Aspirin, commonly used for prevention of cardiovascular and cerebrovascular diseases, has been found to possess protective effects against cancer development in the Western populations. Such effects among Asian populations remain uncertain. The objective of this study is to investigate the use of aspirin on prevention of different cancers among Chinese users. This population‐based study utilized database from the Hong Kong Hospital Authority; adults with aspirin prescription for at least 6 months between 2000 and 2004 were included and followed up until 2013. Aspirin users were age‐sex matched with non‐aspirin users at a 1:2 ratio. Incidences of cancer were the primary outcome measured by relative risk (RR). A total of 204,170 aspirin users and 408,339 non‐aspirin users were included, with the mean age 67.5 years, 7.7 years average duration of aspirin prescription and 80 mg as the median dose of aspirin. Cancer incidences were found in 26,929 (13.2%) aspirin users and 70,755 (17.3%) non‐aspirin users. Compared with patients who had not been prescribed aspirin, aspirin usage led to significant reduction of cancers in liver (RR: 0.49), stomach (RR: 0.42), colorectum (RR: 0.71), lung (RR: 0.65), pancreas (RR: 0.54), oesophagus (RR: 0.59) and leukaemia (RR: 0.67). There was no demonstrable reduction of kidney cancer, bladder cancer, prostate cancer and multiple myeloma in association with the usage of aspirin. Risk of breast cancer was shown to marginally increase (RR: 1.14) with aspirin usage. This study demonstrated that the long‐term use of low‐dose aspirin is associated with the reduction in risk of various cancers but not for breast cancer. Further investigation is needed before promoting aspirin as a primary chemoprotective agent.

Background: Colorectal cancer incidence among young adults in the United States is on the rise, but whether this phenomenon is present in other parts of the world is not well documented. This study aims to explore the temporal change of incidence rates for colorectal cancer in various countries across the globe. Methods: We extracted colorectal cancer incidence and population data from 1988 to 2007 based on data from the International Agency for Research on Cancer and compared incidence between age groups. Twelve representative jurisdictions from five continents were selected. Young-onset colorectal cancer cases were defined as those ages <50 years. Joinpoint regression was used to measure the trends of colorectal cancer incidence and to estimate the annual percent change (APC). Results: The APC for those ages <50 years was noted to be increasing at a faster rate as compared with those ages !50 years in many regions, including Australia (þ1.10% vs. À0.35%), Brazil (þ9.20% vs. þ5.72%), Canada (þ2.60% vs. À0.91%), China-Hong Kong (þ1.82% vs. À0.10%), China-Shanghai (þ1.13% vs. À2.68%), Japan (þ2.63% vs. þ0.90%), the United Kingdom (þ3.33% vs. þ0.77%), and the United States (þ1.98% vs. À2.88%). These trends were largely driven by rectal cancer, except in Brazil and the United Kingdom. Conclusions: Increasing incidence of young-onset colorectal cancer was noted in many regions across the globe. Impact: Further studies focusing on young-onset colorectal cancer, particularly with regard to risk factors and establishing the optimal age of screening, are warranted.

To investigate the global incidence of prostate cancer with special attention to the changing age structures. Data regarding the cancer incidence and population statistics were retrieved from the International Agency for Research on Cancer in World Health Organization. Eight developing and developed jurisdictions in Asia and the Western countries were selected for global comparison. Time series were constructed based on the cancer incidence rates from 1988 to 2007. The incidence rate of the population aged ≥ 65 was adjusted by the increasing proportion of elderly population, and was defined as the “aging-adjusted incidence rate”. Cancer incidence and population were then projected to 2030. The aging-adjusted incidence rates of prostate cancer in Asia (Hong Kong, Japan and China) and the developing Western countries (Costa Rica and Croatia) had increased progressively with time. In the developed Western countries (the United States, the United Kingdom and Sweden), we observed initial increases in the aging-adjusted incidence rates of prostate cancer, which then gradually plateaued and even decreased with time. Projections showed that the aging-adjusted incidence rates of prostate cancer in Asia and the developing Western countries were expected to increase in much larger extents than the developed Western countries.

With the exception of the United States, the incidence of CRC is expected to continue to rise in most regions in the coming decades, due to population growth and changes in demographic structure. The predicted increases are more marked in developing regions with limited health care resources.

The incidence rates of lung, colorectal and prostate cancers will continue to rise in the future decades due to the rise of ageing population. Lifestyle modification such as cutting tobacco smoking rates and promoting healthier diets as well as cancer screening programs should be a health system priority in order to decrease the growing burden of cancer-related mortality and morbidity.