Do younger female breast cancer patients have a poorer prognosis? Results from a population‐based survival analysis

Younger women who develop breast cancer are hypothesized to have poorer survival rates than women who develop it at a later stage in life. Several studies have suggested that differences in biologic characteristics of breast cancer in younger (premenopausal) and older (postmenopausal) women may account for the prognostic variation. This population-based cohort study reports on survival rates of breast cancer in Singapore and examines the hypothesis that younger breast cancer patients have a poorer prognosis. A total of 6,397 breast cancer patients diagnosed from 1968 to 1992 were identified from the population-based cancer registry and followed up through 1997. Outcome measures were relative survival rates (RSRs) calculated using Hakulinen's method and excess hazards ratios (HRs) derived from a regression model based on relative survival. The 2-, 5- and 10-year RSRs were worse among those aged > 75 (65%, 48% and 39%, respectively). The best survival rates were seen among those aged 40-44 (84%, 67% and 56%). Patients younger than 35 years faired reasonably well (79%, 60% and 50%). When the data were stratified according to clinical stage and calendar year, the highest risk of excess deaths was found in women > or = 75 years old. In patients with localized cancer and/or regional metastases, those in the 35-39 age group had the lowest excess risk. In patients with distant metastases, those younger than 35 years of age had the lowest excess risk of death. At the population level, younger women (< 45 years) with breast cancer in Singapore have higher relative survival rates.     

Mammographic density and the risk of breast cancer in Japanese women

Using an automated method for detecting mammographic mass, the authors evaluated the relation between quantitatively measured density and the risk of breast cancer in a case-control study among Japanese women. The case subjects were 146 women newly diagnosed and histologically confirmed with breast cancer at a general hospital. A total of 659 control women were selected from those who attended a breast cancer mass screening at this hospital. Significantly increased odds ratios (ORs) of breast cancer were observed for breast densities of 25-49 and 50-74%, but not for densities of 75-100% as compared with 0% in premenopausal women after controlling for covariates (ORs = 4.0, 4.3, and 1.4, respectively). In postmenopausal women, ORs were significantly increased for breast densities of 25-50% (OR = 3.0) and 50-100% (OR = 4.2). Total breast area was significantly associated with the risk of breast cancer independent of density percent or dense area in postmenopausal women. These data suggested that mammographic density was associated with the risk of breast cancer in Japanese women as is the case in Caucasian women. However, the associations of the risk of breast cancer with breast size and a high breast density greater than 75%, needs to be confirmed in future studies.     

Glutathione S-transferase M1 and T1 genetic polymorphisms,alcohol consumption and breast cancer risk

Alcohol consumption has been inconsistently associated with breast cancer risk. Recent studies suggest that genetic polymorphisms of glutathione S-transferases (GSTs) may modify this relation. To determine if breast cancer risk is associated with GSTM1 and GSTT1 genetic polymorphisms, and to evaluate the effect modification between GST genotypes and alcohol consumption in the risk of breast cancer, we conducted a case-control study in the state of Connecticut in the period 1998 and 2001. Cases were histologically confirmed, incident breast cancer patients in New Haven County, CT. Controls were randomly selected from women histologically confirmed to be without breast cancer. The study results show that, while GSTM1 genotypes were not associated with breast cancer risk, GSTT1-null genotype was associated with a significant 90% increased risk for postmenopausal women (OR=1.9, 95% CI 1.2-3.0). Analysis by GST genotypes and alcohol consumption shows that GSTM1A ever-drinking women had a 2.5-fold (OR=2.5, 95% CI 1.1-5.5) increased risk of breast cancer compared to the GSTM1A never-drinkers, and the risk increases with duration and daily amount of alcohol consumption. Postmenopausal women with GSTT1-null genotype, who consumed a lifetime of >250 kg of spirit-equivalents, had an almost seven-fold increased risk (OR=6.8, 95% CI 1.4-33.9), and drinking commencing at younger ages appears to carry a higher risk. An OR of 8.2 (95% CI 1.2-57.4) was observed for those with GSTM1A, and GSTT1-null genotypes who had consumed a lifetime of >250 kg of spirit-equivalents. In conclusion, alcohol consumption may increase breast cancer risk among those who carry susceptible GST genotypes.     

Lactation and breast cancer risk: a case-control study in Connecticut

In this report, we examined the relationship between lactation and breast cancer risk, in a case-control study of breast cancer, conducted in Connecticut between 1994 and 1998. Included were 608 incident breast cancer cases and 609 age frequency matched controls, aged 30-80 years old. Cases and controls were interviewed by trained study interviewers, using a standardized, structured questionnaire, to obtain information on lactation and other major risk factors. Parous women who reported ever lactation had a borderline significantly reduced risk of breast cancer (OR = 0.83, 95% CI, 0.63-1.09). An OR of 0.53 (95% CI, 0.27-1.04) was observed in those having breastfed more than 3 children compared to those who never lactated. Women having breastfed their first child for more than 13 months had an OR of 0.47 (95% CI, 0.23-0.94) compared to those who never breastfed. Lifetime duration of lactation also showed a risk reduction while none of the ORs were statistically significant. Further stratification by menopausal status showed a risk reduction related to lactation for both pre- and postmenopausal women, while the relationship is less consistent for the latter. These results support an inverse association between breastfeeding and breast cancer risk.     

Induced abortions and the risk of all cancers combined and site-specific cancers in Shanghai

Although some previous case–control studies found an increased risk of breast cancer in women who had an induced abortion, the evidence from prospective studies suggests that induced abortions do not cause breast cancer. We have assessed risks of 12 types of cancer in women who have had induced abortions in a prospective study in China. Female textile workers (n = 267,400) completed a baseline questionnaire (1989–1991) that ascertained information on the major risk factors for breast cancer, contraceptive use, and induced abortions and were actively followed until July 2000. Cox Proportional Hazards analysis was used to calculate incidence rate ratios for specific types of cancer in women who ever had an induced abortion and by number of induced abortions. Women who had had an abortion were not at increased risk of cancer. There was a significant reduction in risk of uterine corpus cancer in women who had ever had an induced abortion, and a significant decreasing trend in risk with increasing number of induced abortions. No convincing associations with other cancers were observed. Women who have induced abortions after a live birth are not at increased risk of cancer and induced abortions may reduce risk of cancer of the corpus uteri. Performed in the Department of Kinesiology and Community Health, University of Illinois at Urbana Champaign and Program in Epidemiology, Fred Hutchinson Cancer Research Center     

Radiation dose,chemotherapy, hormonal treatment and risk of second cancer after breast cancer treatment

In total, 281 of the 7711 women who were initially treated for breast cancer between 1954 and 1983 at the Gustave Roussy Institute developed a second malignant neoplasm (SMN) other than second primary breast cancer and nonmelanoma skin cancer at least 1 year after breast cancer treatment. We carried out a nested case-control study to determine the overall relationship between the dose of radiotherapy received at a given anatomical site and the risk of SMN at the same site. In total, 75% of the cases of SMN were previously treated by radiotherapy, as compared to 73% of the controls. In the irradiated patients, the median local dose was higher among cases (3.1 Gy) than among controls (1.3 Gy). More than 40% of the irradiated patients received a local dose of less than 1 Gy. A purely quadratic relationship was observed between the dose of radiation received at an anatomical site and the risk of SMN at this site. According to the quadratic model, the excess risk of SMN was 0.2% (95% CI 0.05-0.5%) when the target organ received 1 Gy. This risk did not differ significantly according to age at the time of radiotherapy (<40 vs >or=40 years). The risk of SMN was 6.7-fold higher for doses of 25 Gy or more than in the absence of radiotherapy. No carcinogenic effect of chemotherapy was observed and a dose-effect relationship between the length of tamoxifen treatment and SMN occurrence was found. This relationship was limited to endometrial cancers and did not modify the relationship with radiation dose. Our results suggest that high radiation doses slightly increase the risk of second malignancies after breast cancer.     

Ovarian cancer risk in premenopausal and perimenopausal women treated with Tamoxifen: a case-control study

As tamoxifen stimulates ovarian steroidogenesis in premenopausal women, induces ovulation and increases the incidence of benign ovarian cysts, there has been concern that it might also increase ovarian cancer risk in women treated premenopausally. In a national case-control study in Britain, treatment histories were collected for 158 cases of ovarian cancer after breast cancer diagnosed at ages under 55 years and 464 controls who had breast cancer at these ages without subsequent ovarian cancer. Risk of ovarian cancer was not raised for women overall who had taken tamoxifen (odds ratio (OR)=0.9, 95% confidence interval (CI) 0.6-1.3) or for those treated when premenopausal (OR=1.0, 95% CI 0.6-1.6) or perimenopausal (OR=0.7, 95% CI 0.2-2.4). There was also no relation of risk to daily dose, duration or cumulative dose of tamoxifen, or time since last use. There was, however, a significantly raised risk in relation to non-hormonal chemotherapy. The results suggest that tamoxifen treatment of premenopausal or perimenopausal women does not materially affect ovarian cancer risk, but that non-hormonal chemotherapy might increase risk.     

The Feasibility of Women at High Risk for Breast Cancer Participating in Chemoprevention Trials

Abstract

There is significant interest in developing chemoprevention trials for women at high risk for breast cancer, yet it is not clear how acceptable these strategies are. Results of clinical trials with tamoxifen have demonstrated a reduction in the incidence of breast cancer in women at increased risk, but rates of participation in such trials have been lower than expected. No previous studies have assessed the attitudes of high-risk women toward participating in chemoprevention trials using drugs causing ovarian suppression. All women who had attended a large familial cancer clinic in Sydney, New South Wales, between 1994 and 2000 who were eligible for the Raloxifene and Zoladex Research study being piloted in the United Kingdom at the time were approached. Telephone interviews were conducted with the 35 high-risk women willing to participate in this study. Almost half the women surveyed expressed willingness to participate in a randomized trial, and slightly fewer women considered participating in a nonrandomized trial. The women who would consider participating were younger than those who would not. The most frequently mentioned reasons for interest in participating in trials were to aid research, help others, and learn more, which indicates that altruism may have played a significant part in the women's willingness to participate. Most women interviewed were participating in risk reduction and early detection strategies and expressed high interest in research screening tests. Given the interest in randomized trials and the fact that women at high risk for breast cancer consider the side effects as mainly acceptable, undertaking such trials may be worthwhile.     

The American Cancer Society guidelines for breast screening with magnetic resonance imaging: an argument for genetic testing

BACKGROUND.

The American Cancer Society (ACS) guidelines for screening with breast magnetic resonance imaging (MRI) recommend MRI for women who have a lifetime risk ≥20% of developing breast cancer. Genetic testing for breast cancer gene (BRCA) mutations is offered to women who have a risk ≥10% of carrying a mutation. The objectives of the current study were 1) to identify the number of women in a breast cancer screening population who had ≥20% lifetime breast cancer risk and, thus, were candidates for screening MRI; and 2) to determine the number of women who had ≥10% risk of BRCA mutation yet had <20% lifetime risk of breast cancer and, thus, may not have been identified as candidates for MRI screening.

METHODS.

From 2003 to 2005, women who underwent screening mammography completed a self‐administered questionnaire regarding breast cancer risk factors. For each patient, the lifetime breast cancer risk and the risk of BRCA mutation was determined by using the computerized BRCAPRO breast cancer risk‐assessment model.

RESULTS.

Of 18,190 women, 78 (0.43%) had ≥20% lifetime risk of breast cancer, all of whom had ≥10% risk of carrying a BRCA mutation. An additional 374 women (2.06%) had <20% lifetime breast cancer risk but ≥10% risk of mutation. Overall, there were 183 (1%) predicted mutation carriers, 27 women (0.15%) who had ≥20% lifetime risk of breast cancer, and 62 women (0.34%) who had ≥10% risk of mutation but <20% lifetime breast cancer risk.

CONCLUSIONS.

The ACS guidelines for breast MRI screening may systematically exclude MRI screening for many women who have a substantial risk for BRCA mutation. The current results demonstrated a need for greater awareness of breast cancer risk factors in the screening mammography population, so that high‐risk women can be identified and given access to genetic testing and counseling regarding all risk‐reducing interventions. Cancer 2008. © 2008 American Cancer Society.     

Risk of endometrial cancer following cessation of menopausal hormone use (Washington, United States)

While there are a number of benefits to the health of postmenopausal women from use of unopposed estrogens, the increased risk of endometrial cancer related to these hormones has led many women to use combined estrogen-progestogen therapy instead, or not to use hormones at all. Most women who take hormones do so only in the early portion of their postmenopausal years, so the risk of endometrial cancer following cessation of use might bear heavily on the overal risk/benefit evaluation. We analyzed data from a case-control study of women in western Washington (United States) to assess the magnitude of excess risk of endometrial cancer following discontinuation of estrogen use. Cases (n=661) consisted of women aged 45 to 74 diagnosed between 1985 and 1991 who resided in one of three counties in Washington State. Controls (n=865) were identified by random-digit dialing. Subjects were interviewed in-person to ascertain current and prior hormone use. The analysis was restricted to women who had not received combined estrogen-progestin therapy. Among women who had used unopposed estrogens at some time, risk of endometrial cancer declined as time since last use increased. Nonetheless, even among women who used these hormones for just a few years, the risk remained elevated by 30 to 70 percent almost a decade after cessation. These results, combined with those of most (but not all) other studies of this issue, suggest that a woman who has discontinued unopposed estrogen therapy may retain a small increased risk of endometrial cancer for a long period of time.Division of Public Health Sciences, Fred Hutchinson Cancer Research Center, the Department of Epidemiology, University of Washington Department of Biostatistics University of Washington, Seattle, WA. Department of Epidemiology, University of Washington, Seattle, WA 98195, USA. This research was supported by US National Cancer Institute contracts R01 CA47749 and R35 CA39779.     

Recency,duration, and progestin content of oral contraceptives in relation to the incidence of endometrial cancer (Washington,USA)

Women who have used combined oral contraceptives (COC) have a reduced risk of endometrial cancer relative to that of women who have never used oral contraceptives, but it is unclear whether the size of the reduction is influenced by the progestin content of the preparation. We analyzed data from two population-based case-control studies of endometrial cancer to investigate this question. Among women aged 40 to 59 years who were residents of King or Pierce Counties, Washington (United States), incident cases who were diagnosed during 1975–77 or 1985–87 were identified. Personal interviews were conducted with 316 such women and their responses compared with those of 501 controls who were selected by household surveys or random-digit dialing. A reduced risk of endometrial cancer associated with COC use was present only among users of five or more years' duration, and even then only in women who were not long-term users of unopposed postmenopausal estrogens. Among these women, the relative risk (RR) of endometrial cancer did not differ according to the progestin potency of the COC used: it was equally low for women who had used a COC with low progestin content (RR=0.2, 95 percent confidence interval [CI]=0.1–0.8) as for women who had used a COC with high progestin content (RR=0.3, CI=0.1–0.9). Our results argue that, if the reduced risk of endometrial cancer in long-term users of COCs is due to the progestins contained in these preparations, that amount of progestin in most COCs exceeds the threshold amount needed to produce this beneficial effect.This project was supported by Grant 5R35CA39779 and Contract NO1-CN-05230 from the US National Cancer Institute.     

Direct-to-patient BRCA1 testing: the Twoj Styl experience

Ideally, a genetic screening program for cancer should offer testing to all women who qualify, and who wish to participate, and who might benefit from the test. As the number of preventive options for women at high risk for hereditary breast cancer expands, the demand for testing increases. However, many women do not have ready access to testing because of cost, and many others have not been recognized by their physicians to be candidates for testing. It is possible to increase women’s awareness about hereditary cancer through the popular press. Genetic testing was offered to 5000 Polish women through an announcement placed in a popular women’s magazine (Twoj Styl) in October 2001. A total of 5024 women who qualified received a free genetic test for three mutations in BRCA1 which are common in Poland. Out of these, 198 women (3.9%) were found to carry a BRCA1 mutation. The overall cost per mutation detected was 630 US dollars—approximately 50–100 times less than the equivalent cost in North America. Genetic counseling was offered to women with a positive test or with a significant family history of breast or ovarian cancer. The great majority of women who took part in the program expressed a high degree of satisfaction and after one year approximately two-thirds of identified mutation carriers had complied with our recommendations for breast cancer screening. We found this model of genetic testing and delivery of genetic information to be very efficient in a population in which founder mutations predominate. There is a need for similar studies in other populations.     

Flavonoid intake and breast cancer risk: a case--control study in Greece

Flavonoids have been investigated for possible inverse associations with various chronic degenerative diseases, but there are no epidemiologic data concerning a possible association between several of the main flavonoid categories and breast cancer risk. We have applied recently published data on the flavonoid content of several foods and beverages on dietary information collected in the context of a large case-control study of 820 women with breast cancer and 1548 control women, conducted in Greece. We found a strong, statistically significant inverse association of flavone intake with breast cancer. The odds ratio for an increment equal to one standard deviation of daily flavone intake (i.e. 0.5 mg day(-1)) was 0.87, with 95% confidence interval 0.77-0.97. The association persisted after controlling for fruit and vegetable consumption, or for other flavonoid intake. This inverse association is compatible with and may explain the reported inverse association of breast cancer with consumption of vegetables, particularly leafy vegetables. After controlling for dietary confounding, there was no association of breast cancer risk with flavanones, flavan-3-ols, flavonols, anthocyanidins or isoflavones.     

Neonatal growth and breast cancer risk in adulthood

Birth size of a woman has been positively associated with her breast cancer risk, particularly before menopause, but no study has investigated neonatal growth in relation to this risk. We conducted a case-control study nested within a population-based cohort of women, born in Sweden between 1901 and 1961, covering all 405 breast cancer patients and 1081 age- and hospital-matched controls, who were born after newborn charts became available. Compared to neonates who lost <200 g after birth and grew at a rate <25 g day(-1) after reaching postnatal weight nadir (ie, the minimum, before starting to regain weight), those who either lost >/=200 g after birth or grew >/=25 g day(-1) after nadir, or both, were at an approximately 50% increased breast cancer risk. The excess risk was striking and statistically significant among women below 50 years of age, but was not evident among older women. Immediate postnatal weight loss (an indicator of water loss, likely to reflect water retention associated with pregnancy hormones) as well as neonatal weight gain rate after the nadir (known to reflect growth hormone levels) was significantly positively associated with premenopausal breast cancer risk.     

Determining the Awareness of and Compliance with Breast Cancer Screening among Turkish Residential Women

Background: Breast cancer is the leading cause of cancer-related deaths in women. Despite being associatedwith high morbidity and mortality, breast cancer is a disease that can be diagnosed and treated early. Materialsand Methods: In this cross-sectional study of 321 women, data were collected by Questionnaire, Breast CancerRisk Assessment Form and Champion’s Health Belief Model Scale. Mann-Whitney U, Kruskal-Wallis, Chisquaredtests and logistic regression were used in the statistical analysis. Results: It was found that only 2.2%of women have high and very high risk levels of breast cancer risk. There is a positive correlation between earlydiagnosis techniques and Health Belief Model Sub-Dimension scores which are sensibility, health motivation,BSE (Breast self-examination) self-efficient perception and negative correlation between mammography barrierscore and BSE barrier score (p 0.05). When factors for not having BSE were examined, it was determined thatthe women who do not have information about breast cancer and the women who smoke have a higher risk ofnot having BSE. Conclusions: It is important to determine health beliefs and breast cancer risk levels of womento increase the frequency of early diagnosis. Women’s health beliefs are thought to be a good guide for planninghealth education programs for nurses working in this area.     

Consanguinity decreases risk of breast cancer--cervical cancer unaffected.

Marriages between third-degree and more distant relatives are common in many parts of the world. Offspring of consanguineous parents have increased morbidity and mortality related to recessive gene disorders. In a population with a high frequency of consanguinity, we examined the frequency of breast cancer (related in part to tumour genes) and cervical cancers (related to virus infection) among offspring of consanguineous and non-consanguineous parents. Study was done prospectively in the United Arab Emirates. Selected were married female citizens, ages 40-65, who attended 12 primary health care clinics for whatever reason. In a face-to-face interview, subjects were asked: (a) about consanguineous marriages in family; (b) if they have or have had breast or cervical cancer; (c) about family history of cancer, cancer screening and other parameters. Tumour diagnosis was confirmed by review of medical records. Of 1750 women invited into study, 1445 (79%) could be used in analysis. Among 579 (40%) women of consanguineous and 866 (60%) of non-consanguineous parents there were 24 and 54 with breast cancer, respectively (RR = 0.66, CI 0.42 - 1.06). In the 40 to 50 age group, breast cancer reported 13 of 446 women of consanguineous and 37 of 633 of non-consanguineous parents (RR = 0.50, Cl 0.27 - 0.93). Cervical cancer had 15 women in consanguineous and 32 in non-consanguineous group (RR = 0.70, Cl 0.38 - 1.28). Number of families with history of breast cancer in consanguineous and non-consanguineous group was 21 and 23, respectively (P = 0.29). The cancer screening rates and other variable values had fairly balanced distribution between the 2 groups. Having consanguineous parents decreases the risk of breast cancer especially in younger women, risk of cervical cancer being unaffected.     

Impact of Implementing B-RSTTM to Screen for Hereditary Breast and Ovarian Cancer on Risk Perception and Genetic Counseling Uptake Among Women in an Academic Safety Net Hospital

BackgroundLower socioeconomic status is strongly associated with decreased perception of cancer risk. Fewer low socioeconomic status women than expected currently access cancer genetic services from which they may benefit.Patients and MethodsWe screened women presenting for a screening mammogram at a safety net academic hospital using the Breast Cancer Genetics Referral Screening Tool Version 3.0 (B-RST^TM), an online tool designed to identify individuals potentially at risk for hereditary breast and ovarian cancer. Participants screening either positive (high risk) or negative (moderate risk) were offered genetic counseling appointments. We used a brief survey to evaluate change in risk perception before and after using B-RST^TM, and after a genetic counseling appointment, if applicable. Barriers to accepting appointments were assessed when participants declined.ResultsOf the 126 participants, 91 (72.2%) screened negative-average risk, 13 (10.3%) screened negative-moderate risk, and 22 (17.5%) screened positive. Of those who screened positive or negative-moderate, 24 (68.6%) expressed interested in a genetic counseling appointment, of which 19 (79.2%) scheduled. Four of the 19 scheduled (21.1%) completed the appointment. We found a significant difference in the number who rated their breast cancer risk correctly on the post-test between the groups who self-rated as low, moderate, or high risk. Those who perceived themselves as high risk were the most likely to rate their risk correctly on the post-test (P < .001).ConclusionWe showed that using B-RST^TM in a safety net academic hospital was effective at identifying women at increased risk for hereditary breast and ovarian cancer.     

Multiparity and the risk of premenopausal breast cancer: different effects across ethnic groups in Singapore

Background The relationship between multiparity and premenopausal breast cancer risk is different in Caucasian, African-American and Hispanic women. For Asian women, this relationship has never been well studied. Methods Within the Singapore Birth Registry, we selected all women who had a first child between 1986 and 2002 (169,936 Chinese, 40,521 Malay, 17,966 Indian). We linked them to the Singapore Cancer Registry data to identify those who developed breast cancer after childbirth (n = 527). We used multivariate Cox analysis to examine the relationship between parity, ethnicity and premenopausal breast cancer risk. Results Compared to Chinese, Malay women had increased and Indian women had decreased risks of premenopausal breast cancer (adjusted Hazard Ratios [HRadj] 1.25 [1.0–1.6] and 0.48 [0.3–0.8] respectively). Multiparity did not modify the risk of premenopausal breast cancer in Chinese and Indians. In Malays there was a significant risk reduction with increasing parity (P _trend 0.037). Malay women with one, two and ≥3 children had premenopausal breast cancer risks (HR_adj) of 1.86 (1.2–3.0), 1.52 (1.1–2.2) and 0.87 (0.6–1.3) respectively compared to their Chinese counterparts. Conclusions The impact of multiparity on premenopausal breast cancer risk differs across ethnic groups in Singapore. Increasing parity reduces the risk of premenopausal breast cancer in Malay, but not in Chinese and Indian women. Uniparous Malay women have twice the risk of premenopausal breast cancer compared to uniparous Chinese. This excess risk disappears after giving birth to ≥3 children. Indian women have lower premenopausal breast cancer risks than Chinese, regardless of their parity status. Helena M. Verkooijen and Karen P. L. Yap are joint first authors.     

The impact of risk‐reducing hysterectomy and bilateral salpingo‐oophorectomy on survival in patients with a history of breast cancer—A population‐based data linkage study

Prophylactic surgery including hysterectomy and bilateral salpingo‐oophorectomy (BSO) is recommended in breast cancer susceptibility gene (BRCA)‐positive women, whereas in women from the general population, hysterectomy plus BSO may increase the risk of overall mortality. The effect of hysterectomy plus BSO on women previously diagnosed with breast cancer is unknown. We used data from a population‐base data linkage study of all women diagnosed with primary breast cancer in Queensland, Australia between 1997 and 2008 (n = 21,067). We fitted flexible parametric breast cancer‐specific and overall survival models with 95% confidence intervals (also known as Royston–Parmar models) to assess the impact of risk‐reducing surgery (removal of uterus, one or both ovaries). We also stratified analyses by age 20–49 and 50–79 years, respectively. Overall, 1,426 women (7%) underwent risk‐reducing surgery (13% of premenopausal women and 3% of postmenopausal women). No women who had risk‐reducing surgery compared to 171 who did not have risk‐reducing surgery developed a gynaecological cancer. Overall, 3,165 (15%) women died, including 2,195 (10%) from breast cancer. Hysterectomy plus BSO was associated with significantly reduced risk of death overall [adjusted hazard ration (HR), 0.69; 95% confidence interval (CI), 0.53–0.89; p = 0.005]. Risk reduction was greater among premenopausal women, whose risk of death halved (HR, 0.45; 95% CI, 0.25–0.79; p < 0.006). This was largely driven by reduction in breast cancer‐specific mortality (HR, 0.43; 95% CI, 0.24–0.79; p < 0.006). This population‐based study found that risk‐reducing surgery halved the mortality risk for premenopausal breast cancer patients. Replication of our results in independent cohorts and subsequently randomised trials are needed to confirm these findings.     

Body size,adult BMI gain and endometrial cancer risk: the multiethnic cohort

The effect of body size and change in BMI on endometrial cancer risk across different racial/ethnic groups has not been studied. We examined the association between body size and endometrial cancer risk and potential effect modification of other risk factors among 50,376 women in the Multiethnic Cohort Study. During 10.3 years of follow‐up, 463 endometrial cancer cases were identified. Epidemiologic data were collected from the baseline questionnaire. “BMI change” was defined as the percentage of body mass index change from age 21 to the time of recruitment. Women who were heavier at age 21 or at baseline (weight ≥ 53.5 kg or ≥ 63.9 kg, respectively) had an increased endometrial cancer risk compared to the lowest quartile of weight during the respective periods. BMI gain ≥ 35% had a RR of 4.12 (95% CI: 2.69, 6.30) compared to the reference group (−5% ≤ BMI change <+5%). Women who averaged an annual BMI gain ≥ 1% had a >3.21‐fold (95% CI: 2.37, 4.33) increased risk compared to women who maintained a stable adult BMI (−0.25 to <+0.25%). The highest risk associated with BMI gain was observed among nulliparous women and postmenopausal women who never used hormone therapy. Although African Americans and Whites showed an increase in risk after ≥35% BMI gain, Japanese Americans showed an increase in risk with much smaller gain (≥5%). In conclusion, adult obesity and increase in adiposity are risk factors for endometrial cancer; and the risk associated with these factors may vary across racial/ethnic groups.