Danny R. Youlden

The International Epidemiology of Lung Cancer Geographical Distribution and Secular Trends

This review presents the latest available international data for lung cancer incidence, mortality and survival, emphasizing the established causal relationship between smoking and lung cancer. In 2002, it was estimated that 1.35 million people throughout the world were diagnosed with lung cancer, and 1.18 million died of lung cancer—more than for any other type of cancer. There are some key differences in the epidemiology of lung cancer between more developed and less developed countries. In more developed countries, incidence and mortality rates are generally declining among males and are starting to plateau for females, reflecting previous trends in smoking prevalence. In contrast, there are some populations in less developed countries where increasing lung cancer rates are predicted to continue, due to endemic use of tobacco. A higher proportion of lung cancer cases are attributable to nonsmoking causes within less developed countries, particularly among women. Worldwide, the majority of lung cancer patients are diagnosed after the disease has progressed to a more advanced stage. Despite advances in chemotherapy, prognosis for lung cancer patients remains poor, with 5-year relative survival less than 14% among males and less than 18% among females in most countries. Given the increasing incidence of lung cancer in less developed countries and the current lack of effective treatment for advanced lung cancers, these results highlight the need for ongoing global tobacco reform to reduce the international burden of lung cancer.

International epidemiology of prostate cancer: Geographical distribution and secular trends

This review outlines current international patterns in prostate cancer incidence and mortality rates and survival, including recent trends and a discussion of the possible impact of prostate-specific antigen (PSA) testing on the observed data. Internationally, prostate cancer is the second most common cancer diagnosed among men (behind lung cancer), and is the sixth most common cause of cancer death among men. Prostate cancer is particularly prevalent in developed countries such as the United States and the Scandinavian countries, with about a six-fold difference between high-incidence and low-incidence countries. Interpretation of trends in incidence and survival are complicated by the increasing impact of PSA testing, particularly in more developed countries. As Western influences become more pronounced in less developed countries, prostate cancer incidence rates in those countries are tending to increase, even though the prevalence of PSA testing is relatively low. Larger proportions of younger men are being diagnosed with prostate cancer and living longer following diagnosis of prostate cancer, which has many implications for health systems. Decreasing mortality rates are becoming widespread among more developed countries, although it is not clear whether this is due to earlier diagnosis (PSA testing), improved treatment, or some combination of these or other factors.

Trends in incidence of childhood cancer in Australia, 1983–2006

Background:There are few population-based childhood cancer registries in the world containing stage and treatment data.Methods:Data from the population-based Australian Paediatric Cancer Registry were used to calculate incidence rates during the most recent 10-year period (1997–2006) and trends in incidence between 1983 and 2006 for the 12 major diagnostic groups of the International Classification of Childhood Cancer.Results:In the period 1997–2006, there were 6184 childhood cancer (at 0–14 years) cases in Australia (157 cases per million children). The commonest cancers were leukaemia (34%), that of the central nervous system (23%) and lymphomas (10%), with incidence the highest at 0–4 years (223 cases per million). Trend analyses showed that incidence among boys for all cancers combined increased by 1.6% per year from 1983 to 1994 but have remained stable since. Incidence rates for girls consistently increased by 0.9% per year. Since 1983, there have been significant increases among boys and girls for leukaemia, and hepatic and germ-cell tumours, whereas for boys, incidence of neuroblastomas and malignant epithelial tumours has recently decreased. For all cancers and for both sexes combined, there was a consistent increase (+0.7% per year, 1983–2006) at age 0–4 years, a slight non-significant increase at 5–9 years, and at 10–14 years, an initial increase (2.7% per year, 1983–1996) followed by a slight non-significant decrease.Conclusion:Although there is some evidence of a recent plateau in cancer incidence rates in Australia for boys and older children, interpretation is difficult without a better understanding of what underlies the changes reported.

Epidemiology of prostate cancer in the Asia-Pacific region

The purpose of this paper was to examine and compare available data on incidence, mortality and survival for countries in the Asia-Pacific region. Incidence data were obtained from GLOBOCAN 2008, other online data sources and individual cancer registries. Country-specific mortality statistics by individual year were sourced from the World Health Organization Statistical Information System Mortality Database. All incidence and mortality rates were directly age-standardised to the Segi World Standard population and joinpoint models were used to assess trends. Data on survival were obtained from country-specific published reports where available. Approximately 14% (122,000) of all prostate cancers diagnosed worldwide in 2008 were within the Asia-Pacific region (10 per 100,000 population), with three out of every four of these prostate cancer cases diagnosed in either Japan (32%), China (28%) or Australia (15%). There were also about 42,000 deaths due to prostate cancer in the Asia-Pacific region (3 per 100,000). For the nine countries with incidence trend data available, eight showed recent significant increases in prostate cancer incidence. In contrast, recent decreases in prostate cancer mortality have been reported for Australia, Japan and New Zealand, but mortality has increased in several other countries. The lack of population-based data across most of the countries in this region limits the ability of researchers to understand and report on the patterns and distribution of this important cancer. Governments and health planners typically require quantitative evidence as a motivation for change. Unless there is a widespread commitment to improve the collection and reporting of data on prostate cancer it is likely that the burden of prostate cancer will continue to increase. Enhancing knowledge transfer between countries where there are differentials in capacity, policy and experience may provide the necessary impetus and opportunity to overcome at least some of the existing barriers.

Incidence and mortality of female breast cancer in the Asia- Pacific region

Objective To provide an overview of the incidence and mortality of female breast cancer for countries in the Asia-Pacific region. Methods Statistical information about breast cancer was obtained from publicly available cancer registry and mortality databases (such as GLOBOCAN), and supplemented with data requested from individual cancer registries. Rates were directly age-standardised to the Segi World Standard population and trends were analysed using joinpoint models. Results Breast cancer was the most common type of cancer among females in the region, accounting for 18% of all cases in 2012, and was the fourth most common cause of cancer-related deaths (9%). Although incidence rates remain much higher in New Zealand and Australia, rapid rises in recent years were observed in several Asian countries. Large increases in breast cancer mortality rates also occurred in many areas, particularly Malaysia and Thailand, in contrast to stabilising trends in Hong Kong and Singapore, while decreases have been recorded in Australia and New Zealand. Mortality trends tended to be more favourable for women aged under 50 compared to those who were 50 years or older. Conclusion It is anticipated that incidence rates of breast cancer in developing countries throughout the Asia-Pacific region will continue to increase. Early detection and access to optimal treatment are the keys to reducing breast cancer-related mortality, but cultural and economic obstacles persist. Consequently, the challenge is to customise breast cancer control initiatives to the particular needs of each country to ensure the best possible outcomes.

Health Status of Long-term Cancer Survivors: Results from an Australian Population-Based Sample

Background: Despite considerable knowledge about the effect of cancer during the early stages of treatment and survivorship, understanding the longer-term effect of cancer has only recently become a priority. This study investigated the health implications of longer-term cancer survivorship in an Australian, population-based sample. Methods: Using the Australian National Health Survey, 968 longer-term cancer survivors were identified, along with 5,808 age- and sex-matched respondents without a history of cancer. Four measures of health effect were compared (quality of life, health status, days out of role, and mental well-being), using polytomous and logistic regression analyses controlling for other selected chronic conditions. These models were applied across both groups overall, across groups stratified by presence/absence of cancer, and other chronic conditions, as well as by tumor site. Results: Compared with matched respondents without cancer, longer-term cancer survivors reported significant decrements in health status, days out of role, and mental well-being (all P < 0.02), but not in quality of life. The likelihood of poor health outcomes (including quality of life) was much higher among survivors who also reported comorbid chronic conditions. Despite mixed results across tumor site, melanoma and prostate cancer survivors fared better across most outcomes. Conclusions: Clear evidence of excess morbidity among Australian longer-term cancer survivors seems to be further exacerbated by the presence of comorbid chronic conditions. Consistent with recent U.S. studies, these results further support the importance of ongoing surveillance of the growing number of cancer survivors worldwide along with increased attention to interventions to improve long-term health outcomes. (Cancer Epidemiol Biomarkers Prev 2006;15(10):1969–76)

Time trends and latitudinal differences in melanoma thickness distribution in Australia, 1990–2006

This study investigated time trends and latitude differentials in the thickness distributions of invasive melanomas diagnosed in Australia between 1990 and 2006 using data from population‐based cancer registries. Trends in incidence rates were calculated by sex, age group, thickness, year at diagnosis and latitude. For thin (<1.00mm) melanomas the increase was very pronounced during the early 1990s (1990–1996, annual percentage change and 95% confidence interval: males +5.6(+3.5,+7.7); females +4.1(+1.7,+6.5), but then incidence rates became stable among both males (+0.6(−0.1,+1.4)) and females (−0.0(−0.9,+0.9)) of all ages between 1996 and 2006. In contrast, incidence of thick (>4.00 mm) melanomas continued to increase over the entire period (males +2.6(+1.9,+3.4); females +1.6(+0.6,+2.6)). Recent reductions in the incidence of thin melanomas were observed among young (<50 years) males and females, contrasted by an increase in thin melanomas among older people, and increases in thick melanomas among most age groups for males and elderly (75+) females. A strong latitude gradient in incidence rates was observed, with rates being highest in northern, more tropical areas and lowest in the most southern regions. However, the magnitude of the increase in thick melanomas was most pronounced in southern parts of Australia. The observed trends in thin melanomas can most likely be attributed to the impact of early detection and skin awareness campaigns. However, these efforts have not impacted on the continued increase in the incidence of thick melanomas, although some increase may be due to earlier detection of metastasising melanomas. This highlights the need for continued vigilance in early detection processes.

The International Epidemiology of Lung Cancer: Latest Trends, Disparities, and Tumor Characteristics

Introduction: Our aim was to update global lung cancer epidemiology and describe changing trends and disparities. Methods: We presented country‐specific incidence and mortality from GLOBOCAN 2012 by region and socioeconomic factors via the Human Development Index (HDI). Between‐ and within‐country incidence by histological type was analyzed by using International Agency for Research on Cancer data on cancer incidence on five continents. Trend analyses including data from the International Agency for Research on Cancer, cancer registries, and the WHO mortality database were conducted using joinpoint regression. Survival was compared between and within countries and by histological type. Results: In 2012, there were 1.82 and 1.59 million new lung cancer cases and deaths worldwide, respectively. Incidence was highest in countries with a very high HDI and lowest in countries with a low HDI (42.2 versus 7.9 in 100,000 for males and 21.8 versus 3.1 in 100,000 for females, respectively). In most countries with a very high HDI, as incidence in males decreased gradually (ranging from –0.3% in Spain to –2.5% in the United States each year), incidence in females continued to increase (with the increase ranging from 1.4% each year in Australia to 6.1% in recent years in Spain). Although histological type varied between countries, adenocarcinoma was more common than squamous cell carcinoma, particularly among females (e.g., in Chinese females, the adenocarcinoma‐to–squamous cell carcinoma ratio was 6.6). Five‐year relative survival varied from 2% (Libya) to 30% (Japan), with substantial within‐country differences. Conclusions: Lung cancer will continue to be a major health problem well through the first half of this century. Preventive strategies, particularly tobacco control, tailored to populations at highest risk are key to reducing the global burden of lung cancer.

The validity of the distress thermometer in prostate cancer populations

The Distress Thermometer (DT) is widely recommended for screening for distress after cancer. However, the validity of the DT in men with prostate cancer and over differing time points from diagnosis has not been well examined.

The relative risk of second primary cancers in Queensland, Australia: a retrospective cohort study

BackgroundCancer survivors face an increased likelihood of being subsequently diagnosed with another cancer. The aim of this study was to quantify the relative risk of survivors developing a second primary cancer in Queensland, Australia.MethodsStandardised incidence rates stratified by type of first primary cancer, type of second primary cancer, sex, age at first diagnosis, period of first diagnosis and follow-up interval were calculated for residents of Queensland, Australia, who were diagnosed with a first primary invasive cancer between 1982 and 2001 and survived for a minimum of 2 months.ResultsA total of 23,580 second invasive primary cancers were observed over 1,370,247 years of follow-up among 204,962 cancer patients. Both males (SIR = 1.22; 95% CI = 1.20-1.24) and females (SIR = 1.36; 95% CI = 1.33-1.39) within the study cohort were found to have a significant excess risk of developing a second cancer relative to the incidence of cancer in the general population. The observed number of second primary cancers was also higher than expected within each age group, across all time periods and during each follow-up interval.ConclusionsThe excess risk of developing a second malignancy among cancer survivors can likely be attributed to factors including similar aetiologies, genetics and the effects of treatment, underlining the need for ongoing monitoring of cancer patients to detect subsequent tumours at an early stage. Education campaigns developed specifically for survivors may be required to lessen the prevalence of known cancer risk factors.