[Show abstract][Hide abstract]ABSTRACT: Breast cancer mortality is declining in many Western countries. If mammography screening contributed to decreases in mortality, then decreases in advanced breast cancer incidence should also be noticeable.
We assessed incidence trends of advanced breast cancer in areas where mammography screening is practiced for at least 7 years with 60% minimum participation and where population-based registration of advanced breast cancer existed. Through a systematic Medline search, we identified relevant published data for Australia, Italy, Norway, Switzerland, The Netherlands, U.K. and the U.S.A. Data from cancer registries in Northern Ireland, Scotland, the U.S.A. (Surveillance, Epidemiology and End Results (SEER), and Connecticut), and Tasmania (Australia) were available for the study. Criterion for advanced cancer was the tumour size, and if not available, spread to regional/distant sites.
Age-adjusted annual percent changes (APCs) were stable or increasing in ten areas (APCs of -0.5% to 1.7%). In four areas (Firenze, the Netherlands, SEER and Connecticut) there were transient downward trends followed by increases back to pre-screening rates.
In areas with widespread sustained mammographic screening, trends in advanced breast cancer incidence do not support a substantial role for screening in the decrease in mortality.
Full-text · Article · Jul 2011 · Annals of Oncology
[Show abstract][Hide abstract]ABSTRACT: Incidence of breast cancer is rising in Asian countries, and breast cancer is the most common cancer among Asian women. However, there are few recent descriptive reports on the epidemiology of breast cancer among Eastern and Southeastern Asian populations.
We examined incidence trends for invasive breast cancer in women aged ≥20 years from 15 registries in Eastern (China, Japan, the Republic of Korea, Taiwan) and Southeastern Asia (the Philippines, Singapore, Thailand) for the period 1993-2002 mainly using data from Cancer Incidence in Five Continents, Volumes VIII and IX. We compared trends in annual incidence rates and age-specific incidence curves over a 10-year period. We also compared the incidence rates of Asian-Americans with the rates of their Asian counterparts.
Breast cancer incidence rates increased gradually over time in all study populations. Rates were relatively high in Southeastern Asia and became progressively lower along a south-to-north gradient, with a fourfold geographic variation within the study populations. Age-specific incidence curves showed patterns that gradually changed according to incidence rates. Breast cancer incidence among Asian women living in the United States was 1.5-4 times higher than the corresponding incidence rate in the women's respective countries of origin.
Breast cancer incidence is expected to continue to increase for the next 10 years in Asia and may approach rates reported among Asian-Americans. The number and mean age of breast cancer cases is expected to increase as the female Asian population ages, the prevalence of certain risk factors changes (early menarche, late menopause, low parity, late age at first live birth, and low prevalence of breastfeeding), and as Asian countries introduce mass screening programs.
Full-text · Article · Nov 2010 · Cancer Causes and Control
[Show abstract][Hide abstract]ABSTRACT: Since 1980, sunbed use and travel abroad have dramatically increased in Iceland (64°-66°N). The authors assessed temporal trends in melanoma incidence by body site in Iceland in relation to sunbed use and travel abroad. Using joinpoint analysis, they calculated estimated annual percent changes (EAPCs) and identified the years during which statistically significant changes in EAPC occurred. Between 1954 and 2006, the largest increase in incidence in men was observed on the trunk (EAPC = 4.6%, 95% confidence interval: 3.2, 6.0). In women, the slow increase in trunk melanoma incidence before 1995 was followed by a significantly sharper increase in incidence, mainly among women aged less than 50 years, resembling an epidemic incidence curve (1995-2002: EAPC = 20.4%, 95% confidence interval: 9.3, 32.8). In 2002, the melanoma incidence on the trunk was higher than the incidence on the lower limbs for women. Sunbed use in Iceland expanded rapidly after 1985, mainly among young women, and in 2000, it was approximately 2 and 3 times the levels recorded in Sweden and in the United Kingdom, respectively. Travels abroad were more prevalent among older Icelanders. The high prevalence of sunbed use probably contributed to the sharp increase in the incidence of melanoma in Iceland.
Full-text · Article · Oct 2010 · American journal of epidemiology
[Show abstract][Hide abstract]ABSTRACT: To examine changes in temporal trends in breast cancer mortality in women living in 30 European countries.
Retrospective trend analysis. Data source WHO mortality database on causes of deaths Subjects reviewed Female deaths from breast cancer from 1989 to 2006
Changes in breast cancer mortality for all women and by age group (<50, 50-69, and >or=70 years) calculated from linear regressions of log transformed, age adjusted death rates. Joinpoint analysis was used to identify the year when trends in all age mortality began to change.
From 1989 to 2006, there was a median reduction in breast cancer mortality of 19%, ranging from a 45% reduction in Iceland to a 17% increase in Romania. Breast cancer mortality decreased by >or=20% in 15 countries, and the reduction tended to be greater in countries with higher mortality in 1987-9. England and Wales, Northern Ireland, and Scotland had the second, third, and fourth largest decreases of 35%, 29%, and 30%, respectively. In France, Finland, and Sweden, mortality decreased by 11%, 12%, and 16%, respectively. In central European countries mortality did not decline or even increased during the period. Downward mortality trends usually started between 1988 and 1996, and the persistent reduction from 1999 to 2006 indicates that these trends may continue. The median changes in the age groups were -37% (range -76% to -14%) in women aged <50, -21% (-40% to 14%) in 50-69 year olds, and -2% (-42% to 80%) in >or=70 year olds.
Changes in breast cancer mortality after 1988 varied widely between European countries, and the UK is among the countries with the largest reductions. Women aged <50 years showed the greatest reductions in mortality, also in countries where screening at that age is uncommon. The increasing mortality in some central European countries reflects avoidable mortality.
[Show abstract][Hide abstract]ABSTRACT: Breast cancer risk is increasing in most Asian female populations, but little is known about the long-term mortality trend of the disease among these populations. We extracted data for Hong Kong (1979–2005), Japan (1963–2006), Korea (1985–2006), and Singapore (1963–2006) from the World Health Organization (WHO) mortality database and for Taiwan (1964–2007) from the Taiwan cancer registry. The annual age-standardized, truncated (to ≥20 years) breast cancer death rates for 11 age groups were estimated and joinpoint regression was applied to detect significant changes in breast cancer mortality. We also compared age-specific mortality rates for three calendar periods (1975–1984, 1985–1994, and 1995–2006). After 1990, breast cancer mortality tended to decrease slightly in Hong Kong and Singapore except for women aged 70+. In Taiwan and Japan, in contrast, breast cancer death rates increased throughout the entire study period. Before the 1990s, breast cancer death rates were almost the same in Taiwan and Japan; thereafter, up to 1996, they rose more steeply in Taiwan and then they began rising more rapidly in Japan than in Taiwan after 1996. The most rapid increases in breast cancer mortality, and for all age groups, were in Korea. Breast cancer mortality trends are expected to maintain the secular trend for the next decade mainly as the prevalence of risk factors changes and population ages in Japan, Korea, and Taiwan. Early detection and treatment improvement will continue to reduce the mortality rates in Hong Kong and Singapore as observed in Western countries.
(Cancer Sci 2010; 101: 1141–1246)
[Show abstract][Hide abstract]ABSTRACT: Breast cancer in women is a major public health problem throughout the world. It is the most common cancer among women both
in developed and developing countries. One in ten of all new cancers diagnosed worldwide each year is a cancer of the female
breast. It is also the principal cause of death from cancer among women globally. More than 1.1 million cases are diagnosed
and more than 410,000 patients die of it worldwide (Ferlay et al. 2004). It is the second most common cancer now, after lung
cancer, when ranked by cancer occurrence in both sexes. About 55% of the global burden is currently experienced in developed
countries, but incidence rates are rapidly rising in developing countries. We review the global burden of breast cancer, focusing
on patterns of disease in terms of incidence and mortality and their geographical and temporal variations in different regions
of the world. We also discuss briefly the sources and methods of estimation, validity and completeness of available data,
and possible explanations for the observed patterns of incidence and mortality.
[Show abstract][Hide abstract]ABSTRACT: We assessed changes in advanced cancer incidence and cancer mortality in eight randomized trials of breast cancer screening.
Depending on published data, advanced cancer was defined as cancer > or = 20 mm in size (four trials), stage II+ (four trials), and > or = one positive lymph node (one trial). For each trial, we obtained the estimated relative risk (RR) and 95% CI between the intervention and control groups, for both breast cancer mortality and diagnosis of advanced breast cancer. Using a meta-regression approach, log(RR-mortality) was regressed on log(RR-advanced cancer), weighting each trial by the reciprocal of the square of the standard error of log(RR) for mortality.
RR for advanced breast cancer ranged from 0.69 (95% CI, 0.61 to 0.78) in the Swedish Two-County Trial to 0.97 (95% CI, 0.97 to 1.25) in the Canadian National Breast Screening Study-1 (NBSS-1) trial. Log(RR)s for advanced cancer were highly predictive of log(RR)s for mortality (R(2) = 0.95; P < .0001), and the linear regression curve had a slope of 1.00 (95% CI, 0.76 to 1.25) after fixing the intercept to zero. The slope changed only slightly after excluding the Two-County Trial and the Canadian NBSS-1 and NBSS-2 trials.
In trials on breast cancer screening, for each unit decrease in incidence of advanced breast cancer, there was an equal decrease in breast cancer mortality. Monitoring of incidence of advanced breast cancer may provide information on the current impact of screening on breast cancer mortality in the general population.
Full-text · Article · Nov 2009 · Journal of Clinical Oncology
[Show abstract][Hide abstract]ABSTRACT: Age-adjusted incidence rates of breast cancer vary greatly worldwide with highest rates found in the typically 'westernised' countries of North America and Europe. Much lower rates are observed in Asian and African populations but an exception to this has been reported for the Manila Cancer Registry in the Philippines. The reason for this high rate is unknown but may be associated with the change in lifestyle that has occurred in urban Manila since the 1960s. In 1995, a randomised controlled trial was set up in Manila to evaluate the feasibility of a screening intervention by clinical breast examination as an alternative to mammography. The cohort of 151,168 women was followed-up to 2001 for cancer incidence and a nested case-control study carried out. This aimed to evaluate the increase in breast cancer risk associated with known risk factors. Increased risks were seen for a high level of education (OR = 1.9 95%CI 1.1-3.3 for education stopped at > or =13 versus <13 years), nulliparity (OR = 5.0 95% CI 2.5-10.0 for nulliparity versus five or more children), and late age at first birth (OR = 3.3 95% CI 1.3-8.3 for age > or =30 versus <20 years). We found no association with excess body weight, height, use of exogenous hormones or alcohol consumption. From this study, the recognised "classical" risk factors do not fully explain the high breast cancer incidence in Metro Manila, especially when compared to other urban Asian populations. We conclude that it is too simplistic to ascribe the high risk to 'westernisation'.
Full-text · Article · Aug 2009 · International Journal of Cancer
[Show abstract][Hide abstract]ABSTRACT: Since 1985 considerable changes have taken place in the early detection and treatment of breast cancer. We quantified breast cancer trends for 35 countries with populations mainly of European ancestry.
Incidence data were extracted from cancer registries and mortality data from World Health Organization database. Overall percentage change from 1990 to 2002 was quantified for all ages and for three different age-groups (35-49, 50-69 and >/=70 years of age).
The incidence percent change in women of all ages varied from 2.1% in Canada to 54.2% in Lithuania. Main increases in incidence were observed for women 50-69 years old, from 12.4% in Canada until 105.3% in Norway. Decreases in mortality of >20% were observed in nine countries. Mortality decreases were highest in women 35-49 years old and lowest in women >/=70 years. The magnitude of mortality decrease from 1990 to 2002 was not related to the mortality rate observed in 1990.
While increases in breast cancer incidence mainly concerned women >/=50 years, decreases in mortality were more marked in women 35-49 years old. Large disparities in changes in mortality rates probably reflect differences in detection of and management of breast cancer.
Full-text · Article · Jul 2008 · Annals of Oncology
[Show abstract][Hide abstract]ABSTRACT: Mammography screening and menopause hormone therapy is essentially offered to women 50-69 years old.
In 28 European ancestry countries, we quantified changes in breast cancer incidence and mortality using a joinpoint regression analysis from 1960 until last year of available data.
Since 1960, increases in incidence often in the order of 2%-3% per year occurred in all countries, mainly in women 50-69 years old whose incidence in eight countries surpassed the incidence in women 70 years old and more. In 10 countries, a decrease in incidence in women >or=70 years was noticeable in the last years of observation, but the magnitude of this decrease was far from matching the magnitude of the increases observed in the 50-69 age-group. In the beginning of years 2000s, a persistent decrease in mortality of approximately 2% per year was observed in women 50-69 years old in most countries and parallel declines in mortality were observed in women 70 years or more.
In years 2000s, in a number of countries, the incidence of breast cancer has become greater in middle-aged women than in older women. If trends remain unchanged, the same phenomenon is likely to happen in other countries.
Full-text · Article · May 2008 · Annals of Oncology