Controversy in Gastric cancer

As one reflect on the epidemiology of Gastric cancer, one ends up with questions that are technically answered in the main stream scientific reporting but lead to the following questions in the scientific researcher mind.
1. It is generally accepted as a fact that there is a 75% decrease of Gastric Cancer in the United states over the last few decades.  The official reason is that there has been a significant improvement in food storage and quality of water.  This conclusion is not really clearly based on gene evolution studies or any hard scientific data, it is based on observational evaluation that  poor people living in poor countries still have Gastric Cancers.  This assertion goes on unchallenged even though statistical evaluation in poor countries are notoriously unreliable or non-existent. The Peculiarity of the incidence of this disease in Japan challenges both the notions that poverty and unhealthy conditions  are the dominant forces leading to the disease.  Until all aspects are scientifically explored statements such as "gastric cancer is strongly influenced by nutritional, socio-economic, and medical factor rather than dominated by genetic" call for a pause!  The mere fact that there are twice as many men with gastric cancer than women partially challenges the statement.  And further more incidence variation is seen among the races (and ages).
2.The gastric cancer treated in Japan appears to have a better prognosis.  This fact has been "attributed to the superiority of surgical techniques".  The non adoption of such techniques elsewhere fly against that perception.  There is a lingering feeling that this cancer in the Japanese population is peculiar somehow.  That this peculiarity is the true reason of the good prognosis.  That is, the surgical technique is not fully the reason.  That feeling leaves western surgeons room to continue their current practice.  Indeed it would have been legally unacceptable to do less surgery when the more extensive "is better".

3.The use of Aspirin and non steroidal is associated lower cancer of the G-E junction.  This is contrary to what one would expect.  A medication causing gastric ulcer is in this case protective!

4.H. Pylori has been clearly demonstrated to lead to gastric cancer.  However its eradication is now only indicated for those with an Ulcer.  Why not eradicate all together, a vaccine campaign for example.  Scientist are not sure because "no definitive evidence shows that mass eradication could reduce the incidence" of this disease.  A mass Chinese study reportedly did not achieve such an objective .

WE HAVE GOT TO STUDY GENES AND THEIR DISPARITIES IN RACES MORE THOROUGHLY BEFORE MAKING DEFINITIVE BETTER CONCLUSION!