New data and analyses from a long-running study of cancer survival in Europe have shown that the number of people actually cured of cancer - rather than just surviving for at least five years after diagnosis - is rising steadily.
A special issue of the European Journal of Cancer containing reports from the EUROCARE-4 Working Group, includes, for the first time, an estimate of the proportions of patients who are cured of their cancer in Europe and who, therefore, have a life expectancy equal to that of the rest of the population. The analysis divides patients into two groups - the proportion who may be considered cured of their disease and who are likely to die of something else, and those who will die of their cancer.
The study compared two periods - 1988-1990 and 1997-1999 - and found the proportion of patients estimated to be cured of lung, stomach and colorectal cancers increased from 6% to 8%, from 15% to 18% and from 42% to 49%, respectively.
Dr Riccardo Capocaccia of the National Centre for Epidemiology, Surveillance and Health Promotion (Rome, Italy), who is the guest editor of the EUROCARE-4 special issue, said: "Increases between 1988-1990 and 1997-1999 in the estimated proportion of European patients cured of lung, stomach and colorectal cancers are noteworthy. The proportion cured is not affected by 'lead time' (earlier diagnosis without improvement in life expectancy), so these trends suggest genuine progress in cancer control."
However, as with many other papers in the EJC special issue, the paper on the proportion of cured patients showed there were significant differences between countries in Europe.
For all cancers combined, most men (47%) were cured in Iceland and most women (59%) were cured in France and Finland, while in Poland the least men (21%) and women (38%) were cured.
Dr Capocaccia said: "For all cancers combined, the very wide range in the proportion of patients cured in the contributing countries, ranging from 21% to 47% in men and 38% to 59% in women, also depends on the varying frequency across Europe of the different cancers. This proportion is, therefore, also an indicator of Europe-wide variations in cancer control, because it reflects progress in diagnosis and treatment, as well as success in the prevention of the most fatal cancers.
"Geographic variation in the estimated proportion of patients diagnosed in 1988-1999 who were cured ranged from about 4% to 10% for lung cancer, from 9% to 27% for stomach cancer, from 25% to 49% for colon and rectum cancer, and from 55% to 73% for breast cancer."
For instance, Denmark, Czech Republic and Poland had the lowest proportion of cured lung cancer patients (less than 5%), while France and Spain had the highest (more than 10%). For colorectal cancer, less than 30% were cured in Poland, Czech Republic and Slovenia but 49% were cured in France. In Finland, France, Spain and Sweden, about 73% of breast cancer patients were cured, while the proportion was less than 60% in Czech Republic, Poland and Slovenia.
For prostate cancer, the proportion of men cured was associated more with the intensity of PSA testing activity than with the efficacy of treatments. France led the way with more than 60% of men cured, while only 14% were cured in Denmark. This difference was largely due to cases diagnosed earlier through the PSA test, and many of these prostate cancers would not have killed and might not even have given rise to any symptoms. Indeed, prostate cancer mortality was no higher in Denmark than elsewhere in Northern Europe.
For breast cancer, results showed a gap between Poland, the Czech Republic and Slovenia and more western European countries of about 10%. "Part of this difference has been attributed to the introduction of breast cancer screening from the mid-1990s in several western European countries. If this is true, the implication is that early diagnosis saves the lives of women with breast cancer by rendering their disease more curable," said Dr Capocaccia.
The EUROCARE study has been running since 1990 and is the widest epidemiological study on the survival of cancer patients in Europe. This most recent report, EUROCARE-4, includes data from 93 population-based cancer registries in 23 European countries, covering a total population of about 151,400,000, which represents 35% of the total population in those countries. The EUROCARE-4 database contains the anonymised records for more than 13,500,000 cancer patients diagnosed during the period 1978-2002, with information on their vital status up to 31 December 2003 or later. Preliminary data on survival from EUROCARE-4 were published in 2007.
In addition to the estimates of the proportion of patients cured, data in the EJC special issue that are new since 2007 include comparisons of survival between the elderly and the middle-aged, between men and women and the survival of children.
Survival of the elderly (70-99 years) was lower than for middle-aged patients (55-69 years). Dr Capocaccia said: "This is probably due to more advanced stage of disease at diagnosis, other serious conditions, and more difficult access to, or lack of availability of, appropriate care. The difference was particularly evident for women. During the period 1995-2002 covered by EUROCARE-4, five-year survival improved less for patients aged 70-84 than for those aged 55-69, widening the gap in survival between these two age bands. Survival differences between the oldest and middle-aged patients were mainly concentrated in the first year after diagnosis: five-year survival conditional on survival for the first year after diagnosis varied much less with age than unconditional five-year survival, suggesting that older patients are often diagnosed too late to be efficiently treated."