Age-specific Breast Cancer Incidence Research Articles

No evidence that breast cancer occurs at higher rates among young Arab women

Background: Breast cancer is often thought to occur at a younger age among Arab women based on the mean or median age at diagnosis, or the proportion of women diagnosed with breast cancer at a young age. Objective: To compare age-specific breast cancer incidence rates among women from selected Arab countries with selected high- and middle-income countries. Methods: We examined population-based, age-specific, national or regional breast cancer incidence data for 2008–2012 and 2013–2017 from Australia, Brazil, Canada, Germany, Japan, United Kingdom, and United States of America, and compared them with data from Algeria, Bahrain, Jordan, Kuwait, Morocco, Qatar, and Saudi Arabia. Results: Breast cancer incidence among young women in the selected Arab countries was comparable to, or even lower than, the selected high- and middle-income countries. In contrast to the continued increase in rates observed in the high- and middle-income countries, the rates tended to plateau or decrease among older Arab women. Age-standardized incidence rates were lower than crude rates in the Arab countries. Conclusion: We found no evidence that Arab women are at higher risk of developing breast cancer at a younger age. The high number of cases among them was probably due to the younger population structure. These findings are important for refining breast cancer screening policies in the region.

Trends in age-specific incidence, mortality, and DALYs of female breast cancer from 1990 to 2021.

Breast cancer is a leading cause of morbidity and mortality among women worldwide. This study aims to analyze the trends in breast cancer incidence, mortality, and disability-adjusted life years (DALYs) across different age groups from 1990 to 2021, and to project the mortality rate for the next decade. Global breast cancer data were analyzed, focusing on three distinct age groups: 15-49 years, 50-69 years, and 70+ years. Joinpoint regression analysis was used to identify periods of significant changes in cancer rate trends (joinpoints). Age-specific annual percent changes (APC) and average annual percent changes (AAPC) were calculated to identify trends over time. Additionally, an autoregressive integrated moving average (ARIMA) model was employed to forecast future mortality rates. The overall incidence of breast cancer increased significantly with an AAPC of 1.6% from 1990 to 2021. The highest increase was observed in the 15-49 years age group (AAPC: 1.3%), while the 70+ years age group showed the lowest increase (AAPC: 0.2%). Mortality rates exhibited a complex pattern, with a modest overall increase (AAPC: 0.8%), a slight increase in the 15-49 years age group (AAPC: 0.4%), and decreases in both 50 and 69 years (AAPC: -0.4%) and 70+ years age groups (AAPC: -0.3%). DALY rates increased slightly overall (AAPC: 0.7%), primarily driven by the 15-49 years age group (AAPC: 0.4%), while the older age groups showed a declining trend (AAPC: -0.4%). Incidence rates are rising across all age groups, with the highest increase observed among younger women (15-49 years). In contrast, older age groups (50 + years) are experiencing improvements in mortality and DALYs. These findings underscore the need for targeted public health interventions, enhanced screening practices, and ongoing advancements in breast cancer treatment to address the evolving burden of this disease across different age groups.

Abstract C072: Geographic disparities in age-specific breast cancer incidence trends in the United States, 2001-2018

Abstract Background: Temporal trends in breast cancer (BC) incidence rates are shown to vary by age and race/ethnicity in the United States (U.S.), but less is known about whether these trends also vary by geography. Methods: We used data from the U.S. Cancer Statistics (USCS) database, a population-based surveillance system of cancer registries covering 99% of the U.S. population, to evaluate trends in age-specific BC incidence rates from 2001-2018 by geography. Incidence rates were calculated for 15-year age groups, including 25-39, 40-54, 55-69, and 70-84 years. We calculated age-specific BC incidence rates stratified by state, region (Midwest, Northwest, South, West), and metropolitan or non-metropolitan designation based on Rural-Urban Continuum Codes. We also calculated rates further stratified by race/ethnicity. For each geographic subgroup, we calculated the average annual percent change (AAPC) in BC incidence using Joinpoint software; multiple permutation testing was used to identify inflection points in trends. Results: We found that BC incidence significantly increased from 2001-2018 in 18, 16, 3, and 15 states, respectively, for the age groups of 25-39, 40-54, 55-69, and 70-84 years. BC incidence significantly decreased in 3, 2, 15, and 1 state(s), respectively, for the age groups of 25-39, 40-54, 55-69, and 70-84 years. We identified regional differences in age-specific BC incidence trends from 2001-2018. In the 25-39 years age group, a significant increase in BC incidence was observed in the Northeast (AAPC=0.56), Midwest (AAPC=0.48), and West (AAPC=0.67), but not in the South. The Northeast and Midwest also experienced a significant increase in BC incidence in the 40-54 years age groups (AAPCs=0.52 and 0.38, respectively). The Midwest and West experienced a significant decrease in BC incidence in the 55-69 years age group (AAPCs = -0.35 and -0.89, respectively). The South was the only region to experience a significant increase in BC incidence in the 70-84 years age group (AAPC=0.28). Trends were mostly consistent between metropolitan and non-metropolitan areas within regions, except that BC incidence in the 55-69 years age group significantly increased in non-metropolitan areas of the South (AAPC = 0.27), but not metropolitan areas of the South. Regional differences were also observed when we further stratified BC incidence rates by race/ethnicity. Conclusions: These findings suggest that geography should be considered when measuring and addressing disparities in BC incidence rates. Additional studies are needed to identify the geographically patterned risk factors, such as certain environmental exposures, that may be contributing to these trends in BC incidence rates. Regional differences in screening practices may also be contributing to trends in older age groups. Citation Format: Rebecca D. Kehm, Josephine M. Daaboul, Mary Beth Terry. Geographic disparities in age-specific breast cancer incidence trends in the United States, 2001-2018 [abstract]. In: Proceedings of the 16th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2023 Sep 29-Oct 2;Orlando, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2023;32(12 Suppl):Abstract nr C072.

Basic Findings of Incidence of Breast Cancer in Allied Hospital Faisalabad, Pakistan: A Retrospective Study.

Breast cancer is the most common malignancy among women worldwide. We aimed to know the past trends of age-specific breast cancer incidence rates in Faisalabad city. A retrospective study was designed at Allied Hospital Faisalabad (AHF), Pakistan from 2014-2018. Overall, 12742 cancer patients presented throughout these years, out of which 3390 were breast cancer cases. Descriptive statistics were computed and the results were presented as counts and percentage for categorical variables. Means and standard errors were computed for the continuous variables. For testing the association among categorical variables, a chi-square test of independence was used and the p-values less than 0.05 are reported as significant. 84.70% patients were diagnosed with invasive breast carcinoma and 15.30% were all other types reported in the Allied Hospital Faisalabad. The incidence of breast cancer was outrageous in the 40-49 year-old age group (1021 patients, 30.12%) and the mean age is 45 in all years. An increase of 34.86% was observed from 2014 to 2018. The comprehensive four-year data (2015 to 2018) were further analyzed for histology, surgery, staging and grading pattern as 2014 files data was insufficient to discuss. The stage III and grade III were most common throughout the years from 2015 to 2018 with 33.9% and 55.71% respectively. Breast cancer is diagnosed more commonly in women than in any other type of cancers in Faisalabad city. There is a need to upgrade the existing hospital facilities to make the women diagnose the cancer at an earlier stage.

Associations of increasing breast cancer incidence with the current drinking habits and the past smoking habits among Japanese women

Background We have reported that age-specific incidence rates of breast cancer among Japanese women increased from 2005 to 2015 in a bimodal distribution pattern, with two peaks in the pre- and postmenopausal age groups. Objectives The present study aimed to assess the associations of the increasing age-specific breast cancer incidence or mortality with the prevalence of obesity and drinking and smoking habits, compared with those in uterine body, female and male colon and lung cancers. Methods Linear correlations of annual rates from 2005 to 2015 of the 10-year age-specific cancer incidence and mortality with the prevalence of obesity (body mass index, 25 and over) and drinking (alcohol, 20 g and over 3 times or more a week) and smoking habits were assessed by Pearson’s correlation coefficients during the same 10-year period (from 2005 to 2015) or the 10-year period 10 years before the cancer incidence and mortality were noted (from 1995 to 2005). Results Positive correlations (r>0.640) were found between the increasing breast cancer incidence and the drinking habit during the same period or the smoking habit during the period 10 years before. Similar but weaker correlations were found for the breast cancer mortality rate increasing with age. Positive correlations were found between the decreasing male lung cancer mortality rate and the smoking habit rate during the period 10 years before. Conclusions The present ecological study indicated that the breast cancer incidence was associated with the current drinking habits and the past smoking habits among Japanese women.

Recent Increase in the Breast Cancer Incidence Among Japanese Women Seems to Correlate With the Prevalence of Drinking and Smoking Habits, but Not Obesity, as a Modern Lifestyle

ObjectivesWe have recently reported that age-specific incidence rates of breast cancer among Japanese women clearly increased from 2000 to 2015 in a bimodal distribution pattern with two peaks at the age groups of 45 to 49 and 60 to 64 years. The present study aimed to assess the association of age-specific breast cancer incidence rates with the prevalence of obesity and drinking and smoking habits among Japanese women, compared with those of uterine body, colon and lung cancers. MethodsAge-specific cancer incidence and mortality rates and the prevalence of obesity and drinking and smoking habits were obtained from national data published by Cancer Information Services or National Institute of Health and Nutrition of Japan. Linear correlations of annual rates from 2005 to 2015 of the 10-year age-specific cancer incidence and mortality with the prevalence of obesity (body mass index, 25 and over) and drinking (alcohol, 20g and over 3 times or more a week) and smoking habits during the same 10-year period or the 10-year period 10 years before the cancer incidence and mortality were assessed by Pearson’s correlation coefficients. ResultsSignificant (p < 0.05) and positive correlations were found between breast cancer incidence and drinking habits during the same period at the age of 50–59 (r = 0.901), 60–69 (r = 0.808) and 70–79 years (r = 0.643) and during the 10-year-before period at 50–59 (r = 0.676); between the incidence and smoking habits during the 10-year-before period at 40–49 (r = 0.897), 50–59 (r = 0.731) and 60–69 (r = 0.696); between the mortality and drinking habits during the same period at 30–39 (r = 0.739), 60–69 (r = 0.817) and 70–79 (r = 712); and between the mortality and smoking habits during the same period at 30–39 (r = 0.733) and during the 10-year-before period at 60–69 (r = 0.663). Similar but less positive correlations for uterine body cancer or more positive correlations for male lung cancer were found. The prevalence of male drinking and smoking habits was decreasing during the 20 years. No positive correlations were found between the breast cancer incidence or mortality and the prevalence of obesity. ConclusionsThe present ecological study demonstrated that the prevalence of drinking and smoking habits, but not obesity, as a modern lifestyle correlated with the recent increase in the age-specific breast cancer incidence among Japanese women. Funding SourcesNone.

Correlation between cumulative mammographic density and age-specific incidence of breast cancer: A biethnic study in Israel.

Women with the most extensive breast density, have a 4- to 6-fold higher cancer risk than women with the lowest density. This cross-sectional study evaluated associations of cumulative mammographic density in two distinct ethnic groups with the respective age-specific breast cancer incidences in the population. The study compared four cohorts of 200 women each aged 35 to 49 and 50 to 74, representing Jewish and Arab ethnicity. Breast density measures were calculated from screening mammograms, using a thresholding software (Cumulus). Breast cancer specific incidence values were obtained from the National Cancer Registry. The percent mammographic density was lower for women aged 50 to 74 than 35 to 49 years, both for Jews: 11.7 vs 23.1 and for Arabs: 11.6 vs 18.3. In contrast, the cumulative density increased with age, from 37.30 to 181.24 in Jews, compared to 21.26 to 108.03 in Arabs. Similar trends in breast cancer incidence rates per 100 000 in the Israeli population were apparent, with an increase from 92.95 to 381.91 in Jews, compared to 48.6 to 244.44 in Arabs. Comparing cumulative density of the cohort with respective age-specific breast cancer incidence in the population yielded a highly significant correlation: Jews; r=.97, P < .0001 and Arabs: r=.86, P=.007. A strong association was found between the log of cumulative density and the log of cancer incidence, as well. Our study identified correlations between cumulative mammographic density and breast cancer incidence in two distinct populations. The findings should prompt research to enhance our understanding of the pathogenesis of breast cancer, and lead to novel insights into measures of prevention.

Epidemiological characteristics and forecasting incidence for patients with breast cancer in Shantou, Southern China: 2006-2017.

This study aimed to explore the epidemiological characteristics of breast cancer and establish an Exponential Smoothing (ETS) and Autoregressive Integrated Moving Average (ARIMA) models to predict the development of incidence in Shantou. This study has a large sample size, strong representativeness, and wide‐ranging and comprehensive medical insurance information, which can fill the gaps in basic epidemiological research on breast cancer in Shantou. Successful completion of this study is a helpful tool to understand the epidemiology of Guangdong Province and Southern China. This study also provides data and scientific references for the government and future research on breast cancer prevention and control. This retrospective study was conducted to describe the epidemic intensity, epidemic distribution, and epidemic trend of breast cancer in Shantou, Guangdong Province, from 2006 to 2017, gathered from the Shantou's Medical Security Bureau covers the whole districts of Shantou. ETS and ARIMA models were used to describe the regional distribution, time distribution, and population distribution of breast cancer in Shantou. Moreover, based on the ARIMA model and ETS model, the incidence trend of breast cancer was predicted during 2018–2022. This study included 5,681 breast cancer patients, majority of whom were aged 50–59 years. The male‐to‐female ratio of the breast cancer patients was about 1:107 (the same ratio of the insured population was 1:1). Female patients accounted for 98.61% of the total insured population. The incidence and mortality rates of female breast cancer were 16.42/100,000 and 0.66/100,000, respectively. Based on the ARIMA model or ARIMA and ETS model, a gradually decreasing trend in the incidence of breast cancer is expected in the future. Comparing the performances of the ARIMA model and ETS model, ARIMA (4, 0, 1) (0, 1, 0) model had a lower the root mean squared error and the mean absolute percentage error than ETS (M, N) model. This population‐based retrospective study showed that the high‐risk age for the age‐specific incidence of female breast cancer was 50–55 years. It is recommended that healthcare administration should strengthen program awareness and education regarding breast cancer prevention and control. It is also possible that feasibility of extrapolating the current methodology to other future studies or broader populations in which the cancer registry data are not available.

Age-specific breast cancer incidence rate in the world.

Age-specific breast cancer incidence rate in the world.

Association of Increasing Age-Specific Breast Cancer Incidence Rates with Drinking Habits but Not Obesity Prevalence, Based on National Data in Japan

Association of Increasing Age-Specific Breast Cancer Incidence Rates with Drinking Habits but Not Obesity Prevalence, Based on National Data in Japan

Abstract 4636: Breast cancer age-specific incidence rates among Ghanaian women by breast cancer risk factors: A study using census and population-based case-control study data

Abstract Introduction: Although breast cancer incidence in sub-Saharan African countries, including Ghana, has been historically low, incidence is rising. Evaluating age-specific incidence rates by breast cancer risk factors may provide etiologic insights. Here we present age-specific incidence rates for breast cancer estimated from the Ghana Breast Health Study (GBHS) for key breast cancer risk factors. Methods: GBHS is a population-based case-control study with 1,071 pathologically confirmed incident invasive breast cancer cases (18-74 years old) diagnosed between 2013-2015 in three hospitals in Accra and Kumasi. A total of 2,094 controls were sampled from the population, and frequency matched by site and age to the cases. Sample weights for controls were calculated using data from the 2010 Ghana Census, adjusted for non-response. Data on incident breast cancer cases in Accra (2012-2014) and Kumasi (2013-2015) were obtained from their respective cancer registries and compared to the incidence rates observed in the GBHS. Using data from GBHS adjusted by sampling weights, we estimated 5-year age-specific breast cancer incidence rates and 95% confidence intervals overall and according to breast cancer risk factors. Results: Age-specific breast cancer incidence rates estimated from the GBHS rose quickly until approximately age 50 when the rate plateaued but still rose (Clemmeson's hook), which was consistent with cancer registry data from Kumasi and Accra. The rates from the GBHS are not significantly different from the cancer registry rates under age 50 but are significantly higher after age 50. While the rates from the GBHS and Accra and Kumasi cancer registries were much lower than rates observed in the SEER registries for African American women, the trends were consistent. Analyses of overall rates by breast cancer risk factors showed that age-specific breast cancer risk was elevated among women with a family history of breast cancer across all ages. Data suggested cross-over interactions for other factors, particularly parity, and breastfeeding among parous women. Specifically, incidence rates were higher for parous than nulliparous women aged 20-35 years, while incidence rates were lower for parous and breastfeeding (among parous) women older than 35 years. Conclusions: Age-specific incidence rates of breast cancer that demonstrate cross-over interactions by risk factors may be important in understanding racial disparities in breast cancer incidence, overall as well as for specific breast cancer subtypes. Elevated risk among young parous women may be indicative of the higher risk associated with early-onset (triple-negative) breast cancer. Citation Format: Brittny Davis Lynn, Jonine Figueroa, Richard Biritwum, Beatrice Wiafe Addai, Baffour Awuah, Joe Net Clegg-Lamptey, Robertson Adjei, Lucy Afriyie, Joel Yarney, Naomi Oyoe Ohene Oti, Daniel Ansong, Seth Wiafe, Louise Brinton, Montserrat Garcia-Closas, Barry Graubard. Breast cancer age-specific incidence rates among Ghanaian women by breast cancer risk factors: A study using census and population-based case-control study data [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 4636.

Breast cancer risk after hysterectomy with and without salpingo-oophorectomy for benign indications

Breast cancer risk has been extensively studied in women with genetic predisposition, that is, mutations in breast cancer genes 1 and 2. Although there are guidelines for performing bilateral salpingo-oophorectomies in individuals with specific genetic risks, oophorectomies are also performed in many women considered to be at average risk of developing breast cancer. The risk of breast cancer in women with average risk who undergo hysterectomy with bilateral salpingo-oophorectomy for benign indications is less clear. This study aimed to estimate breast cancer risk after hysterectomy with and without concomitant bilateral salpingo-oophorectomy for benign indications. From 2001 to 2015, women aged 18 years and older from Kaiser Permanente Northern California who underwent hysterectomy alone and hysterectomy with bilateral salpingo-oophorectomy were identified using the International Classification of Diseases, Ninth Revision, procedure and Current Procedural Terminology codes. Women with a breast cancer gene mutation and previous history of breast cancer or gynecologic cancer were excluded. Descriptive and bivariate analyses were used to describe and compare demographic and clinical characteristics. Breast cancer incidence rates were calculated per 100,000 person-years. Survival analysis and Cox proportional hazard models were conducted to compare the risk of developing breast cancer. Of 49,215 women who underwent hysterectomy, 19,826 had hysterectomy with bilateral salpingo-oophorectomy. Whites, Hispanics, blacks, Asians, and other or unknown comprised 51.2%, 20.3%, 12.7%, 10.4%, and 5.3% of the study population, respectively. The average age of women with hysterectomy alone was 45.5 years compared with 50.8 years for those who had hysterectomy with bilateral salpingo-oophorectomy. During the study period, 915 women received a diagnosis of breast cancer. Age-specific breast cancer incidence rates were higher in women older than 60 years with oophorectomy than hysterectomy alone (471.2 [95% confidence interval, 386.2-556.2] vs 463.0 [95% confidence interval, 349.6-576.5], respectively). After controlling for age, race, income, and Charlson Comorbidity Index, women with bilateral salpingo-oophorectomy had a 14% lower risk of breast cancer than women with hysterectomy alone (hazard ratio, 0.86; 95% confidence interval, 0.75-0.98). All-cause mortality was higher with oophorectomy than hysterectomy alone (64.4% vs 35.6%, P<.0001, respectively). Women with concurrent bilateral salpingo-oophorectomy for benign indications had a lower risk of breast cancer than those who had hysterectomy alone. However, all-cause mortality was higher in women with oophorectomy. Perimenopausal patients undergoing hysterectomy for benign indications should be counseled on the risks and benefits of oophorectomy at the time of surgery.

The Structure and Parameterization of the Breast Cancer Transition Model Among Chinese Women

ObjectivesMarkov model simulation based on the natural history of disease is commonly employed for the comparative research of health interventions. The present study aims to simulate the natural progression of breast cancer and parameterize the initial and transition probabilities of multiple states of breast cancer development among Chinese women. MethodsThe age-specific incidence, mortality, and clinical stage distribution of breast cancer; and relapse rate of each clinical stage were collected from China's cancer registry yearbooks and clinical epidemiological studies to simulate the process from full health to breast cancer to death among Chinese women aged 30 to 80 through a Markov cohort study. The validity analysis was conducted to evaluate the accuracy of the model estimation. ResultsA Markov transition model with 7 states (no breast cancer, clinical stages 0-IV breast cancer, and death) was constructed for Chinese women. The age-specific incidence, mortality, and clinical stage distribution of breast cancer estimated by the initial and transition probabilities among different Markov states were highly consistent with the registered data and observed studies. ConclusionA breast cancer transition model for Chinese women has been established with validity. It could be a point of reference for further economic evaluations and breast cancer screening policy formulation.

Estimates of past and future time trends in age-specific breast cancer incidence among women in Karachi, Pakistan: 2004\u20132025

BackgroundThe current demographic trends indicate that breast cancer will pose an even greater public health concern in future for Pakistan. Details on the incidence, disease severity and mortality in respect of breast cancer are limited and without such data, therefore, future health policies or systems in respect of this disease cannot be strategically planned or implemented. The aim of this study was to examine past trends of age-specific breast cancer incidence rates (2004–2015), and to estimate the future volume of breast cancer cases in Karachi through the year 2025.MethodsTwo statistical methods, namely the functional time series models and the log-linear regression model were used; additionally, their real forecasting efficacy in epidemic time series was also evaluated.ResultsIn the past, women aged 60–64 years had the highest overall breast cancer incidence rates, while from 2016 to 2025, large increases in breast cancer rates among women aged 50 to 64 years are expected. The total projected breast cancer incidence will increase by approximately 23.1% in 2020 to 60.7% in 2025. Cases of breast cancer diagnosed in younger women, aged 30–34 years, will increase from 70.7 to 130.6% in 2020 and 2025 relative to 2015.ConclusionsThe breast cancer incidence appeared to have been rising more rapidly among post-menopausal women (aged 55 to 59), while a stable increase in incidence in the youngest age group (15–29 years) of women is expected. The results also infer an expected increase in incidence cases of breast cancer among middle aged women in Karachi, Pakistan. An increase in the number of incident cases of cancer has implications for understanding the health-care needs of growing population and the subsequent demands on health-care system.

Histograms: A Useful Data Analysis Visualization.

Histograms: A Useful Data Analysis Visualization.

Are Global Breast Cancer Incidence and Mortality Patterns Related to Country-Specific Economic Development and Prevention Strategies?

PurposeThere remains considerable international variation in breast cancer incidence and mortality, but a comprehensive examination of rates by country level economic, development and cancer prevention policies is lacking.Materials and MethodsWe compared GLOBOCAN 2012 age-specific breast cancer incidence and mortality rates for 177 countries by using development and policy data available from the WHO Global Cancer Country Profiles data base. We classified each country on the basis of gross national income per capita from the World Development Indicators data base, as follows: low-income country (LIC), lower-middle–income country (LMIC), upper-middle–income country (UMIC), and high-income country (HIC).ResultsThere were 1,651,326 breast cancer cases and 516,868 breast cancer deaths estimated in 2012. Approximately three quarters of all breast cancer cases and 60% of the breast cancer deaths were in women from HICs and UMICs. Age and country-level income explained approximately 60% of the international variation in breast cancer incidence and mortality in women of all ages (adjusted R2 = 58% and 60%, respectively). Economic development indicators additionally increased the overall variation in incidence and mortality by approximately 5%. In women younger than age 50 years, country-level income explained 68% of incidence and 59% of mortality; economic development indicators additionally increased this percentage by approximately 4%. Country-level cancer prevention policy indicators contributed little to explanation of the overall variation in incidence and mortality after analysis accounted for age and country-level income; however, an overall resource summary index of greater economic development and cancer prevention policies was related to lower mortality within each major income level.ConclusionAlthough breast cancer incidence increases with higher income levels in all ages, women in the poorest countries bear a relatively higher burden of breast cancer mortality, particularly women younger than age 50 years.

Obligate Overdiagnosis Due to Mammographic Screening: A Direct Estimate for U.S. Women.

Purpose To determine obligate overdiagnosis rates, defined as the percentage of women diagnosed with screen-detected breast cancer who die of causes other than breast cancer prior to clinical presentation of that cancer, for ductal carcinoma in situ (DCIS), invasive breast cancer, and all breast cancers. Materials and Methods Age-specific all-cause mortality rates from the Human Mortality Database, age-specific breast cancer incidence and mortality rates from Surveillance, Epidemiology, and End Results data, and estimates of mean lead times and lead time distributions from breast cancer screening trials are used to estimate obligate (or type 1) overdiagnosis rates for DCIS, invasive breast cancer, and all breast cancers (DCIS plus invasive) for U.S. women undergoing screening mammography. Mortality rates by age are used to estimate the number of women who die of causes other than breast cancer during the lead time afforded by screening mammography. Resulting age-dependent overdiagnosis rates, along with screen-detected breast cancer incidence by age, are used to estimate type 1 overdiagnosis rates for the U.S. screening population. Results Obligate overdiagnosis rates depend strongly on the age at which a woman is screened, ranging from less than 1% at age 40 years to 30%, 21%, and 22.5% at age 80 years for DCIS, invasive breast cancer, and all breast cancers, respectively. Type 1 overdiagnosis rates among screened women in the United States are estimated to be 9% for DCIS and approximately 7% for both invasive breast cancer and all breast cancers. Screening of women ages 40-49 years (or premenopausal women, as determined from patient history, starting at age 40 years) adds little to obligate overdiagnosis rates (0.15% for DCIS and less than 0.1% for invasive breast cancer and all breast cancers). Conclusion Type 1 overdiagnosis rates increase rapidly with age at screening. Obligate overdiagnosis occurs in 9% of DCIS and approximately 7% of both invasive breast cancer and all breast cancers in the U.S. mammographic screening population, with screening of women ages 40-49 years (or premenopausal women starting at age 40 years) making a negligible contribution of 0.15% to obligate overdiagnosis of DCIS and a contribution of less than 0.1% to the obligate overdiagnosis rates of invasive breast cancer and all breast cancers. © RSNA, 2017 Online supplemental material is available for this article.

Incidence of breast cancer in Chinese women exposed to the 1959\u20131961 great Chinese famine

BackgroundThe association of malnutrition in early life with breast cancer risk has been studied in Europe by investigating survivors of the Dutch Hunger Winter Famine, but not in China. We evaluated the effect of exposure to the 1959–1961 Great Leap Forward famine on subsequent breast cancer risk in Chinese women.MethodsA total of 59,060 women born in 1955~1966 were recruited from Minhang district, Shanghai, China, during the period 2008 to 2012. A baseline survey was conducted to collect demographic characteristics and known risk factors for breast cancer. Incident breast cancers were identified by conducting record linkage with the Shanghai Cancer Registry up to June 30, 2015, and confirmed through medical records. Cumulative probabilities of cancer incidence were evaluated after adjusting for age, educational level and other confounders. Cox regression models were applied to estimate the hazard ratios (HR) and 95% confidence intervals (CI) of breast cancer.ResultsThe overall crude incidence of in situ and invasive breast cancer were 19.2 and 115.0 per 100,000, respectively, in women conceived or born during the famine (1959–1962), slightly higher than those in women born before (1955–1958) (13.2 and 109.8/100,000) and after (1963–1966) (10.4 and 101.5/100,000). Particularly, at age group of 50–52 years when all participants contributed person-year of observations, the age-specific incidence of invasive breast cancer was higher in pre-natal exposed women (123.7/100,000, 95%CI: 94.5–161.9/100,000) than in post-natal exposed (109.6/100,000, 95%CI: 69.1–174.0/100,000) and unexposed women (82.7/100,000, 95%CI: 46.9–145.7/100,000). However, the incidence of cancer in situ was slightly lower in pre-natal exposed women at the age group. Adjusted cumulative probabilities of breast cancer incidence, both in-situ and invasive, were also observed to be higher in women exposed to the famine, however, the difference was not statistically significant.ConclusionOur results suggest a possible adverse, but limited, impact of exposure to the Great famine on the risk of breast cancer in Chinese women.

Predicting Breast Cancer Incidence Rates Among White and Black Women in the United States: An Application of FTS Model

Development of statistical model for cancer incidence trend predictions can provide a sound and accurate foundation for planning a comprehensive national strategy for optimal partitioning of research resources. Several studies in the past showed that that there are racial/ethnic disparities exist between breast cancer incidence rates among black and white women in the United States. Some of the studies also showed that the disparity in breast cancer incidence rates among white and black US women is widening, with relatively higher incidence rates among black women. In this paper, we apply functional time series (FTS) models on the age-specific breast cancer incidence rates for these two major groups of women in US, and forecast their age-incidence curves. The data are obtained from the Surveillance, Epidemiology and End Results (SEER) program of the United States. We use annual unadjusted breast cancer incidence rates from 1973 to 2013 in 5-year agegroups (15-19, 20-24, 25-29, 30-34, 35-39, 40-44, 45–49, 50–54, 55–59, 60–64, 65–69, 70–74, 75–79, 80–84 and 85+). Age-specific cancer incidence curves are obtained using nonparametric smoothing methods. The curves are then decomposed using functional data paradigm and we fit functional time series (FTS) models for each population of women separately. The smoothed incidence curves are then forecasted and prediction intervals are calculated. Fifteen-year forecasts indicate an overall increase in future breast cancer incidence rates for both groups of women. This increase appears to be faster among black women and relatively slower among the whites. The projections suggest a need for equal delivery of quality care to eliminate breast cancer disparities among the two major groups of women in US.

The Development of Breast Cancer Screening in Qatar (January 2008 – April 2015)

Qatar has one of the highest age-adjusted breast cancer incidences in the Arab world. Although this is much lower than the incidence in the West. Breast cancer incidence in Qatar was 45 per 100,000 in 2003-2007. 53 per 100,000 in 2008-2011. These higher incidence rates in Qatar are mainly due to the growing population. The prevalent age group, between both Qatari and non-Qatari patients, was 40-50 years old. This suggests that the age-specific incidence of breast cancer in Qatari women is shifting more to a pattern usually not seen in Western nations where median age at diagnosis is 61 years of age, moreover the diagnosis is often at advanced stages of breast cancer. These factors, together with reconfirmed evidence of mortality benefit from breast cancer screening trials, led to establishment the first hospital based mammographic breast cancer screening program in Qatar. It uses a distributed model of mammography service. The program accepts eligible asymptomatic women at age between 40-69 years and was launched in 2008. It adopted international standards of breast screening practice and breast cancer detection.