Peter Baade

Cancer statistics in China, 2015

With increasing incidence and mortality, cancer is the leading cause of death in China and is a major public health problem. Because of Chinas massive population (1.37 billion), previous national incidence and mortality estimates have been limited to small samples of the population using data from the 1990s or based on a specific year. With high‐quality data from an additional number of population‐based registries now available through the National Central Cancer Registry of China, the authors analyzed data from 72 local, population‐based cancer registries (2009‐2011), representing 6.5% of the population, to estimate the number of new cases and cancer deaths for 2015. Data from 22 registries were used for trend analyses (2000‐2011). The results indicated that an estimated 4292,000 new cancer cases and 2814,000 cancer deaths would occur in China in 2015, with lung cancer being the most common incident cancer and the leading cause of cancer death. Stomach, esophageal, and liver cancers were also commonly diagnosed and were identified as leading causes of cancer death. Residents of rural areas had significantly higher age‐standardized (Segi population) incidence and mortality rates for all cancers combined than urban residents (213.6 per 100,000 vs 191.5 per 100,000 for incidence; 149.0 per 100,000 vs 109.5 per 100,000 for mortality, respectively). For all cancers combined, the incidence rates were stable during 2000 through 2011 for males (+0.2% per year; P = .1), whereas they increased significantly (+2.2% per year; P < .05) among females. In contrast, the mortality rates since 2006 have decreased significantly for both males (−1.4% per year; P < .05) and females (−1.1% per year; P < .05). Many of the estimated cancer cases and deaths can be prevented through reducing the prevalence of risk factors, while increasing the effectiveness of clinical care delivery, particularly for those living in rural areas and in disadvantaged populations. CA Cancer J Clin 2016;66:115–132.

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.

Cancer survival in China, 2003-2005: A population-based study

Limited population‐based cancer registry data available in China until now has hampered efforts to inform cancer control policy. Following extensive efforts to improve the systematic cancer surveillance in this country, we report on the largest pooled analysis of cancer survival data in China to date. Of 21 population‐based cancer registries, data from 17 registries (n = 138,852 cancer records) were included in the final analysis. Cases were diagnosed in 2003–2005 and followed until the end of 2010. Age‐standardized relative survival was calculated using region‐specific life tables for all cancers combined and 26 individual cancers. Estimates were further stratified by sex and geographical area. The age‐standardized 5‐year relative survival for all cancers was 30.9% (95% confidence intervals: 30.6%‐31.2%). Female breast cancer had high survival (73.0%) followed by cancers of the colorectum (47.2%), stomach (27.4%), esophagus (20.9%), with lung and liver cancer having poor survival (16.1% and 10.1%), respectively. Survival for women was generally higher than for men. Survival for rural patients was about half that of their urban counterparts for all cancers combined (21.8% vs. 39.5%); the pattern was similar for individual major cancers except esophageal cancer. The poor population survival rates in China emphasize the urgent need for government policy changes and investment to improve health services. While the causes for the striking urban‐rural disparities observed are not fully understood, increasing access of health service in rural areas and providing basic health‐care to the disadvantaged populations will be essential for reducing this disparity in the future.

Cancer survival is dependent on season of diagnosis and sunlight exposure.

Sunlight is essential for the production of vitamin D in the body. Evidence exists to suggest that vitamin D metabolites may have a role in tumor growth suppression. In this large study, involving over a million cancer patients from the United Kingdom, we have analyzed the role of season of diagnosis and sunlight exposure in cancer survival for cancers of the breast, colorectum, lung, prostate and at all sites combined. We used population‐based data from the Thames Cancer Registry to analyze cancer survival in periods 0–1 and 0–5 years after diagnosis. The analysis was performed using Cox proportional regression analysis adjusting for age and period at diagnosis and including season of diagnosis and sunlight exposure in the preceding months as factors in the analysis. We found evidence of substantial seasonality in cancer survival, with diagnosis in summer and autumn associated with improved survival compared with that in winter, especially in female breast cancer patients and both male and female lung cancer patients (hazard ratios 0.86 [95% CI 0.83–0.89], 0.95 [95% CI 0.92–0.97] and 0.95 [95% CI 0.93–0.98] respectively). Cumulative sunlight exposure in the months preceding diagnosis was also a predictor of subsequent survival, although season of diagnosis was a stronger predictor than cumulative sunlight exposure. We found seasonality in cancer survival to be stronger in women than in men. Our results add to a growing body of evidence that vitamin D metabolites play an important role in cancer survival.

Presentation and detection of invasive melanoma in a high-risk population

BACKGROUND Early detection of melanoma has been encouraged in Queensland for many years, yet little is known about the patterns of detection and the way in which they relate to tumor thickness. OBJECTIVE Our purpose was to describe current patterns of melanoma detection in Queensland. METHODS This was a population-based study, comprising 3772 Queensland residents diagnosed with a histologically confirmed melanoma between 2000 and 2003. RESULTS Almost half (44.0%) of the melanomas were detected by the patients themselves, with physicians detecting one fourth (25.3%) and partners one fifth (18.6%). Melanomas detected by doctors were more likely to be thin (<0.75 mm) than those detected by the patient or other layperson. Melanomas detected during a deliberate skin examination were thinner than those detected incidentally. LIMITATIONS Although a participation rate of 78% was achieved, as in any survey, nonresponse bias cannot be completely excluded, and the ability of the results to be generalized to other geographical areas is unknown. CONCLUSION There are clear differences in the depth distribution of melanoma in terms of method of detection and who detects the lesions that are consistent with, but do not automatically lead to, the conclusion that promoting active methods of detection may be beneficial.

Diabetes mellitus and serum carotenoids: findings of a population-based study in Queensland, Australia

BACKGROUND Epidemiologic evidence suggests that serum carotenoids are potent antioxidants and may play a protective role in the development of chronic diseases including cancers, cardiovascular disease, and inflammatory diseases. The role of these antioxidants in the pathogenesis of diabetes mellitus remains unclear. OBJECTIVE This study examined data from a cross-sectional survey to investigate the association between serum carotenoids and type 2 diabetes. DESIGN Study participants were adults aged > or = 25 y (n = 1597) from 6 randomly selected cities and towns in Queensland, Australia. Study examinations conducted between October and December 2000 included fasting plasma glucose, an oral-glucose-tolerance test, and measurement of the serum concentrations of 5 carotenoid compounds. RESULTS Mean 2-h postload plasma glucose and fasting insulin concentrations decreased significantly with increasing quintiles of the 5 serum carotenoids--alpha-carotene, beta-carotene, beta-cryptoxanthin, lutein/zeaxanthin, and lycopene. Geometric mean concentrations for all serum carotenoids decreased (all decreases were significant except that of lycopene) with declining glucose tolerance status. Beta-carotene had the greatest decrease, to geometric means of 0.59, 0.50, and 0.42 micromol/L in persons with normal glucose tolerance, impaired glucose metabolism, and type 2 diabetes, respectively (P < 0.01 for linear trend), after control for potential confounders. CONCLUSIONS Serum carotenoids are inversely associated with type 2 diabetes and impaired glucose metabolism. Randomized trials of diets high in carotenoid-rich vegetables and fruit are needed to confirm these results and those from other observational studies. Such evidence would have very important implications for the prevention of diabetes.

International trends in prostate-cancer mortality: the decrease is continuing and spreading.

AbstractObjective: To measure recent changes in prostate-cancer mortality across 24 developed countries. Methods: Mortality data for men aged 50–79 years were obtained from the World Health Organisation mortality database and we assessed trends in age-standardised mortality rates using joinpoint regression models. Results: Significant reductions in prostate-cancer mortality were observed in United Kingdom, United States, Austria, Canada, Italy, France, Germany, Australia and Spain, and downward trends were also observable in the Netherlands, Ireland and Sweden. Conclusions: Mortality declines for prostate cancer are now evident in 12 out of the 24 developed countries considered in this analysis. Increases in PSA screening and better treatment of early-stage disease, possibly acting in combination, remain plausible hypotheses.

A systematic review of the impact of stigma and nihilism on lung cancer outcomes

BackgroundThis study systematically reviewed the evidence on the influence of stigma and nihilism on lung cancer patterns of care; patients’ psychosocial and quality of life (QOL) outcomes; and how this may link to public health programs.MethodsMedline, EMBASE, ProQuest, CINAHL, PsycINFO databases were searched. Inclusion criteria were: included lung cancer patients and/or partners or caregivers and/or health professionals (either at least 80% of participants had lung cancer or were partners or caregivers of lung cancer patients, or there was a lung cancer specific sub-group focus or analysis), assessed stigma or nihilism with respect to lung cancer and published in English between 1st January 1999 and 31st January 2011. Trial quality and levels of evidence were assessed.ResultsEighteen articles describing 15 studies met inclusion criteria. The seven qualitative studies were high quality with regard to data collection, analysis and reporting; however most lacked a clear theoretical framework; did not address interviewer bias; or provide a rationale for sample size. The eight quantitative studies were generally of low quality with highly selected samples, non-comparable groups and low participation rates and employed divergent theoretical and measurement approaches. Stigma about lung cancer was reported by patients and health professionals and was related to poorer QOL and higher psychological distress in patients. Clear empirical explorations of nihilism were not evident. There is qualitative evidence that from the patients’ perspectives public health programs contribute to stigma about lung cancer and this was supported by published commentary.ConclusionsHealth-related stigma presents as a part of the lung cancer experience however there are clear limitations in the research to date. Future longitudinal and multi-level research is needed and this should be more clearly linked to relevant theory.

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.