br Conclusions br Author contributions br Declarations
Declarations of interest
Acknowledgments The Radiation Effects Research Foundation (RERF), Hiroshima and Nagasaki, Japan is a public interest foundation funded by the Japanese Ministry of Health, Labour and Welfare (MHLW) and the US Department of Energy (DOE) through DOE award DE-HS0000031 to the National Academy of Sciences. This publication was supported by RERF Research Protocol RP S1-18. The views of the authors do not necessarily reflect those of the two governments. GM was funded by a Fulbright Global Scholar Award. The authors thank Mrs. Hiroko Moriwaki for the preparation of the dataset for analysis.
Introduction Cancer incidence and mortality have been increasing in China, making cancer the leading cause of death since 2010 and a major public health concern . Much of the increasing burden of cancer is attributable to population growth and socio-demographic changes . As the economic center of China, Shanghai has gained remarkable achievements in both economy and healthcare infrastructure in the last few decades. For example, the life expectancy in Shanghai has increased from 73.3 years in 1982 to 82.5 years in 2013 . One of the resultant socio-demographic changes in Shanghai is the dramatic increase in the number of older adults (age ≥ 65). Specifically, there has been a three-fold increase in the population size of older people in urban Shanghai over the last four decades, from 0.34 million in 1973 to 1.15 million in 2013 . The proportion of older people in urban Shanghai was recorded as high as 18.6% in 2013. Since cancer occurs more commonly in older adults [4,5], the ageing population of Shanghai is expected to markedly increase in a concomitant number of cancer diagnoses. Moreover, the shifting trend to Western diets, change in occupational pattern, increased high risk behaviors (e.g. excessive calorie intake and physical inactivity), and changes in established cancer risk factors (e.g. smoking, hepatitis virus infection, and ambient air pollution) could result in an alteration of the cancer profile in Shanghai [6,7]. The incidence rate can serve as a crude proxy for shifting patterns of disease within a population, as well as clues to the changing risk factors . This information is critical for the understanding and planning of the disease burden, and permits an Ac-DEVD-CHO of the Shanghai Health System to respond to future challenges. Previous studies have described the cancer incidence trends in Shanghai but these were of retrospective design and consequently lack insight into the future burden of cancer [, , , ]. To address this need, we used data on those diagnosed with 27 selected cancers in urban Shanghai between 1988 and 2013 to project both the future number of cancer patients and cancer incidence to 2025.
Discussion The increase in cancer cases has been generally attributed to the change in cancer-related risk factors, population size, and population age structure . In urban Shanghai, the population size decreased by 12.0% from 1988 to 2013 and we anticipated an additional 12.5% decrease by 2025. However, while the overall resident numbers in Shanghai has strikingly increased by 87.5% from 1988 through 2013, the number of professional physicians has decreased from 4.2 per 1000–2.4 per 1000 during this period . This decrease might suggest that further shrinkage of health resource in Shanghai is likely, thereby imposing severe challenges on diagnosis and treatment of diseases that include cancer. On the other hand, the Shanghai population is still ageing, especially in the urban districts. The expanding aged population could be viewed as a sign of improved medical facilities and healthcare in Shanghai over the past decades. More importantly, this could herald a heavy disease burden in the geriatric population in the near future. For example, certain cancers are expected to increase in terms of absolute case numbers although their incidences may reduce. To address the anticipated surge in cancer incidence specifically in older adults, significant investments in research and targeted measures are needed. On the one hand, there should be a greater emphasis on primary prevention and early detection, such as eradication of Helicobacter pylori, wider implementation of HBV and HPV vaccination, and effective screening for cervical and colorectal cancer, are warranted [, , ]. On the other hand, growing evidence from diverse types of cancers such as breast, prostate, and glioblastoma suggest that age at diagnosis is a critical factor for both cancer biology and response to treatment [, , ]. As a result, randomized clinical trials and non-randomized clinical studies are urgently needed to identify clinically beneficial and cost-effective treatments tailored to older patients .