Since 1952, the Cancer Registry of Norway has promoted science, spread knowledge and helped reduce the cancer burden.
Based on statutory notification of cancer, the Cancer Registry of Norway first opened its doors in 1952 with a staff of three. This marked the start of a remarkable series of decades and an unbroken collaboration with the health services, NGOs and central authorities. The Registry's main focus was on the establishment and quality assurance of a database of incident cancer cases, in addition to production of statistics, overviews and reports (1).
In the post-war years, Norwegian public health was characterised by the decline in tuberculosis and the emergence of cancer and cardiovascular diseases (2). After an initiative by the newly established World Health Organization, tightly followed up by clear-sighted Norwegian community medicine experts, the old idea of producing a better overview of and insight into cancer epidemiology was realised.
Today's advanced epidemiological methods and biostatistics are a young science. One of their first victories concerned the association between smoking and lung cancer. As early as 1950, solid international studies presented what we would now refer to as irrefutable evidence of a causal relationship. Nevertheless, it would be two decades before Norway introduced a ban on advertising and raised the age limit for buying tobacco products from 15 to 16 years (3). Only in 1996 was the age limit raised to 18 years.
Gastric cancer, the most common form of cancer around 1910 (4), was already on the decline in the 1950s, according to statistics from the Cause of Death Registry. Today we can see the subsequent history in the annual statistical reports from the Cancer Registry of Norway (5, Fig. 5.3). We can also retrieve data from a freely accessible, interactive statistics generator on our website (6).
The desire to have breast cancer diagnosed at an earlier stage featured strongly in the public consciousness in the 1950s. The Norwegian Cancer Society organised a trial project with doctors manually examining women's breasts in four counties. The results were summarised by the head of the Cancer Registry of Norway in 1962, of course (we can say today) without any definite conclusions (7). What is interesting is the shared understanding by laypeople and professionals that the prospects improve when cancer is treated at an early stage.
The management of cancer has been marked by a dizzying development of diagnostic methods and therapies
Since 1980, the increasing research activity in the Cancer Registry of Norway has focused on studies of cancer patients and diagnostics, aetiological epidemiology and early diagnostics. In the 1990s, the Cancer Registry of Norway was charged with the organisation of mass screening programmes. In the same period, work started on what was to become a series of national medical quality registries for selected forms of cancer. The research investigated causal factors and biological markers in breadth and depth, and the quality of the registry data has become highly satisfactory (8). You can read more about the registry's diverse history and current activities in a special issue of the Norwegian Journal of Epidemiology published on the occasion of the anniversary (9).
The management of cancer has been marked by a dizzying development of diagnostic methods and therapies. Good diagnostic methods and thorough examinations also lead to more cancer diagnoses. This is one of the reasons for the increase we see in the age-standardised incidence rates for most cancers (5, Fig. 5.3). In addition, the rates may have been affected by changes to classifications, participation in mass screenings and variations in exposure to carcinogens over the lifespan. The total result will vary depending on the form of cancer we are looking at. Key exceptions from the general increase in cancer diagnoses can be seen for cervical cancer, and for gastric cancer in particular, where the decline has been consistent in both rates and absolute numbers.
In 1952, causes and risk factors were largely unknown. With our current knowledge, we can safely estimate that approximately 6 000 annual cases of skin cancer and lung cancer, i.e. 17–20 % of all incident cancer diagnoses in Norway, could have been avoided in the absence of smoking and careless suntanning habits. Not only the climate faces challenges associated with human behaviour, structural factors and economic interests.
The Norwegian lung cancer rates remain high, making it difficult to accept that nicotine producers continue to pressure the authorities to make their new products freely available. Do we want to make provisions for a future repetition of the old story of men who changed from snus, chewing tobacco and pipe smoking to widespread cigarette smoking? Over the last ten years, the rate of lung cancer among men has finally started to decline (5, Fig. 5.3). Among the youngest (16–24 years), the proportion of smokers is approaching zero, and anti-smoking campaigns among adults have forestalled a peak in the wave of lung cancer that threatened. However, an increasing population, longer life expectancy and persistent smoking among a considerable proportion of the older population are today causing a higher number of lung cancer cases than we have ever seen.
Fortunately, the mortality rate from many forms of cancer is declining (5, Fig. 9.1), including cancer types whose incidence rates are increasing. Mortality and survival should be interpreted in light of incidence rates. The trend may nevertheless be hard to explain when the age distribution, the time of diagnosis, the prevalence of risk factors and background morbidity all change simultaneously (10). The considerable progress made in cancer therapy is clearly also a factor behind the observed improvement in five-year relative survival for all cancers as a totality, from 30–40 % around 1965 to over 75 % in 2021 (5, p. 104).
Today, more people are affected by cancer, but the diagnosis is not necessarily as frightening as it once was. That is the result of a joint effort by the health services, research, the population, international collaboration, and last, but not least, the Cancer Registry of Norway.