95 % CI 0·44, 0·67) for GSL and 0·62 (95 % CI 0·50, 0·76) for ITC, respectively. These inverse associations were also observed in both premenopausal and postmenopausal women. Subgroup analysis by hormone receptor status found inverse associations between cruciferous vegetables, GSL and ITC and both hormone-receptor-positive or hormone-receptor-negative breast cancer. This study indicated that consumption of cruciferous vegetables, GSL and ITC was inversely associated with breast cancer risk among Chinese women.

Association between dietary nitrate and nitrite intake and sitespecific cancer risk: evidence from observational studies

Epidemiological studies have reported inconsistent findings on the association between dietary nitrate and nitrite intake and cancer risk. We performed a meta-analysis of epidemiological studies to summarize available evidence on the association between dietary nitrate and nitrite intake and cancer risk from published prospective and case-control studies. PubMed database was searched to identify eligible publications through April 30^th, 2016. Study-specific relative risks (RRs) with corresponding 95% confidence interval (CI) from individual studies were pooled by using random- or fixed- model, and heterogeneity and publication bias analyses were conducted.

Data from 62 observational studies, 49 studies for nitrates and 51 studies for nitrites, including a total of 60,627 cancer cases were analyzed. Comparing the highest vs. lowest levels, dietary nitrate intake was inversely associated with gastric cancer risk (RR = 0.78; 95%CI = 0.67-0.91) with moderate heterogeneity (I² = 42.3%). In contrast, dietary nitrite intake was positively associated with adult glioma and thyroid cancer risk with pooled RR of 1.21 (95%CI = 1.03-1.42) and 1.52 (95%CI = 1.12-2.05), respectively. No significant associations were found between dietary nitrate/nitrite and cancers of the breast, bladder, colorectal, esophagus, renal cell, non-Hodgkin lymphoma, ovarian, and pancreas. The present meta-analysis provided modest evidence that positive associations of dietary nitrate and negative associations of dietary nitrite with certain cancers.

Suppressive Effects of Tea Catechins on Breast Cancer

Tea leaf (Camellia sinensis) is rich in catechins, which endow tea with various health benefits. There are more than ten catechin compounds in tea, among which epigallocatechingallate (EGCG) is the most abundant. Epidemiological studies on the association between tea consumption and the risk of breast cancer were summarized, and the inhibitory effects of tea catechins on breast cancer, with EGCG as a representative compound, were reviewed in the present paper. The controversial results regarding the role of tea in breast cancer and areas for further study were discussed.

Tobacco and alcohol in relation to male breast cancer: an analysis of the male breast cancer pooling project consortium

BACKGROUND

The etiology of male breast cancer is poorly understood, partly due to its relative rarity. Although tobacco and alcohol exposures are known carcinogens, their association with male breast cancer risk remains ill-defined.

METHODS

The Male Breast Cancer Pooling Project consortium provided 2,378 cases and 51,959 controls for analysis from 10 case-control and 10 cohort studies. Individual participant data were harmonized and pooled. Unconditional logistic regression was used to estimate study design-specific (case-control/cohort) ORs and 95% confidence intervals (CI), which were then combined using fixed-effects meta-analysis.

RESULTS

Cigarette smoking status, smoking pack-years, duration, intensity, and age at initiation were not associated with male breast cancer risk. Relations with cigar and pipe smoking, tobacco chewing, and snuff use were also null. Recent alcohol consumption and average grams of alcohol consumed per day were also not associated with risk; only one subanalysis of very high recent alcohol consumption (>60 g/day) was tentatively associated with male breast cancer (ORunexposed referent = 1.29; 95% CI, 0.97-1.71; OR>0-<7 g/day referent = 1.36; 95% CI, 1.04-1.77). Specific alcoholic beverage types were not associated with male breast cancer. Relations were not altered when stratified by age or body mass index.

CONCLUSIONS

In this analysis of the Male Breast Cancer Pooling Project, we found little evidence that tobacco and alcohol exposures were associated with risk of male breast cancer.

IMPACT

Tobacco and alcohol do not appear to be carcinogenic for male breast cancer. Future studies should aim to assess these exposures in relation to subtypes of male breast cancer.

Male breast cancer: risk factors, biology, diagnosis, treatment, and survivorship

BACKGROUND

The causes, optimal treatments, and medical/psychosocial sequelae of breast cancer in men are poorly understood.

DESIGN

A systematic review of the English language literature was conducted to identify studies relevant to male breast cancer between 1987 and 2012 and including at least 20 patients. Searches were carried out on PubMed using the title terms 'male breast cancer' or 'male breast carcinoma'.

RESULTS

Relevant published data regarding risk factors, biological characteristics, presentation and prognosis, appropriate evaluation and treatment, and survivorship issues in male breast cancer patients are presented. BRCA2 mutations, age, conditions that alter the estrogen/androgen ratio, and radiation are proven risk factors. Disease biology is distinct in men, but diagnostic approaches and treatments for men are generally extrapolated from those in women due to inadequate research in men. Survivorship issues in men may include sexual and hormonal side-effects of endocrine therapies as well as unique psychosocial impacts of the disease.

CONCLUSION

Further research is needed to address gaps in knowledge pertaining to care of male breast cancer patients and survivors.

Coffee consumption and risk of breast cancer: an up-to-date meta-analysis

Objectives

This updated meta-analysis was conducted to assess the association between coffee consumption and breast cancer risk.

Methods

We conducted a systematic search updated July 2012 to identify observational studies providing quantitative estimates for breast cancer risk in relation to coffee consumption. Pooled relative risks (RRs) with 95% confidence intervals (CIs) were calculated using a random-effects model, and generalized least square trend estimation was used to assess dose–response relationships.

Results

A total of 26 studies (16 cohort and 10 case–control studies) on coffee intake with 49497 breast cancer cases were included in the meta-analysis. The pooled RR showed a borderline significant influence of highest coffee consumption (RR = 0.96; 95% CI 0.93–1.00), low-to moderate coffee consumption (RR = 0.99; 95% CI 0.95–1.04), or an increment of 2 cups/day of coffee consumption (RR = 0.98; 95% CI 0.97–1.00) on the risk of breast cancer. In stratified analysis, a significant inverse association was observed in ER-negative subgroup. However, no significant association was noted in the others.

Conclusions

Our findings suggest that increased coffee intake is not associated with a significantly reduced risk of breast cancer, but we observe an inverse association in ER-negative subgroup analysis. More large studies are needed to determine subgroups to obtain more valuable data on coffee drinking and breast cancer risk.

Perceptions and opinions about male breast cancer and male breast self-examination: a qualitative study

OBJECTIVE

While the relatively common nature of female breast cancer has resulted in a high level of general awareness, male breast cancer is still comparatively unknown to the general public and to healthcare professionals. The objective of this study is to explore the perceptions and opinions about male breast cancer and male breast self-examination among male university students.

METHODOLOGY

In-depth interviews were conducted among 36 male university students from the Management and Science University, Malaysia, selected by simple random sampling. The themes of the interview were: knowledge of male breast cancer and male breast self-examination, sources of knowledge and attitudes towards male BSE. The data obtained were classified into various categories and analyzed manually.

RESULTS

The majority of participants mentioned that there is a low possibility for males to get breast cancer. They also believed that the cause of breast cancer among men is due to the carcinogens from cigarettes. The majority of participants mentioned that they know about breast self-examination from the mass media and that the presence of a lump in the breast is the main symptom of breast cancer in men. The majority of participants mentioned that they encourage their family members to practice breast self-examination but considered that BSE is not important for men because they have a low probability of getting breast cancer.

CONCLUSIONS

Misconceptions regarding male breast cancer and breast self-examination among men still exist among male university students. Therefore special attention should be given to educate men about male breast cancer and male BSE.

Cruciferous vegetables intake is inversely associated with risk of breast cancer: a meta-analysis

PURPOSE

The objective of the study was to examine the associations of cruciferous vegetables intake with risk of breast cancer.

METHODS

Studies were identified by searching PubMed databases and screening the references of retrieved articles and reviews. Summary odds ratios (ORs) for the highest versus lowest cruciferous vegetables consumption levels were calculated using fixed or random effects models depending on heterogeneity between studies. Heterogeneity among studies was examined using Q and I(2) statistics. Publication bias was assessed using the Egger's and Begg's tests.

RESULTS

Thirteen epidemiologic studies (11 case-control and 2 cohort studies) were included in the meta-analysis. The combined results from all studies indicated that high cruciferous vegetables intake was significantly associated with reduced breast cancer risk (RR = 0.85, 95% CI = 0.77-0.94).

CONCLUSION

Findings from this meta-analysis suggest that cruciferous vegetables consumption may reduce the risk of breast cancer. Because of the limited number of studies, further prospective studies are needed to explore the protective effect of cruciferous vegetables on breast cancer.

Clinicopathological study of male breast carcinoma: 24 years of experience

BACKGROUND AND OBJECTIVES

Because breast cancer in men is rare, few patients are available for prospective studies. To learn more about its epidemiology, risk factors, clinical features, genetics and pathology in our country, we conducted a retrospective study of all cases seen in recent decades at our institution.

PATIENTS AND METHODS

We identified each case of male breast cancer in the database at the Sher-i-Kashmir Institute of Medical Sciences, Srinagar, Kashmir, India, between the years 1983 to 2007.

RESULTS

We identified only 32 cases of male breast cancer over the 24-year period. Male breast cancer accounted for 32 (2.8%) of 1141 resected breast specimens, which included all breast lesions and 32 (4.1%) of 780 breast cancer cases. Of the 32 cases, 20 (62.5%) had various associated risk factors. Invasive ductal carcinoma was seen in 30 cases (93.7%). Of 20 cases that underwent molecular studies, 16 (80%) patients had estrogen receptor positivity whereas 14 (70%) had progesterone receptor positivity. Six cases (30%) overexpressed HER2 and p53. The BRCA2 mutation was observed in 4 cases (40%) while no patient presented with the BRCA1 mutation.

CONCLUSION

An incidence of 4.1% for male breast cancer indicates that this disease is not as uncommon as presumed in this part of the world. Breast cancer in men seems more frequently to be hormone receptor positive and the BRCA2 mutation confers a significant risk to men.

Etiologic factors for male breast cancer in the U.S. Veterans Affairs medical care system database

The etiology of male breast cancer is largely unknown, reflecting its relative rarity. Although a number of previous studies have suggested relationships with a variety of medical conditions, the results have largely derived from case-control studies and may reflect recall biases. Within the large U.S. Veterans Affairs computerized medical care system database, we had the opportunity to access 26 million hospital discharge records over the period 1969-1996 and to relate various documented medical conditions to the risk of subsequent male breast cancer. This allowed us to calculate relative risks (RR) and 95% confidence intervals (CI) for male breast cancer associated with conditions occurring one or more years after initial hospitalization, adjusted for age, race, calendar year, duration of follow-up, and number of hospital visits. Among 4,501,578 men aged 18-100 years, a total of 642 cases of primary male breast cancer were identified (523 among whites, 119 among blacks). Medical conditions that were significantly related to risk were diabetes (RR 1.30, 95% CI 1.05-1.60), obesity (1.98, 1.55-2.54), orchitis/epididymitis (1.84, 1.10-3.08), Klinefelter syndrome (29.64, 12.26-71.68), and gynecomastia (5.86, 3.74-9.17). Additionally, among black patients, cholelithiasis emerged as a significant risk predictor (3.45, 1.59-7.47). Diseases that have previously been related to male breast cancer risk that were not supported by our study results included thyroid diseases, smoking-related conditions, liver cirrhosis, prostatic hyperplasia, and fractures. After adjustment for obesity, the association with diabetes disappeared, but that with gynecomastia persisted. In multivariate models that simultaneously considered all important medical predictors of risk, significant risks were seen for Klinefelter syndrome (16.83, 6.81-41.62), gynecomastia (5.08, 3.21-8.03), obesity (1.91, 1.50-2.44), and orchitis/epididymitis (1.80, 1.08-3.01). These results support previous speculations that male breast cancer is influenced not only by tissue at risk, but also by hormonal and inflammatory factors.

Coffee consumption and risk of breast cancer: a metaanalysis

OBJECTIVE

This metaanalysis was conducted to assess the association between coffee consumption and breast cancer risk.

STUDY DESIGN

Relevant studies were identified by searching Medline (1966-May 2008) and the reference lists of retrieved articles. The summary relative risk (RR) with 95% confidence interval (CI) was calculated using a random-effects model.

RESULTS

Nine cohort and 9 case-control studies met the inclusion criteria. The combined RR showed a borderline significant influence of highest coffee consumption (RR, 0.95; 95% CI, 0.90-1.00) or an increment of 2 cups/day of coffee consumption (RR, 0.98; 95% CI, 0.96-1.00) on the risk of breast cancer. In stratified analysis, borderline significant associations were observed among cohort and case-control studies and studies conducted in Europe and the United States. However, no significant association was noted among studies conducted in Asia.

CONCLUSION

Our findings suggest a possible influence of high coffee consumption or an increased coffee consumption on the risk of breast cancer.

A Review of the Diagnosis and Management of Male Breast Cancer

Male breast cancer is an uncommon disease although the incidence has increased over the past 25 years. As with many other rare "orphan" diseases, male breast cancer is understudied. The rarity of the disease precludes prospective randomized clinical trials. In addition, few researchers and minimal funding have focused on breast cancer in men, but further work is clearly needed to better understand this disease. It shares many similarities with breast cancer in women; yet some clear differences have emerged. In this article, the latest information on the epidemiology, biology, and treatment of male breast cancer is reviewed.

Male breast cancer--an andrological disease: risk factors and diagnosis

Gynaecomastia, the enlargement of the male breast, is considered as an andrological disease. To date, a review on male breast cancer (MBC) has not been published in an andrological journal. The papers underlying this review were published from authors of different institutions: Clinical Genetics, Dermatology, Gynaecology, Internal Medicine, Oncology, Pathology, Psychiatry, Radiology and Surgery. MBC accounts for approximately 1% of breast cancer patients. A total of 182 men died of breast cancer in 1999, in Germany. In the US, 1500 new cases per year occur. MBC accounts for <5% of surgically removed breast lumps. Diseases with increased oestrogen action increase the risk of MBC. Mutations of distinct genes are estimated to account for up to roughly 10% of MBC. BRCA1 and BRCA2 gene mutations are responsible for approximately 80% of the families with hereditary breast cancer. The diagnosis of MBC is not possible without histological examination. Different diagnostic procedures such as clinical diagnosis, sonography, mammography, fine-needle biopsy and core needle facilitate the decision whether a biopsy is necessary.

Risk factors for male breast cancer in Canada, 1994-1998

Relatively little attention has been paid to the aetiology of male breast cancer and the current understanding of female breast cancer, primarily related to reproductive events, cannot be readily transferred to understanding the cancer in males. However, since male breast cancer occurs in the absence of factors related to childbearing and menstruation, its aetiology may provide special insights into the causes of breast cancer in women. We examined lifestyle risk factors for male breast cancer as part of a Canadian, multi-site, population-based, case-control study. Eighty-one newly diagnosed, histologically confirmed cases and 1905 male controls aged 42-74 were analysed using unconditional logistic regression. Increased risks were found for men with a mother or sister with breast cancer (adjusted odds ratio (OR) 3.65, 95% confidence interval (95% CI) 1.62-8.19). Higher physical activity levels (moderate, and strenuous recreational plus occupational) were associated with a decreased risk of male breast cancer (highest quartile, adjusted OR 0.48, 95% CI 0.26-0.91). Similarly, higher risks were associated with higher weight 2 years before interview (2.19, 95% CI 1.08-4.43), maximum weight (OR 2.66) and higher body mass index (OR 1.60). Higher vegetable consumption and coffee consumption were associated with decreased risk, whereas higher beta-carotene, vitamin E and calcium supplementation were associated with statistically significant increased risk. The small number of cases and multiple comparisons preclude strong conclusions, but our study is consistent with studies suggesting obesity and family history increase risk, and physical activity decreases risk of breast cancer.

Prevalence of BRCA1 and BRCA2 mutations in male breast cancer patients in Canada

Men who inherit a mutation in the BRCA2 gene carry a 6% risk of developing breast cancer by the age of 70. The proportion of male breast cancers attributable to BRCA mutations has not yet been determined with accuracy. We studied a series of 14 male breast cancer patients, unselected for family history or ethnicity, who were treated at a single regional cancer center in Canada. Family histories were obtained, and the men were tested for germ-line mutations of BRCA1 and BRCA2. Seven of these patients had a significant family history of breast cancer (i.e., at least one first- or second-degree relative with breast cancer diagnosed before age 70). Two of the men carried BRCA2 mutations, but no BRCA1 mutations were found. Both mutation carriers reported a positive family history and a personal history of cancer that preceded their diagnosis of breast cancer. Our results support the recommendation that male breast cancer patients who have a significant family history of breast or ovarian cancer should be offered genetic counseling and testing.

Epidemiology, prevention, and early detection of breast cancer

Globally, breast cancer is the third most common form of cancer and the most common among women. The age-adjusted incidence rates of breast cancer are 176% higher in developed than in developing nations. Male breast cancer is rare, but important studies provided risk factor information for comparison with studies of female breast cancer. There has been considerable interest in a possible role of organochlorines and polychlorinated biphenyls in the etiology of breast cancer, but the results of several null studies indicate the likelihood of such associations is extremely remote, providing reassuring news for the public. Prophylactic mastectomy was observed to significantly reduce a woman's chances of developing breast cancer, but it does not lower the risk to zero. Tamoxifen was found to be an effective chemopreventive agent in the Breast Cancer Prevention Trial, but this result was not replicated in two randomized trials in Europe. Striking reductions in the risk for breast cancer were observed for raloxifene in a randomized, placebo-controlled trial that had been designed for the prevention of osteoporosis. A large-scale, randomized trial of tamoxifen-verus-raloxifene among women at increased risk for developing breast cancer is now underway.