Breast Cancer Incidence Trends Research Articles

Abstract PO5-09-12: Unraveling the Intricacies of Racial Disparities in Breast Cancer in Brazil

Abstract Abstract Background: Over the past three decades, numerous countries have experienced a substantial decrease in breast cancer (BC) fatality, attributed to heightened consciousness, widened and earlier screening, and enhanced therapeutic interventions. However, these advancements have not eradicated the disparity in BC treatment across different racial and ethnic groups. In Brazil, the causes of these disparities are diverse and intricate, resembling health inequalities among ethnic communities observed in other countries. This study aimed to investigate the trends in BC incidence and mortality rates in Brazil, considering clinicopathological and sociodemographic variations, and placing particular emphasis on the severity of racial disparity concerning race/skin color. Patients and methods: Incidence trends for women with BC were analyzed using data from 13 Brazilian Population-Based Cancer Registries covering the period 2010-2015. Crude incidence ratios (CIRs) and the annual average percent change (AAPC) were calculated. Clinical and sociodemographic information from 348 Hospital-Based Cancer Registries spanning from 2000 to 2019 was also utilized. Meanwhile, mortality data for the years 2000-2020 were obtained from the National Mortality Information System. Racial and skin color data were collected through a self-declaration process, following the classification proposed by the Brazilian Institute of Geography and Statistics, which included categories such as white, black, and brown/mixed race. In the analysis, black and brown/mixed race categories were combined as black. Yellow and indigenous categories were excluded. Statistical significance was defined as a p-value less than 0.05. To determine clinically relevant differences, a threshold of more than 5% disparity in proportional values was used as an arbitrary criterion. Results: Between 2010 and 2015, a total of 70,896 newly diagnosed cases of BC were recorded. Mean CIRs were 83.9/100,000 for the overall population, 101.3/100,000 for white women, and 59.7/100,000 for black women. Neither the group of white women (AAPC -1.7; 95% CI: -7.9 to 4.9; p = 0.506) nor the group of black women (AAPC -0.4; 95% CI: -5.0 to 4.5; p = 0.831) exhibited any significant changes in the incidence rate. Black women predominantly originated from underdeveloped regions (56.4%, p < 0.001), were referred by the public healthcare system in Brazil (79.0%, p < 0.001), had ≤ 8 years of schooling (68.7%, p < 0.001), were unmarried (50.9%, p< 0.001), reported alcohol consumption (20.9%, p < 0.001), and were diagnosed with advanced stage disease (60.1%, p < 0.001). The escalation in mortality rates among black women exhibited a notable difference, amounting to 3.8 times the increase observed among white women (AAPC + 2.3; 95% CI: 2.1 to 2.5; p < 0.001) (AAPC + 0.6; 95% CI: 0.5 to 0.7; p < 0.001). Conclusion: Despite the lower incidence of BC in black women compared to their white counterparts, there is a concerning rise in BC-related mortality rates among black women. This group exhibits a significantly unfavorable sociodemographic and clinicopathological profile. These results highlight the pressing need to address the multifaceted factors contributing to these disparities, encompassing socioeconomic disparities and unequal healthcare access. Keywords: Breast cancer; racial disparities; incidence; mortality. Citation Format: Jesse Lopes da Silva, Andreia Cristina De Melo, Mariana Espirito Santo Rodrigues, Lucas Zanetti de Albuquerque, Luiz Claudio Santos Thuler. Unraveling the Intricacies of Racial Disparities in Breast Cancer in Brazil [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO5-09-12.

Abstract 4854: Breast cancer incidence trends in Ukraine 2010-2019: Rising incidence at young ages

Abstract Background. BC commonly affects women of older age, however, in developing countries around 20-25% cases of BC presented in young woman. Age-specific clinical characteristics or outcomes data for young women are lacking. Most of the standard treatments used in this subpopulation currently are derived from older patients. Early onset BC is often defined aggressive in nature. Several research have attributed this to a hidden unique biology. However, findings remain controversial. Purpose: The aim of this study is to describe recent trends for BC incidence in Ukraine since 2010 by age groups and interpret them to seek clue for improvement. Methods: We analyzed records from the NCR on 143420 BC cases (C50, International Statistical Classification of Diseases and Related Health Problems, 10th Revision (ICD-10)) diagnosed in 2010-2019 in female Ukrainian population. The data were submitted on the beginning of 2022. We calculated annual age-standardized incidence rates (ASRWs) for three age groups. The estimated annual percent change (EAPC) of the rates was calculated using the generalized linear regression. The difference of the rates with its statistical significance was determined with the standardized rate ratio. Results: During 2010-2019, the proportion of BC in all cancers detected at the age of 20-44 increased from 21.7% to 25.9%, while the frequency of BC detection at the age of 45+ did not change and ranged 19.3-20.2%. During the study period, the BC incidence rate has increased significantly (≤0.01): the ASRW of females aged 0-85+ grew with EAPC=0.6% amounting to 42.4-45.7 per 100,000 population, the incidence rate of women aged 45+ grew with EAPC=0.3% ranging from 130.0 to 139.6 per 100,000 population, while the incidence rate of women aged 20-44 grew with EAPC=1.8% amounting to 22.8-27.8 per 100,000 population. In age group 20-44 years, EAPC of BC incidence (1.8%) significantly exceeds the EAPC of the incidence for all cancers combined (0.2%). The dynamics of stage distribution showed increasing proportion of BC cases detected in women aged 20-44 in stage 1 (by 4.1% from 2010 to 2019) and its decreasing for BC cases detected in stage 2 by 4.5%; the proportion of cases diagnosed in stage 4 decreased by 0.5% along with increase in number of cases with undefined stage by 0.6%. Conclusions: The obtained results indicate trends for increasing the incidence of Early Onset BC in Ukraine and justify need for the further research elucidating prognosis and validating novel biomarkers for customizing therapy for this patient group . Citation Format: Nataliia Verovkina, Olena Sumkina, Liubov Syvak, Wafik El-Diery. Breast cancer incidence trends in Ukraine 2010-2019: Rising incidence at young ages [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4854.

Time Trends in Male Breast Cancer Incidence, Mortality, and Survival in Austria (1983-2017).

Male breast cancer (MBC) comprises less than 1% of all breast cancer cases globally and remains understudied with persisting sex-specific survival disadvantages. We aim to contribute to better understanding of MBC with a comprehensive analysis of time-trends over several decades in Austria. We used Austrian National Cancer Registry data on 1648 cases of MBC cases diagnosed between 1983 and 2017 in Austria. Overall incidence, mortality, and survival rates, as well as age-, stage-, and period-specific incidence and survival rates were calculated. Joinpoint regression was performed to assess trends. MBC incidence rates increased throughout the whole observation period (1983-2017) with an annual percent change (APC) of 1.44% (95% confidence interval, CI: 0.77 to 2.11). During the same period, morality rates were stable (APC: -0.25, 95% CI: -0.53 to 0.60). Ten-year survival rates showed three phases of decreasing increases with an average APC of 2.45%, 1983-2009 (95% CI: 2.1 to 2.74). Five-year survival rates improved until 2000 (APC: 2.31, 95% CI: 1.34 to 3.30) and remained stable thereafter (APC: 0.10, 95% CI: -0.61 to 0.80). Stage-specific analyses showed a single trend of stable incidence rates of distant disease MBC (APC: -0.03, 95% CI: -1.67 to 1.65). Further, we observed increases in localised, regional, and unknown stage cancer incidence and increases in incidence rates across all age groups over the whole observation period. However, the estimates on these subgroup-specific trends (according to age- and stage) show wider 95% CIs and lower bounds closer to zero or negative in comparison to our findings on overall incidence, mortality, and survival. Despite improvements in survival rates, MBC mortality rates remained largely stable between 1983 and 2017 in Austria, possibly resulting from a balance between increasing overall incidence and stable incidence rates of distant disease MBC.

Breast cancer incidence trends in Golestan, Iran: An age-period-cohort analysis by ethnic region, 2004-2018

BackgroundWe aimed to examine the effects of age, diagnosis year (calendar period) and birth year (cohort) on the incidence trends of breast cancer among Golestan women, Northeast Iran, 2004–2018. MethodsIncidence data were obtained by residential status (urban/rural) and ethnic region (Turkmens/non-Turkmens). We calculated age-standardized incidence rates (ASRs) per 100,000 person-years. The estimated annual percentage change (EAPC) were calculated, and age-period-cohort (APC) models fitted to assess non-linear effects of period and cohort as incidence rate ratios (IRRs). ResultsThe total number of female breast cancer cases in Golestan, 2004–2018, were 3853, with an overall ASR of 31.3. We found higher rates in urban population (40.5) and non-Turkmens region (38.5) compared to rural area (20.8) and Turkmens region (20.2), respectively. There were increasing trends in incidence rates overall (EAPC= 4.4; 95%CI: 2.2, 6.7), with greater changes in rural areas (EAPC=5.1), particularly among non-Turkmens (EAPC=5.8). The results of the APC analysis indicate the presence of significant non-linear cohort effects with increasing IRRs across successive birth cohorts (IRR=0.1 and IRR= 2.6 for the oldest and the youngest birth cohorts vs. the reference birth cohort, respectively). ConclusionWe found increasing trends in breast cancer incidence among Golestan women over the study period, with disparities in patterns and trends by residence area and ethnic region. The observed cohort effects suggest an increasing prevalence of key risk factors for breast cancer in this Iranian population. Further investigations are warranted to clarify the relationships between determinants such as reproductive factors and ethnicity in the region.

Epidemiology of Breast, Corpus Uteri, and Ovarian Cancers in Lebanon With Emphasis on Breast Cancer Incidence Trends and Risk Factors Compared to Regional and Global Rates.

This study explores the incidence and trends of breast (Bca), corpus uteri (CUca), and ovarian (Oca) cancer in Lebanon, a Middle Eastern country. It compares the Bca rates to regional and global ones and discusses Bca risk factors in Lebanon. Globally, Bca is the premier cause of cancer morbidity and mortality in women. Data on female Bca, CUca, and Oca published by the Lebanese national cancer registry were obtained (ie, for the years of 2005 to 2016). The age-standardized incidence rates (ASIRw) and age-specific rates per 100,000 female population were computed. From 2005 to 2016, Bca, Oca, and CUca ranked first, sixth, and seventh, respectively, for cancer incidence among women in Lebanon. Bca alone accounted for 39.4% of all new female cancer cases. The ASIRw increased significantly for Bca and CUca (APC: 3.60 and 3.73, P < .05) but not for Oca (APC: 1.27, P > .05). The Bca ASIRw (per 100,000) increased significantly from 71.0 in 2005 to 115.6 in 2013 (P < .05), then decreased steadily but non-significantly to reach 96.8 in 2016 (P > .05). Lebanon's Bca ASIRw is comparable to developed countries. This may reflect altered sociological and reproductive patterns as the country transitions from regional to global trends. The five-year age-specific rates analysis revealed that Bca rates rose steeply from 35-39 to 50-54, dropped slightly between 55 and 64, then rose till 75+. The five-year age-specific rates between 35 and 54 among Lebanese women were amongst the highest worldwide from 2008 to 2012, even higher than the rates in Belgium, which had the highest ASIRw of Bca worldwide in 2020. Lebanon's Bca ASIRw is among the highest globally. It's important to investigate the contributing factors and develop a national Bca control strategy. This study supports the national recommendation in initiating Bca screening at age 40 for women.

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.

Investigating the trends of incidence rates of breast cancer in Southern Iran: a population based survey

BackgroundThe overall incidence of breast cancer is different all over the world and even within a nation. The present study aims to investigate the stratum-specific incidence trends of breast cancer in southern Iran.MethodsIn this retrospective cohort study, the data of Fars Population-Based Cancer Registry was used during 2001–2018. New cancer cases with ICD-O-3 codes C50.0 to C50.9 were categorized based on age group, morphology, and topography. Age-specific incidence rates of breast cancer were calculated during 2001–2018. Annual overall and truncated age-standardized incidence rates and their 95% Confidence Intervals (CIs) were also calculated. Afterward, the Annual Percentage Changes (APCs) of the age-specific and age-standardized incidence rates of breast cancer during 2001–2018 were calculated using Joinpoint regression software.ResultsAn increasing trend was observed in the incidence of breast cancer among women during 2001–2018 (APC of age-standardized incidence rates: 9.5 (95% CI: 7.5, 11.5)).However, the trend was increasing less during the recent years. The APC of age-standardized rates decreased from 15.03 (95% CI: 10.4, 19.8) in 2007 to 6.15(95% CI: 4.0, 8.4) in 2018. The most common morphology of breast cancer was invasive ductal carcinoma (77.3% in females and 75.1% in males) and its trend was similar to the general trend of different types of breast cancer. The most common site of breast cancer was the upper outer quadrant. Most breast cancer cases were female and males accounted for 2.45% of the cases. Among females, 40–55 was the most prevalent age group.ConclusionThe incidence of breast cancer among women living in southern Iran showed an increasing trend from 2001 to 2018. However, the rate of increase exhibited a milder slope during the more recent years. Based on the higher prevalence of breast cancer in the 40–55 age group observed in the present study, it offers valuable insight into the potential reduction of the breast cancer screening age from 50 to 40 years for healthy Iranian women. However, before implementing such a policy change, it is crucial to conduct additional studies that specifically examine the cost-effectiveness, as well as the potential benefits and risks associated with this alteration.

Recent trends in hereditary breast cancer incidence by race and age in KwaZulu-Natal, South Africa: An 11-year single-centre retrospective study (2011-2021).

Breast cancer incidence has increased globally in the last decade, especially in low- and middle-income countries. In Sub-Saharan Africa, breast cancer trends have been described only in a few populations owing to the scarcity of population-specific data. Using data collected between 2011 and 2021 at Inkosi Albert Luthuli Central Hospital, this retrospective study describes demographic and genetic trends for hereditary breast cancer patients in the KwaZulu-Natal province, South Africa. Six hundred and forty-five patients were included, of whom 44.3% were Black, 36.8% Indian, 15.6% White and 3.2% Coloured. The number of annual new cases increased from eight in 2011 to 145 in 2021, with a notable increase among Blacks. The mean onset age was 46 years, and Black patients were diagnosed ~10 years earlier than White and Indian patients. Triple-negative breast cancers accounted for 20.3% of hereditary cases, and 51.1% of them were Black. Bilateral and recurrent breast cancers constituted 7.4%, while pathogenic sequence variants in BRCA1/2 were reported in 10.4% of all patients, and the majority were Blacks and Indians. Overall, the KwaZulu-Natal province has seen an increase in hereditary breast cancer incidence in the past decade. Despite testing negative for pathogenic sequence variants, Black women frequently presented with breast cancers that are BRCA1-like, while Indians presented with extensive family history. This suggests that South African patients may require unique approaches to interventions, such as early detection and awareness programs among Blacks and increased genetic screening among Indians.

Breast cancer incidence in Yogyakarta, Indonesia from 2008-2019: A cross-sectional study using trend analysis and geographical information system.

Breast cancer is a significant public health concern worldwide, including in Indonesia. Little is known about the spatial and temporal patterns of breast cancer incidence in Indonesia. This study aimed to analyze temporal and spatial variations of breast cancer incidence in Yogyakarta Province, Indonesia. The study used breast cancer case data from the Yogyakarta Population-Based Cancer Registry (PBCR) from 2008 to 2019. The catchment areas of the PBCR included the 48 subdistricts of 3 districts (Sleman, Yogyakarta City, and Bantul). Age-standardized incidence rates (ASR) were calculated for each subdistrict. Joinpoint regression was used to detect any significant changes in trends over time. Global Moran's and Local Indicators of Spatial Association (LISA) analyses were performed to identify any spatial clusters or outliers. The subdistricts had a median ASR of 41.9, with a range of 15.3-70.4. The majority of cases were diagnosed at a late stage, with Yogyakarta City having the highest proportion of diagnoses at stage 4. The study observed a significant increasing trend in breast cancer incidence over the study period the fastest of which is in Yogyakarta City with an average annual percentage change of 18.77%, with Sleman having an 18.21% and Bantul having 8.94% average changes each year (p <0.05). We also found a significant positive spatial autocorrelation of breast cancer incidence rates in the province (I = 0.581, p <0.001). LISA analysis identified 11 subdistricts which were high-high clusters in the central area of Yogyakarta City and six low-low clusters in the southeast region of the catchment area in the Bantul and Sleman Districts. No spatial outliers were identified. We found significant spatial clustering of BC ASR in the Yogyakarta Province, and there was a trend of increasing ASR across the region. These findings can inform resource allocation for public health efforts to high-risk areas and develop targeted prevention and early detection strategies. Further res is needed to understand the factors driving the observed temporal and spatial patterns of breast cancer incidence in Yogyakarta Province, Indonesia.

Temporal Pattern and Age-Period-Cohort Analysis of Breast Cancer Incidence in Iranian Women (2009-2017).

Breast cancer accounted for 28.1% of all female cancers in 2020 in Iran. This study was conducted to evaluate the time trend of breast cancer incidence and to identify the changes of breast cancer incidence in age, period, and birth cohorts in Iran, in the 2009-2017 timeframe. Annual cancer statistics for female breast cancer were obtained from the Iranian National Population-based Cancer Registry (INPCR) database from 2009 to 2017. The age-period-cohort (APC) analysis was used to evaluate the time trend of breast cancer incidence in age, period and birth cohorts between 2009 and 2017. R package (Epi) was used to analyze data. Results were considered statistically significant at P<0.05. The age effect showed an increased incidence of breast cancer until the age of 45, and after this age the speed of increase was slower until 65 years. There was an increased diagnosis in 2015-2017 (period effect) for many age groups, especially in the 70- and over 80-year-old group. Our findings indicated that breast cancer incidence peaks in the age of 45 in Iranian women, which is a decade earlier compared to the Western world. The period effect in 2015-2017 can be explained by the fact that in 2014, the former Iranian pathology-based cancer registry was upgraded to a population-based cancer registry, which resulted in improved coverage of cancer registry and case finding.

Trends in Breast Cancer Incidence and Mortality in the United States From 2004-2018: A Surveillance, Epidemiology, and End Results (SEER)-Based Study.

The incidence and mortality data for patients with breast cancer in the United States are important to healthcare administrators for planning healthcare measures such as screening mammograms. In this study, we examined breast cancer incidence and incidence-based mortality in the United States from 2004-2018 using the Surveillance, Epidemiology, and End Results (SEER) database. We reviewed 915,417 cases of breast cancer diagnosed between 2004 and 2018. Overall, the data showed an increased incidence rate of breast cancer among all races and a decreased mortality rate among all races. Breast cancer incidence rates increasedby 0.3% (95% CI, 0.1, 0.4, p<0.001) per year over the study period.Breast cancer incidence rates increased for all age, race, and stage groups except for stage regional, which showed a statistically significant decrease in the incidence of -0.9% (95% CI, -1.1, -0.7, p<0.001).The highest decrease in mortality was observed among white patients, withan overall statistically significant decrease in rates by -14.3% (95% CI, -18.1,-10.4, p<0.001). The highest decrease in rates was observed between 2016 and 2018: -48.6 (95% CI, -52.6,-44.3, p<0.001). In black/African American patients, the overall incidence-based mortality decreased by -11.6% (95% CI -15.9, -7.1 p<.001), with the highest decrease in rates observed between 2016 and 2018 with a decrease of -51.3% (95% CI -56.6, -45.3, p<0.001). In Hispanic Americans, the overall incidence-based mortality decreased by -12.3% (95% CI -16.9, -7.4, p<.001), which is lower than in white Americans.

Analysis on Incidence and Mortality Trends and Age–Period–Cohort of Breast Cancer in Chinese Women from 1990 to 2019

To analyze the incidence and mortality trends of breast cancer among women in China from 1990 to 2019 and explore the effects of age, period, and cohort on the incidence and mortality of breast cancer. We performed a Joinpoint regression model to describe trends in breast cancer incidence and mortality. We used an age-period-cohort analysis model to estimate the impact of age, period, and cohort on breast cancer incidence and mortality. We collected breast cancer incidence and mortality among women aged 20-89 in China (1990-2019) from the Global Health Data Exchange (GHDx) database. The crude incidence and mortality of breast cancer from 1990 to 2019 in Chinese women showed an increasing trend, with an average annual increase percentage (AAPC) of 4.69% and 2.18%, respectively. The analysis on the age-period-cohort model revealed that the risk of incidence increased first and then decreased with age and peaked at 55-59 years old, whereas the risk of mortality increased by approximately 60.34 times from 20 to 89 years old. The risk of incidence and mortality increased by 2.64 and 1.49 times with the passage of time, respectively. The later the birth cohort is, the lower the risk of incidence and mortality will be. From 1990 to 2019, the incidence and mortality of breast cancer among Chinese women showed an increasing trend, and the prevention and control situation of breast cancer was still grim. Therefore, visual examination and palpation examination should be actively carried out in adult women with breast cancer, and the conventional population after 40 years of age, the high-risk population carrying hereditary breast cancer gene and the elderly population should be assisted with imaging examination along with palpation examination. When treating patients suffering from breast cancer, in order to reduce the death rate, a personalized treatment plan should be developed based on the characteristics of different patients.

Trends in Incidence Rates, Mortality Rates, and Age-Period-Cohort Effects of Female Breast Cancer - China, 2003-2017.

This study reported the trends in female breast cancer incidence and mortality rates in China, and analyzed the corresponding age-period-cohort effects. Data from 22 population-based cancer registries in China between 2003 and 2017 were analyzed. Age-standardized incidence rates (ASIR) and mortality rates (ASMR) were calculated using Segi's world standard population. Joinpoint regression was employed to evaluate trends, and age-period-cohort effects were examined using the intrinsic estimator method. The ASIR for female breast cancer exhibited a more rapid increase in rural areas compared to urban areas across all age groups. The most substantial increase was observed in the 20-34 age group in rural areas [annual percent change (APC)=9.0%, 95% confidence interval (CI): 7.0%-11.0%, P<0.001]. The ASMR for females under 50 years old remained stable from 2003 to 2017 in both urban and rural areas. However, the ASMR for females over 50 in rural areas and those over 65 in urban areas demonstrated a significant increase, with the most pronounced increase observed among females over 65 in rural areas (APC=4.9%, 95% CI: 2.8%-7.0%, P<0.001). Age-period-cohort analysis revealed increasing period effects and decreasing cohort effects for female breast cancer incidence and mortality rates in both urban and rural settings. Notably, the cohort effect for incidence displayed a slight upward trend for females born between 1983 and 1992 in rural areas. Our study revealed a rapid increase in breast cancer incidence among younger generations and an accelerated mortality rate in older populations residing in rural areas. To effectively address the growing burden of female breast cancer in China, it is essential to develop and implement targeted intervention strategies.

Long term trends of breast cancer incidence according to proliferation status

BackgroundLong-term breast cancer incidence trends according to proliferation status are poorly described. We studied time-trends in breast cancer incidence, using mitotic count and Ki-67 as markers of proliferation.MethodsAmong 83,298 Norwegian women followed for breast cancer occurrence 1961–2012, 2995 incident breast cancers were diagnosed. Ki-67 was assessed using immunohistochemistry on tissue microarrays and mitoses were counted on whole sections. We compared incidence rates according to proliferation status among women born 1886–1928 and 1929–1977, estimating age-specific incidence rate ratios. We performed multiple imputations to account for unknown proliferation status. Mean values of Ki-67 and mitotic counts were calculated, according to age and birth year. We performed separate incidence analyses for HER2+ and triple negative breast cancers.ResultsAmong women aged 40–69 years, incidence rates of tumours with low-proliferative activity were higher among those born in 1929 or later, compared to before 1929, according to Ki-67 and mitotic count. Incidence rates of tumours with high-proliferative activity were also higher in women born in 1929 or later compared to before 1929 according to Ki-67, but not according to mitotic count. Mean values of Ki-67 and mitotic count varied according to age and birth year. In subtype-specific analyses we found an increase of high-proliferative HER2+ tumours according to Ki-67 in women born in 1929 or later, compared to before 1929.ConclusionsThere has been a temporal increase in both low- and high-proliferative breast cancers.

Characteristics and chronologically changing patterns of late-onset breast cancer in Korean women of age ≥ 70 years: A hospital based-registry study

BackgroundWomen from Asian and western countries have vastly different ages of onset of breast cancer, with the disease tending to occur at an older age in the West. Through an investigation of the patterns of old-onset breast cancer (OBC) in Korean women, we aimed to identify the characteristics of Korean OBC and evaluate whether these patterns are changing in relation to increasing westernization.MethodsThis study retrospectively evaluated 102,379 patients who underwent surgical treatment of primary breast cancer between January 1, 2000 and December 31, 2013 in Korea. We used hospital -based breast cancer registry and analyzed data from these patients using multiple linear regression analysis to compare the characteristics and chronologically changing patterns between OBC (70 years of age or older) and non-OBC (40–69 years of age) patients in Korea.ResultsA total of 6% of the 102,379 patients had OBC. Overall, OBC had more favorable biological features, such as a higher incidence of luminal A subtype, than did non-OBC, except for a higher incidence rate of triple-negative breast cancer (TNBC). However, OBC also presented with a higher overall disease stage, including higher T and M stages. Although the incidence rates of both OBC and non-OBC have increased overtime, the relative proportion of OBC patients has slightly increased, whereas that of non-OBC has slightly decreased. The increase in the incidence of both OBC and non-OBC was primarily due to the luminal A subtype.ConclusionsBased on a hospital-based registry, overall, Korean OBC had favorable biological features but showed a higher rate of TNBC and advanced cancer stages. The incidence trend of breast cancer in Korea is slowly shifting toward an older age at onset, largely due to the luminal A subtype. Our results may provide novel insights into OBC in Asia, and aid in the development of optimal management of the disease in Asia.Trial registrationRetrospectively registered.

Breast Cancer Incidence Patterns in the Saudi Female Population: A 17-Year Retrospective Analysis.

Background and Objectives: Breast cancer is considered the most commonly diagnosed type of cancer among women globally and in Saudi Arabia. This study aimed to assess breast cancer incidence patterns and trends among the Saudi female population. Materials and Methods: Breast cancer incidence parameters were obtained from the Saudi Cancer Registry (SCR). The data were retrospectively analyzed for the period from 2001 to 2017 to investigate changes in incidence rates. Temporal trends were also analyzed through joinpoint regression analysis and were dissected by age groups and administrative regions. Results: During the specified period, breast cancer jumped by 55% to constitute 30.9% of all cancer cases among Saudi females. The median age at diagnosis increased to reach 51 years at the end of that period, with an overall increase of 6.3%. The overall Age-Standardized Incidence Rate (ASR) escalated by 151.7% from 11.8/100,000 to 29.7/100,000 population for that period. The Eastern region noticeably had the highest ASR and peaked at 52.2/100,000 population. The joinpoint analysis of the ASR showed increased trends, with an annual percent change (APC) of 5.13% (p &lt; 0.05, [95% CI 4-6.3]). An age-specific analysis was also performed and showed that the age group 70-74 years had the highest trend (APC 10.2%, [95% CI 7.2-13.4], p &lt; 0.05). Region-specific analysis revealed that the Jouf region had the highest trend among the regions (APC 8.8%, [95% CI 3.7-14.2], p &lt; 0.05). Conclusions: Our analysis indicates increased breast cancer incidence in Saudi Arabia with an alarming pace. With the existing trend, it is expected that Saudi Arabia will continue to display an increase in breast cancer incidence. Long-term preventive measures and more effective screening strategies are warranted to alleviate the burden of the disease.

Cancer survival in Thailand from 1997 to 2012: Assessing the impact of universal health coverage

BackgroundIn recent decades, many countries worldwide have implemented some form of Universal Health Coverage (UHC). We sought to evaluate incidence and survival trends of breast, cervical, and colorectal cancer before and after the implementation of UHC in Thailand. MethodsThe age-standardized incidence rate and 1- and 5-year net survival (NS) were calculated for five Thai provinces, namely Bangkok, Chiang Mai, Khon Kaen, Lampang, and Songkhla for breast, cervix, and colorectal cancer in three study periods (1997–2012): before, during, and after the implementation of UHC. ResultsThe incidence of breast and colorectal cancer has increased over time, while the incidence of cervical cancer has decreased (17.9–29.9, 9.0–13.6, and 19.6–12.3 per 100,000, respectively). Larger proportion of breast cancer were diagnosed with localized stage after UHC implementation compared to the period prior to UHC (31.5 % vs 19.0 %). Overall, The improvement in survival by cancer site varied in magnitude with a 5-year NS increase from 61.3 % to 75.1 % for breast, 55.4–59.5 % for cervical, and 39.9–47.6 % for colorectal cancer. The amount of increase slightly differed across provinces. ConclusionRising incidence for breast and colorectal, and declining cervical cancer may partly be attributable to improved awareness and early detection programs. Additionally, improvement in survival may partly be attributable to increased access to healthcare, availability of treatment, and increased access to cancer screening after UHC was implemented. Thus, continued expansion of UHC package on cancer could potentially contribute to further improvement of cancer control in Thailand. Policy summaryThis study provides important evidence on the impact of UHC in cancer burden and survival for breast, cervical, and colorectal cancer in Thailand. This study serves as an example for other countries where UHC has been recently implemented and guide policymakers in allocating resources towards UHC and cancer control programs.

Evaluation of Breast Cancer Incidence Trends in the Karaganda Region of Kazakhstan.

The study conducted a component analysis of the dynamics of the incidence of breast cancer (BC) in Karaganda region. Primary data were for registered patients with BC (ICD 10-C50) in Kazakhstan, Karaganda region the period of 2009-2018. Evaluation of changes in BC incidence in the population of Karaganda was performed using component analysis according to the methodological recommendations. Overall, 4,391 new cases of BC and 1,202 deaths were recorded. The incidence rate increased from 44.4 (2009) to 72.7 in 2018 and the overall growth was 28.37 per 100,000 population of female, including due to the age structure - ∑ΔA =3.13, due to the risk of acquiring illness - ∑ΔR =22.69 and their combined effect - ∑ΔRA =2.56. The component analysis revealed that the increase in the number of patients with BC was mainly due to the growth of the population (ΔP =+3.7%), changes in its age structure (ΔA =+10.3%) and changes associated with the risk of acquiring illness (ΔR =+75.0%). The mortality rate in the region changed from 18.6 (2009) to 10.9 (2018) and tended to decrease. The role of the influence of demographic factors and the risk of acquiring illness on the formation of the number of patients and the incidence of BC was evaluated. In this region, these indicators were the highest. The implementation of the results of this study is recommended in management of anticancer activities for BC.

Forecast of a future leveling of the incidence trends of female breast cancer in Taiwan: an age-period-cohort analysis

Breast cancer is the most common cancer among women in Taiwan. The age-standardized incidence rate has doubled in just 20 years, causing considerable concern to health professionals and the general public. This study used an ensemble of age-period-cohort models to estimate breast cancer incidence trends in Taiwan from 1997 to 2016 and project trends up to 2035. The (truncated) world standard population (World Health Organization 2000) proportions (age groups: 25–29, 30–34, …, 80–84, and older than 85 years) were used to calculate age-standardized incidence rates. The age-standardized incidence rate from 1997 (60.33/100,000 population) to 2016 (128.20/100,000 population) increased rapidly. The projection is that the increase in the age-standardized incidence will subsequently slow and exhibit a plateau in 2031 (151.32/100,000 population). From 2026 to 2035, the age-specific incidence rates for women older than 55 years old (postmenopausal breast cancer) are projected to increase with larger percentage increments for older women. A future leveling of female breast cancer incidence trends in Taiwan is anticipated. The majority of the patients with breast cancer in the future will be women aged 55 years and older. Education on lifestyle recommendations and mammography screening is required to reduce the burden of breast cancer. The results should have implications for other countries which are also confronted with the same public health problem of rapidly increasing breast cancer incidences.

Trend of Breast Cancer Incidence in Iran During A Fifteen-Year Interval According To National Cancer Registry Reports

Trend of Breast Cancer Incidence in Iran During A Fifteen-Year Interval According To National Cancer Registry Reports