Identificador: TDX:612
Autores: Pazos Escudero, Montserrat
Resumen:
Introduction: It was estimated, for year 2000, that more than ten million people would be diagnosed of colorectal cancers in the world and more than six million people would die of it. In Europe, the incidence of colorectal cancer has been growing since 1960 and the survival has also improved. In its etiology, next to a genetic base, is the westernized way of life the most important factor (mainly a diet rich in proteins and fats and poor in fruits and vegetables). The adenoma is the precancerous lesion. There's controversy about the best population screening strategy for this cancer. The standard treatment is surgery. Since 1990, is the benefit of adjuvant therapies (chemotherapy and radiotherapie) confirmed. Also, the polichemotherapie has shown a survival benefit for the patients with advanced disease. Objetives:To know the incidence and survival, at a population level, of colorectal cancer in Tarragona according to gender, age, subsite of origin, histology and stage. To study the temporal trends of these sanitary indicators: incidence and survival.To compare our results with the results of other population-based cancer registries of the world.To describe an epidemiological pattern for colorectal cancer in Tarragona.Methods:Descriptive epidemiological study of colorectal cancer in Tarragona between 1980 and 1998. The data come from the population-based Cancer Registry of Tarragona. Incidence rates: normal, rates and standard rates, adjusted to the world population (Segi, 1950) have been calculated, according to gender, age, subsite of origin, histology and stage. For the temporal trends study (1980-1998) we used the Poisson model and the joinpoint model and calculated the anual percentage of change for each category. The data have been compared with the data of other registries published in Cancer Incidence Five Continents.Survival rates: observed survival rate (Kaplan and Meier model) and relative survival rate (Ederer model) have been calculated, according to gender, age, subsite of origin, histology and stage. The Cox model was uded to study the association between the different variables and the time of survival for the years 1996 and 1997. A study of the evolution of survival rates was also made (1985-1998). The data have been compared with the data of other registries published in EUROCARE-3 and the data of the SEER Programm in USA..Resultados:The normal incidence rate is 56,5 cases/100.000 inhabitants*year for both genders together. The adjusted incidence rate is 61,7 for men and 51,3 for women. The most frequent subsite of origin is left colon cancer. After this comes rectal cancer and right colon cancer. The distribution according to stages (Dukes classification) is: A (13%), B (27%), C (27%), D (22%). The incidence rates have grown 3,3% each year in men and 2,5% in women. The trend is constant between 1980 and 1998. The subsite of origin with a fastest growth is right colon cancer (6,5% in men and 5,2% in women). The 5-years observed survival rate is 40,4% and the 5-year relative survival rate is 49%. According to age-groups, the 5-year relative survival rates are: 60% for people between 35-55 years old; 53% for the ones between 55-75 years old and 45% for the people older than 74 years old. According to stages, the 5-year relative survival rates are: A (90%), B (68%), C (47%) and D (3%). The stage is the most important prognostic factor, next to the age. Between 1985 and 1994 the 5-year relative survival rate has improved from 42% to 49%.Conclusions:Colorectal cancer is the most frequent cancer in Tarragona for both genders together and the incidence rates are in the average in comparison to other European countries. The incidence has grown fast and constant. The cause of this change is probably the most westernized way of life with the time (for example: the changes in the diet). The survival rates are also in the average of the European countries and have grow from 1985 till 1994, like in the other countries, probably because of improvements in the therapies.
Repositori URV