Cancer pattern and survival in a rural district in South India

Background: Cancer pattern data are rare and survival data are none from rural districts of India. Methods: The Dindigul Ambilikkai Cancer Registry (DACR) covering rural population of 2 millions in Dindigul district, Tamil Nadu state, South India, registered 4516 incident cancers during 2003–2006 by active case finding from 102 data sources for studying incidence pattern, of which, 1045 incident cancers registered in 2003 were followed up for estimating survival. House visits were undertaken annually for each registered case for data completion. Cancer pattern was described using average annual incidence rates and survival experience was expressed by computing observed survival by actuarial method and age-standardized relative survival (ASRS). Results: The average annual age-standardized rate per 100,000 of all cancers together was higher among women (62.6) than men (51.9) in DACR. The most common cancers among men were stomach (5.6), mouth (4.2) and esophagus (3.7). Cervical cancer (22.1) was ranked at the top among women followed by breast (10.9) and ovary (3.3). DACR incidence rates were lesser by at least two folds and 5-year survival were on par or lower than Chennai metropolitan registry for most cancers. Five-year age-standardized relative survival (%) in DACR was as follows: all cancers (29%), larynx (48), mouth (42), breast/tongue (38) and cervix (37). Conclusion: Cancer incidence was significantly lower, cancer patterns were markedly different and population-based cancer survival was lower in rural areas than urban areas thus providing valuable leads in estimating realistic cancer burden and instituting cancer control programs in India.     

Educational inequalities in cancer incidence and mortality in Lithuania: A record linkage study

BackgroundThe aim of this study is to describe associations between incidence and mortality by major cancer sites and education in Lithuania.MethodsThe study is based on the linkage between all records of the 2001 population census and all records from Lithuanian Cancer Registry (cancer incidence) and Statistics Lithuania (deaths) for the period between 1 July 2001 and 31 December 2004. Education-specific incidence and mortality rate ratios were estimated by means of multivariate Poisson regression models.ResultsWe found both the positive and inverse educational gradients in cancer incidence and mortality. The risk of developing cancer (all sites) was lower among men and women with the lowest education, whereas cancer mortality was higher among lower educated men. The higher educational level was also associated with an increased risk of prostate cancer among men and an increased risk of breast cancer among women. However, prostate cancer mortality was the highest in the lowest education group, whereas breast cancer mortality among women did not show any statistically significant differences. Lower educated men had significantly higher incidence and mortality due to lung and stomach cancers. Strikingly high incidence and mortality due to cervix cancer was observed among women with secondary and lower than secondary education.ConclusionThe results point to inequalities in early diagnosis and survival from cancer and failures ensuring equal access to medical care. Further more in-depth studies are needed in order to understand the nature and determinants of these inequalities.     

Increase in breast cancer incidence among older women in Mumbai: 30-year trends and predictions to 2025

Background: Increasing trends in the incidence of breast cancer have been observed in India, including Mumbai. These have likely stemmed from an increasing adoption of lifestyle factors more akin to those commonly observed in westernized countries. Analyses of breast cancer trends and corresponding estimation of the future burden are necessary to better plan rationale cancer control programmes within the country. Methods: We used data from the population-based Mumbai Cancer Registry to study time trends in breast cancer incidence rates 1976–2005 and stratified them according to younger (25–49) and older age group (50–74). Age-period-cohort models were fitted and the net drift used as a measure of the estimated annual percentage change (EAPC). Age-period-cohort models and population projections were used to predict the age-adjusted rates and number of breast cancer cases circa 2025. Results: Breast cancer incidence increased significantly among older women over three decades (EAPC = 1.6%; 95% CI 1.1–2.0), while lesser but significant 1% increase in incidence among younger women was observed (EAPC = 1.0; 95% CI 0.2–1.8). Non-linear period and cohort effects were observed; a trends-based model predicted a close-to-doubling of incident cases by 2025 from 1300 mean cases per annum in 2001–2005 to over 2500 cases in 2021–2025. Conclusions: The incidence of breast cancer has increased in Mumbai during last two to three decades, with increases greater among older women. The number of breast cancer cases is predicted to double to over 2500 cases, the vast majority affecting older women.     

Recent trends in breast cancer incidence rates in the Loire-Atlantique,France: A decline since 2003

Background: A recent decline in breast cancer incidence rates has been reported in the United States and in Europe. This decrease has been partly attributed to the reduced use of hormone replacement therapy (HRT). No study in Europe has detailed recent breast cancer incidence trends both by hormonal receptor status and mode of detection at an individual level. Methods: We examined trends in breast cancer incidence rates in the French administrative area of Loire-Atlantique between 1991 and 2007, by age, mode of detection, histological subtype, estrogen/progesterone receptor (ER/PR) status and grade. Annual age-standardized breast cancer incidence rates were estimated using the Loire-Atlantique and Vendée Cancer Registry data. Annual percentage changes (APCs) were estimated using an age-adjusted Poisson regression model. Results: Incidence rates of breast cancer increased 3.5% per year in 1991–2003, dropped ?4.3% per year in 2003–2006 and increased in 2007 (9.1%). Stratified analyses by age groups showed that the decrease concerned predominantly women aged 50–64 years, whereas an increasing proportion of cancers detected by organized screening was observed in this age group. Among these women, the decline of incidence particularly concerned positive estrogen and progesterone receptor tumors, lobular subtype tumors, and low-grade tumors. Conclusion: The drop in breast cancer incidence rates observed between 2003 and 2006 in women 50–64 years old was greater for ER+PR+ tumors. During the same period, the incidence of breast cancers diagnosed by organized screening increased. These patterns appear consistent with an impact of the reduced use of HRT.     

Women cancers in India: Incidence,trends and their clinical extent from the National Cancer Registry Programme

BackgroundTo provide a comprehensive assessment of women cancer in India utilizing the systematically collected data on all cancers by the National Cancer Registry Programme (NCRP).MethodsThe study examined 10,2287 cancer cases among women cancers providing cancer burden for major anatomical sites. Aggregated data of 28 PBCRs and 58 HBCRs under NCRP for 2012–16 was analysed for incidence rates, trends, cumulative risk of developing cancer, stage at detection and treatments offered.ResultsStudy results have found region –wide variation of women cancers by indicating highest proportions in western followed by southern region of India. North-Eastern region had lowest proportion. It was observed that breast is highest ranking cancer in most registry areas of urban agglomerations of country while cancer cervix was leading site in registries of rural areas like Barshi (15.3) and Osmanabad &Beed (13.1). States of Mizoram (23.2) and Tripura (9.5) along with Pasighat, Cachar and Nagaland. Median age of occurrence for women for these anatomical sites ranged from 45 to 60 years of age. For cancer breast, cervix and ovary –most cases were detected with regional spread. These findings were different for cancer corpus uteri where registries have reported higher proportions (49.3 %) of localized stage at detection. Loco regional cancers had higher proportions of multimodality treatments.ConclusionStudy provides a foundation for assessing the status of women cancers in the country. Variations between geographies would guide appropriate support for action to strengthen efforts to improve cancer prevention and control in underserved areas of the country. This would facilitate advocacy for better investments and research on women cancers.     

Marked increase in breast cancer incidence in young women: A 10-year study from Northern Iran, 2004–2013

IntroductionBreast cancer is the most frequent cancer among women worldwide. Breast cancer incidence in young women is a health issue of concern, especially in middle-income countries such as Iran. The aim of this study is to report the breast cancer incidence variations in Golestan province, Iran, over a 10-year period (2004–2013).MethodsWe analyzed data from the Golestan Population-based Cancer Registry (GPCR), which is a high-quality cancer registry collecting data on primary cancers based on standard protocols throughout the Golestan province. Age-standardized incidence rates (ASRs) and age-specific incidence rates per 100,000 person-years were calculated. Time trends in ASRs and age-specific rates were evaluated using Joinpoint regressions. The average annual percentage change (AAPC) with correspondence 95% confidence intervals (95%CIs) were calculated.ResultsA total of 2106 new breast cancer cases were diagnosed during the study period. Most cases occurred in women living in urban areas: 1449 cases (68%) versus 657 cases (31%) in rural areas. Statistically significant increasing trends were observed over the 10-year study period amongst women of all ages (AAPC = 4.4; 95%CI: 1.2–7.8) as well as amongst women in the age groups 20–29 years (AAPC = 10.0; 95%CI: 1.7–19.0) and 30–39 years (AAPC = 5.1; 95%CI: 1.4–9.0).ConclusionThe incidence of breast cancer increased between 2004 and 2013 in Golestan province amongst all age groups, and in particular amongst women aged 20–39 years. Breast cancer should be considered a high priority for health policy making in our community.     

Trends in breast and cervical cancer in India under National Cancer Registry Programme: An Age-Period-Cohort analysis

BackgroundTrend analysis in cancer quantifies the incidence rate and explains the trend and pattern. Breast and cervical cancers are the two most common cancers among Indian women which contributed 39.4 % to the total cancer in India for the year 2020. This study aimed to report the time trends in cancer incidence of breast and cervical cancer using Age–Period–Cohort (APC) model from five Population Based Cancer Registries (PBCRs) in India for the period of 1985–2014.MethodAge-Period-Cohort model was fitted to five PBCRs of Bangalore, Chennai, Delhi, Bhopal and Barshi rural for breast and cervical cancer for 25−74 age-groups. The Estimated Annual Percent Change (EAPC) was calculated. Rate Ratio (RR) of cohort effects were estimated with a constraint of period slope to be zero (p = 0) since cohort has a stronger association with incidence than period.ResultA significant increase was noted in breast cancer in all PBCRs (EAPC, Range: Delhi, 1.2 % to Bangalore, 2.7 %) while significant decrease in cervical cancer (EAPC, Range: Bangalore -2.5 % to Chennai, -4.6 %) from all the PBCRs including Barshi rural during the period. RR estimates for breast cancer showed increasing trend whereas cervical cancer showed decreasing trend in successive birth cohorts across all five PBCRs.ConclusionIn both breast and cervical cancers, a significant age, cohort and period effect was noted in Bangalore, Chennai and Delhi. Despite period effect, the cohort effect was predominant and it may be attributed to the generational changes in risk factors among cancer breast and cervix.     

Trends in advanced breast cancer incidence rates after implementation of a mammography screening program in a German population

BackgroundMammography screening programs (MSPs) aim to detect early-stage breast cancers in order to decrease the incidence of advanced-stage breast cancers and to reduce breast cancer mortality. We analyzed the time trends of advanced-stage breast cancer incidence rates in the target population before and after implementation of the MSP in a region of northwestern Germany.MethodsThe MSP in the Münster district started in October 2005. A total of 13,874 women with an incident invasive breast cancer (BC) was identified by the population-based epidemiological cancer registry between 2000 and 2013 in the target group 50–69 years. Multiple imputation methods were used to replace missing data on tumor stages (10.4%). The incidence rates for early-stage (UICC I) and advanced-stage (UICC II+) BC were determined, and Poisson regression analyses were performed to assess trends over time.ResultsThe incidence rates for UICC I breast cancers increased during the step-up introduction of the MSP and remained elevated thereafter. By contrast, after increasing from 2006 to 2008, the incidence rates of UICC II+ breast cancers decreased to levels below the pre-screening period. Significantly decreasing UICC II+ incidence rates were limited to the age group 55–69 years and reached levels that were significantly lower than incidence rates in the pre-screening period.DiscussionThe incidence rates of advanced-stage breast cancers decreased in the age groups from 55 years to the upper age limit for screening eligibility, but not in the adjacent age groups. The findings are consistent with MSP lead time effects and seem to indicate that the MSP lowers advanced-stage breast cancer rates in the target population.     

Are prognostic factors more favorable for breast cancer detected by organized screening than by opportunistic screening or clinical diagnosis? A study in Loire-Atlantique (France)

Purpose: Comparisons of breast cancer characteristics between organized and opportunistic screening have been limited. This study was designed to compare characteristics of cancers detected by either organized or opportunistic screening as well as clinically diagnosed cancers in Loire-Atlantique (a French administrative entity), from 2003 to 2007. Methods: This study is based on data from the population-based Loire-Atlantique Cancer Registry. Stage at diagnosis and prognostic characteristics of carcinomas detected by organized screening were compared, by age-adjusted logistic regressions, to those of cancers detected by opportunistic screening and diagnosed clinically. Analyses were restricted to women aged 50–74 years (the age group targeted by the organized screening program) for the 2003–2007 period. Results: Between 2003 and 2007, 2864 invasive and 400 in situ breast cancer cases were diagnosed in women aged 50–74 years in Loire-Atlantique. Compared to cancers diagnosed clinically, cancers detected by organized screening were more likely to be in situ (13.7% vs. 3.8%), diagnosed at an early stage (74.4% vs. 51.3%), have a low SBR grade (grade 1: 35.4% vs. 18.5%), and be positive for estrogen–progesterone receptors (68.3% vs. 59.0%). The distribution of stage at diagnosis and prognostic characteristics between organized and opportunistic screening were similar. Conclusion: These findings are consistent with the hypothesis that breast cancers are detected early by organized screening. Cancer characteristics were similar between the two screening modes. Estimating the impact of mammography screening on mortality in Loire-Atlantique should be the object of further investigations.     

Trends in breast cancer mortality in Trinidad and Tobago—A 35-year study

Background: Breast cancer is the most frequently diagnosed cancer among women worldwide. This study examines the breast cancer mortality patterns and trends in the Caribbean island state, Trinidad and Tobago for the 35-year period, 1970–2004. Methods: A retrospective analysis of the trends in breast cancer mortality from 1970 to 2004 was conducted. Crude mortality per 100,000 women, age-standardized mortality using World Standard population and age-stratified mortality were calculated and comparison was made between age groups above and below 50 years. Results: A general pattern of increase was observed in both crude and age-standardized mortality. The overall average crude mortality was 15.6 per 100,000 women (95% confidence interval (CI) 13.9–17.1) and the average age-standardized mortality was 18.0 per 100,000 women (95% CI 16.7–19.2). There was a pattern of increase in mortality with increasing age. The mortality rate was considerably higher for the age groups above 50 years than those less than 50 years of age both showing an upward trend over the 35-year period. Conclusions: Breast cancer mortality continued to increase over the 35-year period in Trinidad and Tobago. This study did not identify the exact reasons for this increasing trend. However, it is known that Trinidad and Tobago is becoming much more industrialized. It may be speculated that decrease in fertility rates, increase in the incidence of obesity and hormone utilization could have influenced this trend.     

Cohort study of association of risk of breast cancer with cyst type in women with gross cystic disease of the breast.

OBJECTIVE: To assess correlation between type of breast cyst and risk of breast cancer in women with gross cystic disease of the breast. DESIGN: Cohort study of women with breast cysts aspirated between 1983 and 1993 who were followed up until December 1994 for occurrence of breast cancer. SETTING: Major cancer prevention centre. SUBJECTS: 802 women with aspirated breast cysts. MAIN OUTCOME MEASURES: Type of breast cyst based on cationic content of cyst fluid: type I (potassium:sodium ratio > 1.5), type II (potassium:sodium ratio < 1.5), or mixed (both types). Subsequent occurrence and type of breast cancer. RESULTS: After median follow up of six years (range 2-12 years) 15 cases of invasive breast cancer and two ductal carcinomas in situ were diagnosed in the cohort: 12 invasive cancers (and two carcinomas in situ) among the 417 women with type I cysts, two cancers among the 325 women with type II cysts, and one among the 60 women with mixed cysts. The incidence of breast cancer in women with type I cysts was significantly higher than that in women with type II cysts (relative risk 4.62 (95% confidence interval 1.26 to 29.7)). These results were confirmed after adjustment for several risk factors for breast cancer (relative risk 4.24 (1.12 to 27.5)). CONCLUSIONS: The increased risk of breast cancer of women with breast cysts seems to be concentrated among women with type I breast cysts.     

Distribution of multiple myeloma in India: Heterogeneity in incidence across age,sex and geography

BackgroundThis study aimed to investigate the distribution of multiple myeloma (MM) in India and provide a comprehensive narrative about its incidence, including differential patterns across age, sex and geography.MethodsMM cases diagnosed during 2012-14 were obtained from 27 populations based cancer registries in India by consulting the latest National Cancer Registry Programme reports. Crude (CR) and age-specific (ASR) rates of MM incidence were determined. Age-adjusted rates (AARs) were estimated by standardizing the CR values using age-specific weights recommended for LMIC countries (including India) for men and women separately, along with the corresponding 95% confidence interval (95% CI) measures.ResultsAltogether, 1916 MM cases (male/female: 1123/793) were documented (i.e. 1.19% of all cancers, 95% CI: 1.14–1.24%). Overall CR of MM in India was 1.27 (95% CI: 1.20–1.35)/ 100,000 in men and 0.95 (95% CI: 0.89–1.02)/ 100,000 in women, while the corresponding AARs were 1.13 (95% CI: 1.07–1.20) and 0.81 (95% CI: 0.75 – 0.88) per 100,000 respectively. The ASR values increased steadily with age. Most cases belonged to the 60–69 yrs bracket. However, regional and sex-specific differences in MM profile were observed. MM incidence was highest in the Southern and Northern zones, and least in the Northeast. The Northern and Central zones had higher proportion of MM in the 50–59 yrs age group, whereas Eastern zone had higher proportion of cases aged 70 yrs and above.ConclusionIncidence of MM in India is presented. Marked variations in MM incidence were noted with respect to age, sex and geography.     

Incidence,mortality and receptor status of breast cancer in African Caribbean women: Data from the cancer registry of Guadeloupe

BackgroundGeographical disparities in breast cancer incidence and outcomes are reported worldwide. Women of African descent show lower incidence, higher mortality rates and earlier age of onset. We analyzed data from the cancer registry of Guadeloupe for the period 2008–2013.MethodsWe describe breast cancer characteristics by molecular subtype, as well as estimated observed and net survival. We used Cox proportional hazard models to determine associations between cancer subtypes and death rate, adjusted for variables of interest.ResultsOverall, 1275 cases were recorded with a mean age at diagnosis of 57(±14) years. World standardized incidence and mortality were respectively 71.9/100,000 and 14.1/100,000 person-years. Age-specific incidence rates were comparable to European and US populations below the age of 45, and higher in Guadeloupean women aged between 45 and 55 years. Overall, 65.1% of patients were hormone receptor (HR)+ and 20.1% were HR-. Triple negative breast cancers (TNBC) accounted for 14% of all cases, and were more frequent in patients under 40 (21.6% vs. 13.4%, p = 0.02). Five-year net survival was 84.9% [81.4-88.6]. It was higher for HR+/Her2+ and HR+/Her2- subtypes, and lower for HR-/Her2+ and TNBC patients.ConclusionWe found high age-specific incidence rates of breast cancer in women aged 45 to 55 years, which warrants further investigation in our population. However, this population of mainly African descent had good overall survival rates, and data according to subtypes are consistent with those reported internationally. These results may suggest that poorer survival in other African descent populations may not be an inherent feature of the disease but may be amenable to improvement.     

Duration of ovarian hormone exposure and gynecological cancer risk in Korean women: the Korean Heart Study

BackgroundAlthough reproductive and hormonal factors – such as early menarche and late menopause – have been reported as independent risk factors for cancer, few studies have examined these factors in East Asian populations.MethodsWe performed a large prospective cohort study of 66,466 women. Ovarian hormone exposure was defined as length of time between menarche and menopause. Incidence rates for breast, ovarian, endometrial and cervical cancers were examined separately in relation to reproductive lifespan defined as age at menopause minus age at menarche. Multivariable adjusted hazard ratios (HRs) with 95% confidence intervals (95% CIs) were calculated using the Cox proportional hazards model.ResultsWomen with early menarche were at increased risk for developing breast cancer (HR, 1.57, 95% CI, 1.17–2.10) for age at menarche ≤12 years compared to women with age at menarche ≥17 years. Women with late age at menopause (≥52 years) had increased risks for cancers of the breast (HR, 1.59, 95%CI, 1.11–2.28) and ovary (HR, 3.22, 95% CI, 1.09–9.55) compared to women with early menopause (≤45 years of age). Women with longer duration of ovarian hormone exposure (≥40 years) were at increased risk for developing breast cancer (HR, 2.23, 95% CI, 1.35–3.68) as well as endometrial cancer (p for trend, 0.0209).ConclusionsWe showed that longer reproductive spans are associated with an increased risk of breast and endometrial cancer in Korean women.     

Education and risk of cancer in a large cohort of men and women in the United States

Background

Education inequalities in cancer incidence have long been noted. It is not clear, however, whether such inequalities persist in the United States, especially for less common malignancies and after adjustment for individual risk factors.

Methodology/Principal Findings

Within the NIH–AARP Diet and Health Study, we examined the association between education and the risk of developing cancers in a prospective cohort of 498 455 participants who were 50–71 year old and without cancer at enrollment in 1995/96. During a maximum 8.2 years of follow–up we identified 40 443 cancers in men and 18 367 in women. In age-adjusted models, the least educated men (Conclusions/SignificanceWe found a higher risk of malignant disease, particularly smoking– related cancers, among those in the lowest educational attainment category. Only some of the educational gradient is attributable to smoking. The persistence of substantial education inequalities in cancer incidence poses a challenge for etiologic research and public health policy.     

Metabolic syndrome and incidence of liver and breast cancers in Japan

Aim of the study To clarify the relationship between the presence of metabolic syndrome and the incidence of cancer in a general Japanese population. Methods A retrospective cohort study was conducted among 8329 male and 15,386 female subjects between 1992 and 2000. The analysis used five definitions of metabolic syndrome. The information on the site-specific cancer was obtained from the population-based cancer registry. A Cox proportional hazard model was adapted for the statistical analyses. The average follow-up period was 9.1 years. Results The National Cholesterol Education Program Adult Treatment Panel III 2001 criteria of metabolic syndrome revealed that the hazard ratio of metabolic syndrome for liver cancer was 1.89 (95% confidence interval (CI) 1.11–3.22) for males, and 3.67 (CI 1.78–7.57) for females. The hazard ratio for female breast cancer was 2.87 (CI 1.67–4.94). When the analysis was limited to postmenopausal women (55 years of age or older), the ratio increased to 6.73 (CI 2.93–15.43). The NCEP-ATPIII 2001 criteria were superior to the other four proposed criteria for predicting the incidence of cancer. In the statistical model, which included all components of the metabolic syndrome and the metabolic syndrome (present or absent), high blood glucose was a significant associated factor for all sites and liver cancers, whereas the metabolic syndrome was found to be a significant associated factor for breast cancer. Conclusion Metabolic syndrome may play an important role in the incidence of breast cancer. High fasting plasma glucose level is considered to be useful as an associated factor for the incidence of all-sites and liver cancer.     

Educational status,coronary heart disease,and coronary risk factor prevalence in a rural population of India.

OBJECTIVE--To define the association between educational level and prevalence of coronary heart disease and coronary risk factors in India. DESIGN--Total community cross sectional survey with a doctor administered questionnaire, physical examination, and electrocardiography. SETTING--A cluster of three villages in rural Rajasthan, western India. SUBJECTS--3148 residents aged over 20 (1982 men, 1166 women) divided into various groups according to years of formal schooling. RESULTS--Illiteracy and low educational levels were associated with less prestigious occupations (agricultural and farm labouring) and inferior housing. There was an inverse correlation of educational level with age (rank correlation: mean -0.45, women -0.49). The prevalence of coronary heart disease (diagnosed by electrocardiography) was significantly higher among uneducated and less educated people and showed an inverse relation with education in both sexes. Among uneducated and less educated people there was a higher prevalence of the coronary risk factors smoking and hypertension. Educational level showed a significant inverse correlation with systolic and diastolic blood pressure. Logistic regression analysis with adjustment for age showed that educational level had an inverse relation with prevalence of electrocardiographically diagnosed coronary heart disease (odds ratio: men 0.82, women 0.53), hypertension (men 0.88, women 0.56), and smoking (men 0.73, women 0.65) but not with hypercholesterolaemia and obesity. The inverse relation of coronary heart disease with educational level abated after adjustment for smoking, physical activity, body mass index, and blood pressure (odds ratio: men 0.98, women 0.78). CONCLUSION--Uneducated and less educated people in rural India have a higher prevalence of coronary heart disease and of the coronary risk factors smoking and hypertension.     

Risk factors for breast cancer in women biopsied for benign breast disease: A nested case-control study

Aim: Women with a history of benign breast disease are at increased risk of subsequent breast cancer. However, few studies have examined whether established breast cancer risk factors other than histology are associated with an altered risk of breast cancer in women with benign breast disease. We used a nested case-control design within a large, multi-center cohort of women biopsied for benign breast disease (BBD) to estimate odds ratios for breast cancer in association with exposure to a range of personal and lifestyle factors. Methods: Cases were women biopsied for BBD who subsequently developed breast cancer; controls were individually matched to cases on center and age at diagnosis and were women biopsied for BBD who did not develop breast cancer in the same follow-up interval as that for the cases. After excluding women with prevalent breast cancer, 1357 records (661 case records and 696 records) were available for analysis. We used conditional logistic regression to obtain crude and multivariable-adjusted estimates of the association between specific factors and risk of breast cancer. Results: In multivariable analyses age at first live birth, number of pregnancies, and postmenopausal status were inversely associated with risk of breast cancer. The odds ratio for women with age at first birth <25 years and ≥3 pregnancies, relative to nulliparous women, was 0.49, 95% confidence interval 0.13–0.79, and that for postmenopausal women relative to premenopausal women was 0.60, 95% CI 0.37–0.99. Conclusions: Further study of personal factors influencing the risk of breast cancer in women with BBD may help to identify subgroups of the population at increased risk of invasive disease.