Risk factors predicting the incidence of second primary breast cancer among women diagnosed with a first primary breast cancer.

This study examined risk factors for development of a contralateral breast cancer among 4,660 US women diagnosed with a first primary breast cancer between 1980 and 1982. The authors believe it to be the first prospective cohort study on this topic that has employed direct patient interviews. All subjects were interviewed within 6 months of the diagnosis of their initial tumor as part of the multi-center, population-based, case-control Cancer and Steroid Hormone Study, and they were followed until the end of 1986 through the Surveillance, Epidemiology, and End Results program. Exclusive of those diagnosed during the initial 6 months after diagnosis of a first primary, 136 second primary breast cancers were identified. Proportional hazards models were used to assess the independent effects of multiple predictors. Specific risk factors evaluated included: age at diagnosis of first primary, exposure to exogenous hormones, menstrual and reproductive histories, tumor characteristics, demographic variables, and treatment modalities. The age-specific incidence rates of second primary breast cancer were higher in all age categories than are the incidence rates of breast cancer in the general population, yet the age at diagnosis of first primary breast cancer was not an important predictor of contralateral breast cancer. The risk of contralateral breast cancer was increased among cohort members who reported a personal history of benign breast biopsy (multivariable-adjusted rate ratio (RR) = 1.69, 95% confidence interval (CI) 1.13-2.53) and in those with an initial tumor that was classified as lobular carcinoma (multivariable-adjusted RR = 1.96, 95% CI 1.17-3.27). Treatment with chemotherapy for the first primary was associated with a lower risk of development of a second breast cancer (multivariable-adjusted RR = 0.56, 95% CI 0.33-0.96), while radiation therapy had little effect on the risk (multivariable-adjusted RR = 1.19, 95% CI 0.78-1.80).     

Association of parity and ovarian cancer risk by family history of breast or ovarian cancer in a population-based study of postmenopausal women.

Although parity is associated with a decreased risk of ovarian cancer in the general population, this association among women with a family history is less clear. We examined this question in a prospective cohort of 31,377 Iowa women 55-69 years of age at baseline. Relative risks (RRs) and 95% confidence intervals (CIs) were estimated through Cox regression. We identified 181 incident epithelial ovarian cancers through 13 years of follow-up. At baseline, 14% of the women reported breast or ovarian cancer in a first-degree relative, and an additional 12% reported a family history in a second-degree relative. Among women without a family history of breast or ovarian cancer in a first-degree relative, nulliparous women were at slightly increased risk of ovarian cancer (RR = 1.4, 95% CI = 0.9-2.4) compared with parous women, whereas among women with a family history, nulliparous women were at a much higher risk (RR = 2.7, 95% CI = 1.1-6.6) than parous women. Similar results were seen when family history included first- or second-degree relatives with breast or ovarian cancer or a first- or second-degree relative with ovarian cancer only. Nulliparity may be more strongly associated with an increased risk of ovarian cancer among women with a family history of breast or ovarian cancer, compared with women who do not have a family history of those cancers.     

Family history of reproductive cancers and ovarian cancer risk: an Italian case-control study.

The relation between family history of ovarian, breast, and endometrial cancer and risk of epithelial ovarian carcinoma was analyzed within the framework of a case-control study conducted from 1983 to 1989. The study included 755 cases of ovarian cancer and 2,023 controls in hospital for a spectrum of acute nongynecologic, hormonal, or neoplastic conditions in the Greater Milan area, Italy. Eighteen cases (2%) and 24 controls (1%) reported a history of ovarian cancer in a first-degree relative: The corresponding multivariate adjusted odds ratio (OR) was 1.9 (95% confidence interval (CI) 1.1-3.6). The risk of ovarian cancer was elevated in women reporting a family history of breast cancer (OR = 1.6, 95% CI 1.1-2.3), but no significant association emerged with a family history of endometrial cancer (OR = 1.3, 95% CI 0.8-1.7). When the data were stratified by family history of breast cancer, a family history of ovarian cancer was over 10 times more frequent in both cases and controls who reported a family history of breast cancer than in cases and controls reporting no family history of breast cancer. The estimated odds ratio for ovarian cancer associated with a family history of the disease was 2.3 (95% CI 1.1-4.5) in women not reporting a family history of breast cancer, but no association emerged in the subgroup of women reporting a family history of breast cancer. These results confirm that a family history of ovarian cancer increases the risk of the disease, but the percentage of ovarian cancer cases explained by a family history of the disease is small: Less than 1% of observed cases in this study could be attributed to this "family risk factor."     

Relationship of epithelial ovarian cancer to other malignancies within families

The relationship of family history of cancer of the breast, colon/rectum, cervix, endometrium, lung, and thyroid to the risk of epithelial ovarian cancer was investigated in a large population-based case-control study. The data consisted of family histories from 493 epithelial ovarian cancer cases and 2,465 controls aged 20-54 years. After controlling for potential confounders, risk for epithelial ovarian cancer was found to be significantly elevated among women reporting breast cancer and colo/rectal cancer in a first-degree relative. Adjusted odds ratios were 1.5 (95% CI = 1.1-2.1) and 1.9 (95% CI = 1.1-3.3), respectively. None of the remaining four types of cancer was found to be statistically associated with the risk of epithelial ovarian cancer. However, when histologic subtypes of epithelial ovarian cancer were considered, a family history of breast cancer was found to be associated with an elevated risk of endometrioid ovarian cancer (odds ratio = 2.3; 95% CI = 1.1-4.7), as was a family history of endometrial cancer (odds ratio = 2.7; 95% CI = 1.0-6.9). The results are considered in the context of other studies of familial patterns of cancer and are compared with published findings concerning the occurrence of multiple primary cancers in the same individual. The findings indicate that further study is warranted regarding possible genetic relationships between epithelial ovarian cancer and cancers arising in other organs.     

Psychotropic medication use and risk of hormone-related cancers: the New York University Women's Health Study

BACKGROUND: The use of psychotropic medications may increase the risk of hormone-related cancers in females through increased gonadotropin secretion, but the data from epidemiologic studies are limited to evaluate the hypothesis. METHODS: The association between the use of psychotropic medications and cancer incidence was studied in a prospective cohort study that involves 15,270 women who participated in mammographic screening. The relative risks (RR) and 95 per cent confidence intervals (CIs) for cancer associated with the use of psychotropic medications were estimated by the Cox's proportional hazard model. RESULTS: During an average of 7.3 years of follow-up, 1,130 incident cases of cancer were identified, including 566 breast, 67 endometrial and 47 ovarian cancers. The use of any type of psychotropic medication at baseline was associated with increased risks of breast [relative risk (RR) = 1.39, 95 per cent CI 1.11-1.74], endometrial (RR=1.71; 95 per cent CI 0.93-3.14) and ovarian (RR= 1.48, 95 per cent CI 0.69-3.16) cancers, whereas no increase in risk was observed for other cancers (RR = 1.06). When the subjects were divided by menopausal status at baseline, premenopausal women tended to have higher risk of all hormone-related cancers (RR = 1.73, 95 per cent CI 1.27-2.35) than postmenopausal women (RR=1.23, 95 per cent CI 0.94-1.62). The magnitude of the RR associated with the use of these medications did not change by length of follow-up. Analysis by type of medication did not find that the association was limited to specific types. CONCLUSION: The observed association needs to be confirmed in further studies based on more detailed medication history.     

Aggregation of ovarian cancer with breast, ovarian, colorectal, and prostate cancer in first-degree relatives

Epidemiologic studies have demonstrated a tendency for common cancers to aggregate in families. The authors investigated the effects of family history of cancer at multiple sites, including the breast, ovary, colorectum, and prostate, on ovarian cancer risk among 607 controls and 558 ovarian cases in Hawaii and Los Angeles, California, in 1993-1999. A family history of cancer of the breast, ovary, colorectum, or prostate in first-degree relatives was associated with an increased risk of ovarian cancer (odds ratio (OR)=1.7, 95% confidence interval (CI): 1.1, 2.6; OR=3.2, 95% CI: 1.3, 7.9; OR=1.5, 95% CI: 0.9, 2.5; and OR=1.6, 95% CI: 1.0, 2.8, respectively). A greater risk of ovarian cancer was observed for women with parents rather than siblings with a history of breast or prostate cancer and for women with parental colorectal cancer diagnosed at an early age, suggesting a genetic predisposition among these women. The risk of nonmucinous tumors, but not mucinous tumors, was positively associated with a family history of cancer. No significant interaction effects on risk existed between oral contraceptive pill use or pregnancy and family history of breast and/or ovarian cancer. Study findings suggest that ovarian cancer aggregates with several common cancers in family members.     

Risk of contralateral breast cancer: associations with factors related to initial breast cancer

A case-control study was conducted to assess the risk factors associated with the development of a contralateral primary breast cancer among women who had had a first primary breast cancer. Hospital records were reviewed for 292 women who had an incident contralateral breast cancer, diagnosed in one of eight Connecticut hospitals between July 1, 1975 and December 31, 1983, and for a comparison group of 264 surviving unilateral breast cancer patients previously diagnosed in the same hospitals. All subjects were identified through the records of the Connecticut Tumor Registry. A family history of breast cancer in any first- or second-degree relative was associated with an almost threefold increased risk of developing a contralateral cancer (adjusted odds ratio (OR) = 2.8, 95% confidence interval (CI) = 1.6-4.9). Further, this relation was modified by the time elapsed since the initial cancer diagnosis (ratio of OR = 1.9, 95% CI = 1.2-3.0 for a five-year differential in time since initial diagnosis). A delay of 10 years in first full-term pregnancy was associated with a 36% decrease in risk (adjusted OR = 0.6, 95% CI = 0.3-1.2); this estimate excluded the magnitude of increased risk usually observed in studies of initial breast cancer. A conceptual framework is presented for assessing the study findings in the context of previous studies that have examined the corresponding associations for initial primary breast cancers.     

Breast cancer incidence in women with abnormal cytology in nipple aspirates of breast fluid.

This is a prospective study of breast cancer risk in relation to nipple aspirate fluid cytology in 2,701 volunteer white women from the San Francisco Bay Area first enrolled between 1973 and 1980. The women were not pregnant or lactating and were free of breast cancer within 6 months of entry into the study. The breast cancer status of this cohort was determined between June 1988 and April 1991. Follow-up was complete for 87% (n = 2,343) of the cohort, representing 29,961 person-years and an average of 12.7 years of follow-up. The overall breast cancer incidence was 4.4% (104 of 2,343) and rose with fluid cytology findings as follows: no fluid obtained, 2.6% (9 of 352); unsatisfactory specimen, 4.8% (15 of 315); normal cytology, 4.3% (56 of 1,291); epithelial hyperplasia, 5.5% (18 of 327); and atypical hyperplasia, 10.3% (6 of 58). Relative risks for breast cancer and their 95% confidence intervals were estimated by Cox regression, adjusting for age and year of entry. Compared with the relative risk for women who yielded no fluid, relative risks were: unsatisfactory specimen, relative risk (RR) = 1.4 (95% confidence interval (CI) 0.6-3.3); normal cytology, RR = 1.8 (95% CI 0.9-3.6); epithelial hyperplasia, RR = 2.5 (95% CI 1.1-5.5); and atypical hyperplasia, RR = 4.9 (95% CI 1.7-13.9). These findings were strongest for and were mainly confined to women aged 25-54 years. Women with atypical hyperplasia and a first-degree family history of breast cancer were six times more likely to develop breast cancer than were women with atypical hyperplasia but without a family history of breast cancer (95% CI 1.0-30.2). These findings provide strong support for our hypothesis that hyperplasia and atypical hyperplasia diagnosed in nipple aspirates of breast fluid are associated with an increased risk of breast cancer.     

Fracture history and risk of breast and endometrial cancer

Fractures in postmenopausal women may serve as a surrogate measure of bone density, reflecting long-term lower estrogen levels, and lower estrogen levels appear to be inversely associated with breast and endometrial cancer. Breast cancer cases aged 50-79 years (n = 5,559) and endometrial cancer cases aged 40-79 years (n = 739) were enrolled in a US case-control study in 1992-1994 to evaluate the relation between fractures and risk of breast and endometrial cancer. Controls for the breast cancer analysis (n = 5,829) and the endometrial cancer analysis (n = 2,334) were randomly selected from population lists (driver's license and Medicare files). Information on fracture history and other risk factors was obtained by telephone interview. Compared with women without a fracture in the past 5 years, the odds ratios for women with a history of fracture were 0.80 (95% confidence interval (CI): 0.68, 0.94) for breast cancer and 0.59 (95% CI: 0.40, 0.89) for endometrial cancer. Height loss (> or =2.5 cm) and recent fracture history were associated with the lowest risk of breast cancer (odds ratio = 0.62, 95% CI: 0.46, 0.83) and endometrial cancer (odds ratio = 0.15, 95% CI: 0.05, 0.43). These data suggest that the endogenous hormonal factors associated with increased fracture risk are also related to decreased breast cancer risk and, more strongly, to endometrial cancer risk.     

Second primary ovarian cancer among women with cancer

PURPOSE: Some studies suggest women with certain types of cancers are at increased risk for ovarian cancer. This study assessed the risk of second primary ovarian cancer among U.S. women who have cancer by anatomic site, age, race, and time since diagnosis of the first primary cancer.METHODS: We analyzed data from SEER cancer registries for women diagnosed with invasive cancer between 1973 and 1996. Person-years were accumulated from 2 months after initial cancer diagnosis to date of ovarian cancer diagnosis, death, loss to follow-up, or end of follow-up, December 31, 1996. The expected number of cases was obtained by multiplying 5-year age and calendar year interval specific ovarian cancer rates by the accumulated person-years at risk. We calculated the risk (observed [O]/expected numbers [E]) of second primary ovarian cancer by cancer site and age (<50 years, >/=50 years), race (all, white, black), and time since first cancer (0-4, 5-9, 10-14, 15-24 years). Statistical tests and 95% confidence intervals (CI) were based on the assumption of a Poisson distribution.RESULTS: A significant increased risk of ovarian cancer was found for women aged <50 years at time of diagnosis with melanoma (O/E = 3.5, 95% CI = 2.1-5.5) and cancer of the breast (O/E = 6.0, 95% CI = 4.9-7.2), cervix (O/E = 4.2, 95% CI = 2.6-6.3), corpus uteri (O/E = 11.91, 95% CI = 7.3-18.4), colon (O/E = 17.9, 95% CI = 11.1-27.3), and ovary (O/E = 4.9, 95% CI = 2.7-8.2); no increased risk was found for women aged >/=50 years. Ovarian cancer risk remained elevated following all of these first primary cancers 5-9 years after diagnosis; for women with breast and colon cancer, risk remained elevated 15-24 years after diagnosis. A significant increased risk was found for all of these cancers among white women <50 years at diagnosis; risk was increased among black women <50 years with cancer of the breast, cervix, and colon.CONCLUSIONS: We found an ovarian cancer risk higher than expected for women with certain types of cancer; however, the risk was limited to women <50 years of age.     

The HER2 I655V polymorphism and breast cancer risk in Ashkenazim

SUMMARY: BACKGROUND Over-expression of the human epidermal growth factor receptor 2 (Her2) protooncogene is associated with poor prognosis among female patients with breast cancer. A polymorphism in the HER2 gene (I655V) has been associated with an elevated risk of breast cancer in some ethnic groups.METHODS Subjects from a community-based study of 5318 Ashkenazim from the Washington, DC area were selected for analysis of the I655V HER2 germline polymorphism. We estimated age-specific breast cancer risk from HER2 I655V based on the family history data, using the female first-degree relatives of the study participants and a novel extension of the kin cohort method.RESULTS The estimated cumulative risk of breast cancer to age 70 was approximately 30% higher among HER2 I655V carriers than noncarriers (RR = 1.33; 95% confidence interval [CI] = 1.03-1.83). The effect of the allele seems stronger at younger ages (among women younger than 50 years, RR = 2.11; CI = 1.39-3.28) and especially among younger women with a family history of breast cancer (RR = 8.9; CI = 1.9-19.7). Increased risk of breast cancer associated with the I655V allele was also observed among BRCA1/2 mutation carriers, although these results are based on small numbers.CONCLUSION These analyses suggest that the HER2 valine allele might be associated with increased risk of breast cancer, especially in young women and in women with a family history of the disease.     

Familial clustering of colon,breast, uterine,and ovarian cancers as assessed by family history

The aggregation of colon, endometrial, ovarian, and possibly breast cancers in families has been described as a “cancer family syndrome” (now called Lynch syndrome II). To determine if the familial clustering of these malignancies was more common in women with cancer than without, we analyzed data from the Iowa Women's Health Study (IWHS), a population-based sample of 41,837 women aged 55–69 years. Self-reported information was collected on history of colon, uterine, ovarian, and breast cancers in female first-degree relatives. A family history of cancer of the breast (odds ratio [OR] = 1.4), colon (OR = 1.3), and uterus (OR = 1.3), but not ovary (OR = 1.2), was significantly more common among women with a personal history of any of these four cancers (all P < 0.05); the pattern of the ORs suggested strongly that the clustering tended to be site-specific. Age-adjusted relative risks (RR) of incident colon cancer over 5 years of follow-up (N = 237) were calculated with regard to family history. Colon cancer incidence was increased among women with a family history of breast (RR = l.3), uterine (RR = 1.4), colon (RR = l.5), and ovarian (RR = 1.3) cancers, although none of the risk estimates achieved statistical significance. RR was, however, significantly related to the number of different cancer sites reported among family members (P_trend = 0.008). These data on a representative sample of postmenopausal women suggest that family histories of colon, breast, uterine, and ovarian cancers are associated with an increased risk of cancer at the same site, but provide little support for the hypothesis that Lynch syndrome II is a non-random occurrence. © 1993 Wiley-Liss, Inc.     

Association between family history of cancer and breast cancer defined by estrogen and progesterone receptor status

There are recent data to suggest that risk factors for breast cancer may differ according to whether the tumor expresses detectable levels of the estrogen receptor (ER) and progesterone receptor (PR). While a family history of breast cancer is one of the most consistent predictors of the disease, we recently reported a modest inverse association with ER+PR− tumors. However, the definition of a family history of cancer did not consider second-degree relatives or cancer sites that may be etiologically related. The current report presents additional data analysis from the Iowa Women's Health Study, a prospective population-based cohort study conducted among 41,837 postmenopausal women. At baseline in 1986, respondents provided information on family history of cancers of the breast, ovaries, or uterus/endometrium in their mothers, sisters, daughters, maternal and paternal grandmothers, and maternal and paternal aunts. Data on family history of prostate cancer in fathers and brothers and age at onset of breast cancer in mothers and sisters were collected in 1992. Cohort members were followed for cancer incidence through the statewide tumor registry. After 7 years and more than 235,000 person-years of follow-up, 939 incident cases of breast cancer were identified. Information was obtained from the tumor registry on ER (+/−) and PR (+/−) status for 610 cases (65.0%). A family history of breast cancer in first-degree relatives was associated with increased risk (relative risk [RR] = 1.4; 95% confidence interval [CI]: 1.1–1.6) for all receptor-defined subtypes of breast cancer except ER+PR− tumors (RR = 0.7; 95% CI: 0.3–1.4). These results were unchanged when data on second-degree relatives were included. When the onset of breast cancer in relatives occurred at or before the age of 45 years, increased risks were evident only for ER−PR+ and ER−PR− tumors (RR = 2.3 and 3.3, respectively). Conversely, when relatives were affected with breast cancer after the age of 45 years, increased risks were most apparent for ER+PR+ and ER−PR+ tumors (RR = 1.3 and 3.2, respectively). A family history of prostate cancer in first-degree relatives was associated with a 1.2-fold increased risk of breast cancer (95% CI: 0.98–1.50), largely a reflection of the association with ER−PR− tumors (RR = 1.5; 95% CI: 0.8–3.0). The small numbers of cases in some categories and the corresponding wide CIs preclude definitive conclusions, but these data are at least suggestive that joint stratification of breast tumors on ER and PR status may be useful in partitioning breast cancer families into more homogeneous subsets. © 1996 Wiley-Liss, Inc.     

Familial aggregation of breast cancer with early onset lung cancer.

Site-specific familial aggregation and evidence supporting Mendelian codominant inheritance have been shown in lung cancer. In characterizing lung cancer families, a number of other cancers have been observed. The current study evaluates whether first-degree relatives of early onset lung cancer cases are at increased risk of breast cancer. Families were identified through population-based lung cancer cases and controls under 40 years of age. Cases were ascertained through the Metropolitan Detroit SEER registry; controls through random-digit dialing. Data were available for 384 female relatives of 118 cases and 465 female relatives of 161 controls. Breast cancer in relatives was evaluated after adjusting for age, race, sex, and smoking status of each family member and the sex and age of the probands. A positive family history of early onset lung cancer increased breast cancer risk among first-degree relatives 5. 1-fold (95% CI, 1.7-15.1). Relatives of cases with adenocarcinoma of the lung were at highest risk (RR = 6.3, 95% CI 2.0-20). Mean age of breast cancer diagnosis among relatives of cases was 52.2 years and not statistically different from relatives of controls. Three case families also reported early ovarian cancers (mean age of diagnosis of 35 years). These findings suggest that shared susceptibility genes may act to increase risk of early onset lung and breast cancer in families.     

Referral of patients with a family history of breast/ovarian cancer--GPs' knowledge and expectations

BACKGROUND: Primary care is expected to play a significant role in the management of patients with genetic problems. Currently, this particularly involves patients with a family history of cancer. If GPs are to exercise their gatekeeper role efficiently in this area, they must be able to evaluate genetic risk and make appropriate referral decisions. OBJECTIVES: The aim of this study was to examine GPs' ability to assess risk and to make appropriate referral decisions for women with a family history of breast/ovarian cancer, and to determine their expectations of a referral to secondary care. METHOD: A questionnaire survey was carried out of the 282 GP principals working within Bedfordshire Health Authority. GPs were asked to make decisions for six simulated cases of women presenting with a family history of breast or ovarian cancer. RESULTS: A total of 164 (58%) GPs returned completed questionnaires. Across the six family histories, the percentage of GPs making an appropriate risk assessment ranged from 21% [95% confidence interval (CI) 14-27%] to 63% (95% CI 56-71%), and an appropriate referral decision ranged from 40% (95% CI 32-48%) to 80% (95% CI 73-86%). Regardless of their accuracy of risk assessment, most GPs were consistent in deciding not to refer low risk women and to refer moderate and high risk women (range 71-85% of GPs for the six family histories). Only 43 (26%, 95% CI 20-33%) of GPs knew the three most important criteria for risk assessment. CONCLUSIONS: GPs require more help and education to enable them to perform their gatekeeper role satisfactorily when assessing patients with a family history of breast/ovarian cancer.     

Hysterectomy, tubal sterilization, and the risk of breast cancer

Studies suggest that hysterectomy and tubal sterilization may alter the function of the remaining ovaries. Conceivably, this effect could alter breast cancer risk. To investigate whether these surgeries affect breast cancer risk, the authors analyzed data collected between December 1, 1980, and April 30, 1983, in a population-based, case-control study of women aged 20-54 years, the Cancer and Steroid Hormone Study. Compared with never-sterilized women, women with hysterectomy and no remaining ovaries had a decreased risk of breast cancer (relative risk (RR) = 0.7, 95% confidence interval (CI) = 0.6-0.8). Risk was lowest in women who had their surgery before age 40 years or 15 or more years in the past; surgery at an early age provided greater protection than surgery in the distant past. Hysterectomy with one or two remaining ovaries was also inversely associated with breast cancer risk (RR = 0.8, 95% CI = 0.7-0.9), but no relation was found with age at surgery or time since surgery. Women with tubal sterilization had a slightly increased risk of breast cancer, which was of borderline statistical significance (RR = 1.2, 95% CI = 1.0-1.3). However, no relation was found with age at surgery or time since surgery. The data suggest that hysterectomy with bilateral oophorectomy decreases the breast cancer risk in women aged less than 55 years, possibly by curtailing ovarian function at a critical period. However, neither hysterectomy without bilateral oophorectomy nor tubal sterilization appears to substantially alter breast cancer risk in women of this age.     

A prospective study of the development of breast cancer in 16,692 women with benign breast disease

The authors studied the relation between benign breast disease and subsequent breast cancer in 16,692 women with biopsy-diagnosed benign breast disease who had participated in the Breast Cancer Detection Demonstration Project throughout the United States. Women were classified into one of five benign breast disease categories: atypical hyperplasia, proliferative disease without atypia, nonproliferative disease, fibroadenoma, and other benign breast disease. A total of 485 incident cases of breast cancer were identified in the women from August 1973 to February 1986 after a median follow-up period of 8.3 years from the diagnosis of benign breast disease. Age-adjusted incidence rates were calculated for benign breast disease types stratified by family history and calcification status. Relative risk (RR) estimates of breast cancer for women in the five benign breast disease categories, compared with the screened women who did not develop recognizable breast disease (normal subjects), were computed using the proportional hazards model. Results indicated that risk was associated with the degree of epithelial atypia. Over all age groups, women with nonproliferative disease, proliferative disease without atypia, and atypical hyperplasia displayed progressively increasing risks of 1.5, 1.9, and 3.0, respectively, compared with normal subjects, with 95% confidence intervals (CI) exceeding unity. Particularly high risk was seen among women under age 46 years with atypical hyperplasia (RR = 5.7, 95% CI 3.0-10.6). Women with fibroadenoma as the only indication of their benign breast disease had a relative risk of 1.7, with a lower 95% confidence limit of 1.0. No increased risk was seen for women with other benign breast disease. Positive family history (RR = 1.8) and calcification (RR = 1.2) significantly increased a woman's risk proportionately over the risk associated with each benign breast disease subtype. The authors conclude that the risk of developing breast cancer varies by category of benign breast disease and is directly related to the degree of epithelial atypia.     

A prospective study of job strain and risk of breast cancer

BACKGROUND: There is conflicting evidence on whether stress is a risk factor for breast cancer. The present study examined prospectively the relationship between stress at work and risk of breast cancer. METHODS: Participants comprised 26 936 postmenopausal women in the Nurses' Health Study ages 46-72 who were in paid employment, and who had no previous history of cancer. Multivariate-adjusted regression analysis was used to examine the relationship between job strain (measured by the Karasek Job Content Questionnaire in 1992) and risk of incident invasive and in situ breast cancer. RESULTS: From 1992 through 1994, 219 women were diagnosed with breast cancer. No evidence was found for a relationship between job stress and risk of breast cancer. Compared with women in low strain jobs, the multivariate-adjusted relative risks of breast cancer were RR = 0.78 (95% CI : 0.52-1.16) for high-strain jobs; RR = 0.76 (95% CI : 0.49-1.17) for active jobs; and RR = 0.94 (95% CI : 0.67-1.34) for passive jobs. Although job strain was related to less breast cancer screening among women in highly demanding jobs, it was not associated with tumour size. CONCLUSIONS: Job stress was not related to an increase in the incidence of breast cancer in the present cohort of nurses.     

A prospective study of fruits, vegetables, and risk of endometrial cancer

Case-control studies support a lower risk of endometrial cancer associated with greater vegetable consumption but not fruit consumption. One prospective study suggested an inverse association with fruits and vegetables combined. The authors examined associations for vegetables and fruits separately among women in the American Cancer Society's Cancer Prevention Study II Nutrition Cohort. After exclusions, 41,400 postmenopausal women completed a questionnaire on diet, lifestyle, and medical history at baseline in 1992-1993. Information on diet was updated in 1999; historical dietary information from 1982 was also available. The authors identified 435 eligible cases of endometrial cancer through 2003. In multivariate models, neither fruit consumption (top quintile vs. bottom: rate ratio (RR) = 1.24, 95% confidence interval (CI): 0.90, 1.70; p-trend = 0.30) nor vegetable consumption (RR = 1.21, 95% CI: 0.89, 1.65; p-trend = 0.24) at baseline was associated with risk. Results were similar when diet was cumulatively updated. Only among women who had never used hormone replacement therapy was the risk of endometrial cancer lower in the highest (vs. lowest) tertile of fruit (RR = 0.75, 95% CI: 0.52, 1.07; p-interaction = 0.03, p-trend = 0.11) or vegetable (RR = 0.80, 95% CI: 0.57, 1.13; p-interaction = 0.01, p-trend = 0.29) consumption. This prospective study does not support an association between vegetable or fruit consumption and endometrial cancer.