Despite considerable progress in our understanding of the process of carcinogenesis, total cancer mortality rose steadily in North America and Europe up to the late 1980s. The 1998 Annual Report to the Nation on the Status of Cancer in the United States showed a persisting decline of cancer mortality in males and females.1 We therefore considered the available data on cancer mortality in the European Union (EU).
Peak age- and sex-standardized cancer mortality rates in the EU were registered in 1988, and overall cancer mortality declined by about 7% between 1988 and 1996.2 This trend was similar to the decline observed in the USA since 1991, approaching 8% between 1991 and 1997 for both sexes combined. In 1997, for the first time, the absolute number of cancer deaths also declined in the USA.1, 3, 4
We have now updated to 1997 the analyses of trends in cancer mortality for the EU, on the basis of official cancer death certifications and population estimates for the 15 countries of the EU obtained from the World Health Organization (WHO) database.2 From the matrices of certified deaths and resident populations, age-specific rates for each 5-year age group and calendar period were computed. Age-standardized and age- and sex-standardized rates (for both sexes combined) were based on the world standard population. Cancer proportional mortality, i.e., the standardized proportion of cancer death on all deaths, was also given.
Table I gives age- and sex-standardized mortality rates from all neoplasms, from lung, stomach, intestines (mainly colon and rectum), breast, prostate, leukemias and from all other neoplasms, together with the proportion of cancer deaths for the period 1988–1997. Total cancer mortality declined by 9.1%, from 147.0 in 1988 to 133.6/100,000 in 1997. Lung cancer mortality declined by 9.6%, from 31.1 to 28.1/100,000. Other neoplasms showing appreciable declines were stomach (from 10.5 to 7.4/100,000, −29.5%), intestines (from 17.0 to 14.4, −15.3%), uterus (cervix and corpus, from 6.3 to 4.9, −22.2%), female breast (from 22.4 to 20.2, −9.8%), prostate (after 1995) and leukemias (from 4.8 to 4.3, −10.4%); no appreciable change was observed for all other neoplasms combined. Given the greater decline in other causes of death, cancer proportional mortality, however, increased from 24.7 to 25.8%.
|Year||All cancers||Lung||Stomach||Intestines||Breast2||Uterus3||Prostate||Leukemias||All other neoplasms||CPM4 (%)|
|Change in rate, 1988–97||−13.4 (−9.1%)||−3.0 (−9.6%)||−3.1 (−29.5%)||−2.6 (−15.3%)||−2.2 (−9.8%)||−1.4 (−22.2%)||−0.4 (−2.6%)||−0.5 (−10.4%)||−0.2 (−0.5%)|
Table II gives sex-specific age-adjusted rates for all cancers, lung and colorectal cancer in males and females separately.The fall in total cancer mortality was greater in males (−18/100,000) than in females (−9/100,000), mainly due to a different trend in lung cancer (downward in males and upward in females). Intestinal cancer mortality, in contrast, declined more in females than in males. The downward trends for stomach cancer were from 14.5 to 10.1 (−30%) in males and from 6.7 to 5.0 (−19%), in females. Those from leukemias were from 6.0 to 5.3 (−12%) in males and from 3.7 to 3.3 (−11%) in females.
|Change in rate 1988–97||−17.5||−9.4||−6.9||+0.8||−2.5||−2.9|
The present update report further quantifies the existence of a steady decline in cancer mortality for both sexes combined in the EU. Such a decline was over 9% during the decade 1988–97 and hence corresponds to the avoidance of approximately 80,000 deaths (48,500 males and 31,500 females) in 1997 compared with the sex- and age-specific mortality rates registered in 1988. Of these, 24,000 were due to stomach cancer, 23,000 to lung and 22,000 to colorectum; 39,000 were in the population below age 65 years and 41,000 were above. As in the USA,4 for the first time in the EU, the total number of cancer deaths also declined in 1997, from 956,000 to 952,000.
In the USA, the major components of the decline in cancer mortality between 1991 and 1996 were colorectum (22%), breast (21%), lung (19%) and prostate (13%).5 The major difference in the EU is the persistent importance of the fall in gastric cancer, whose rates were, however, still considerably higher than in North America.6
The favorable trends within Europe are therefore partly due to the decline in lung (and other tobacco-related) neoplasms in males, caused by downward trends in smoking prevalence over the last few decades,7–9 and partly to the persisting fall in gastric cancer (and the more recent decline in intestinal cancer rates), which is possibly related to dietary improvements.10 Some of the decline is attributable to improved screening and early diagnosis for cervical and perhaps colorectal, breast and prostate cancer.11 Furthermore, advances have been made in treatment for leukemias12 and other neoplasms amenable to therapy. These include breast and prostate cancers, which are among the few common neoplasms for which appreciable advances in survival have been observed over the last few years, following the adoption of screening and consequent early diagnosis. In the EU, such increased survival is mainly attributed to improved treatment, including essentially widespread adoption of polychemotherapy and hormonal therapy regimens for breast cancer.13–16 Hormone treatment may also increase survival from prostate cancer in elderly men, who may consequently die from other causes.17, 18
The declines for breast cancer may approach 25% between 1950 and 2000 in the USA and the UK, which started from higher rates, but such declines are smaller for the whole EU, indicating the potential scope for further advances.13, 14 Likewise, the decline in prostate cancer mortality between 1991 and 1997 was 17% in the USA,19 with rates below the levels of 1986, whereas in the EU only a 3% decline was observed after 1995,20 again indicating the scope for further reductions in mortality from this common neoplasm, through early diagnosis and more rational integrated treatment approaches. Some improvement in rectal cancer survival through adjuvant radiotherapy has also been reported, but the impact on overall survival appears to be marginal.21
In conclusion, it is clear that the decline in cancer mortality observed over the last decade in the EU is largely due to advances in prevention of lung cancer, other tobacco-related neoplasms and also gastric cancer. Advances in cancer treatment have also played an appreciable role, not only for germ-cell and lymphoid neoplasms, but also for hormone-related cancers, including prostate and mainly breast cancer. Early diagnosis is the main determinant of the fall in cervical cancer mortality, but its role for other neoplasms, including colorectum, breast and prostate, remains inadequately explored and quantified on a European scale.