These were some of the conclusions of the study, “Gender-specific spatio-temporal patterns of colorectal cancer incidence in Navarre, Spain (1990-2005)“, carried out by researchers from the Public University of Navarre and the Institute of Public Health of Navarre, and published online in the Cancer Epidemiology journal.
In concrete, the work was undertaken by Ms Lola Ugarte, Ms Jaione Etxeberria and Mr Tomás Goicoa, researchers at the Department of Statistics and Operative Research at the UPNA, and by Ms Eva Ardanaz, from the Institute of Public Health of Navarre. Both for researchers and those responsible for policies in the territory, it is of great use to have studies of cancer rates detailed according to geographical areas, in order to carry out better evaluations and apply more specific prevention programmes and strategies.
This research — analysing cancer rates, not those of mortality — evaluated the spatio-time patterns of colorectal cancer amongst men and women in various parts of Navarre, using data from its cancer register between 1990 and 2005 agglutinating the number of health zones into thirteen: 4 large areas outside the capital city of Pamplona (Pyrenees north-zone, south Ebro river valley zone, the eastern zone and the western zone); and 9 areas within Pamplona city itself (San Jorge, Rochapea/Ansoain, Chantrea, the Old Town/I Ensanche, II Ensanche, Milagrosa/Azpilagaña/Mendillorri, Iturrama, San Juan and Ermitagaña).
According to the analysis, the rate of this cancer in Navarra “has tended to rise, for both sexes, over the past decades, although the death rates have remained stable”. With respect to colorectal cancer incidence, cancer of the colon represents 57.6% in men and 65.4% in women. The average age for diagnosis amongst men was 70.8 years (colon) and 69.8 years (rectum), the corresponding figures amongst women being 72.9 and 71.4 respectively. It should be pointed out that, for women, Navarra has lower rates than the other industrialised countries of Europe and North America.
Of the total of 5,912 cases of colorectal cancer registered in Navarre (58.8% were amongst men (3,053). Amongst men the risk of incidence of this cancer is growing in all zones and the risk is significantly greater in the II Ensanche, Milagrosa / Azpilagaña / Mendillorri and San Juan zones when compared to Navarre overall. In women, the risks showed a slight increase in all the zones over the period studied. The incidence risk in the South of Navarre is significantly less than that of the Community overall.
By age, a rise in cancer rates in men was recorded from the ages of 35-39 to 80-84, when the rate begins to drop. Amongst women, the initiation group was also the 35 to 39 age range.
Set up detection programmes
Survival rates in Spain tend to be slightly greater amongst women than men (54.4% compared to 53.4%), and improvements have been made especially amongst younger patients, “probably due to positive changes in the treatment of colorectal cancer”. Preliminary results from high-resolution studies of colorectal cancer in which Navarre, Tarragona and Granada participated “showed good clinical practices in chemotherapy with coadjuvant radiotherapy, Navarre being one of the regions where this form of treatment is most frequent”.
In this context, it is pointed out that, “given the impact of this type of cancer in Spain, particularly Navarre, the introduction of programmes for prevention and early detection could help change the cancer rate trend”. Some Autonomous Communities such as Catalonia, Valencia and Murcia, following recommendations of the European Union and the national health system, have implemented these types of programmes, aimed at the public between 50 and 69 years.
While in certain regions of the developed world the incidence of colorectal cancer has dropped (Australia, United Kingdom, France and Canada), in others a considerable increase has been noted, including Spain, where rates have increased since the 1970s, especially amongst men. “This difference between sexes — the research pointed out — may be due to variations in the ingestion of alcohol, the consumption of fruit and vegetables, physical activity, obesity, consumption of tobacco and a family history of colorectal cancer”. Amongst all, the consumption of fruit and vegetables is one of the aspects most firmly related to the protection factors for cancer. “Thus, it is necessary to continue promoting healthy life styles for the primary prevention amongst men and women of all ages”, the researchers pointed out.
Worldwide, colorectal cancer is the fourth most common cancer amongst men and the third most common amongst women. In Spain it is the second most frequent in women, after breast cancer. Amongst men it is considered the second or third, after lung and prostate cancer. From 5o years on, it becomes a risk factor, rising by a factor 1.5 to 2 times every ten years.