Survival analysis in young and elderly patients with gastric cancer

Abstract

Gastric cancer is one of the most prevalent neoplasms in the world and in Brazil. According to Inca`s estimates, in our country, it was the fourth most prevalent one in men and the fifth in women. In the world, it is the fourth most frequent neoplasm, being extremely important, especially in Japan, where there is the biggest incidence in the planet. Except for Japan, stomach cancer is more common in developing countries, such as the ones in Africa and South America, than in developed countries. The neoplasm affects more people between their fifties and seventies, and, at these age, is more common in men than in women. This neoplasm has a high mortality rate. Even though it is the fourth cause of neoplasm in the world, when it comes to causes of death by neoplasm, it rises to the second place. The five-year survival rate after the diagnosis of gastric cancer is extremely low, for both men and women. Fortunately, it`s incidence is falling through the years, and this fact is associated with the use of refrigerators for the food conservation, allowing a feeding with more fresh vegetables and less need of salt to conserve food. However, in young adults (25-39 years), this tendency of fall in the incidence doesn`t apply. Since the 1980`s, these age group is behaving in an antagonist way and a rise in the frequency of gastric cancer is these population is being observed, which may be related with H. pylori and Epstein-Barr virus infection or with biggest ingestion of sodium by the youngies or even with the prolonged use of the proton`s bomb inhibitors. At this age group, the cancer has a different behavior from the classic description. It is more frequent in women and is mainly of the diffuse histological type, besides being more associated with the H. pylori infection. Some studies indicated that the disease is more aggressive when it affects the young, but that is not consensus. Just a few studies evaluated the prognosis of gastric cancer in young adults with less than 40 years old. In addition, in these studies, was not found consensus about the cancer prognosis at this age group. Since last century until this year, the studies disagree: some do not find a relevant difference between the eldest and the young patients' survival; others find that the survival is bigger in the young patients, despite a likely more aggressive disease. Just a few studies found a worse survival rate in the young patients. Even a large North-American recent study, with more strong results, it was not evaluated the survival rate according to the clinical staging or the histological kind of neoplasm. Besides, most of the studies were made in Japan, a country where, due to the high incidence of gastric cancer, there is a screening for the neoplasm, reducing its mortality rate and distancing results from the Brazilian reality. Therefore, because of the possibility of a different behavior and prognosis of the disease in young and in elderly patients, our study has the aim of compare the survival rate in all the patients diagnosed with gastric cancer in Sao Paulo state, between January of 2000 and December of 2009. The patients will be divided in young (<40 years old) and elderly (40 years old or more) to be part of a comparative analysis of the global survival rate and the disease-free survival. Also, we will compare the histological kinds of neoplasm and the clinical staging at the moment of the diagnosis and its influence in the mortality rate in both groups. (AU)