Since 1966, we have continued gastric mass survey by indirect fluororadiography and endoscopic workup in a model town of Misumi. In 1973 we started abdominal ultrasonic survey combined with gastric mass survey. And since 1993, I have undergone managed survey by endoscopic examination. Looking back the long 40 years of regional gastric mass survey, I have investigated the future method of gastric mass survey.
1) The detection rate of gastric cancer was 0.22%, and 46% of those found were early gastric cancer. Those rates were similar to those of regional gastric mass survey in Yamaguchi prefecture.
2) Considering the accuracy and the economic efficiency, gastroendoscopic examination is recommended. In advance of gastric extermination, it is desirable to identify the high risk group PG method and measured HP, and separate them into two groups, one is indirect fluororadiography examination, the other is direct gastroendoscopic examination group.
3) The abdominal ultrasonic survey combined with gastric mass survey is becoming attractive for examinees. More people are taking the examination, which is leading to a detection of early cancer in many organs.
4) Since 1993, I have continued the managed survey by endoscopic examination. During the 14 years, I have founded 14 cases (4.8%) of early cancer, including 3 cases of esophageal cancer, among 290 examinees and 5 were treated by ESD.

View full abstract

Although it has been a long time since the method of screening gastric cancer was changed from X-ray examination to endoscopy in Japanese institutions, we have not found any reports which prove the actual decrease in the rate of gastric cancer death as a result of employing endoscopy. Consequently, endoscopy was not recommended as a population-based screening method for gastric cancer in the guidelines published in 2006.
The aim of this study was to evaluate the decrease in the rate of gastric cancer death as a result of employing endoscopy, based on the accurate records kept by the population-based regional cancer registries. Among the 4889 cases used in our statistical study, all of whom were older than 50 years of age and were examined in 1993 by gastric endoscopy, 2310 were reexamined from 1994 to 1996 and were not diagnosed with gastric cancer. However, 2579 were not reexamined within that time period. We compared these 4889 cases with the population-based cancer registry of Fukui Prefecture, which is the most accurate in Japan.
In the reexamined group, 40 patients were diagnosed as having gastric cancer after 1997, and two patients died of gastric cancer. In the non-reexamined group, 49 patients were diagnosed as having gastric cancer, and eleven patients died of gastric cancer. The cumulative 5-year death rate (Kaplan-Meier procedure) was 5.1% and 24.7% in the reexamined group and the non-reexamined group, respectively (p<0.05); significant differences between these two groups were observed. The odds ratio of death from gastric cancer for the reexamined patients was 0.20 (95% confidence interval, 0.04-0.91) compared to that for the non-reexamined patients.
It is suggested that repeated endoscopy might reduce the mortality of gastric cancer by 80%, but a long time must elapse after the examinations to observe any real reduction in the mortality rate.

View full abstract

There are gene polymorphisms which influence the production quantity of some cytokines. It has also been reported that certain cytokines participate in the onset of gastric cancer. It is reported that interleukin-1 beta (IL-1b) gene polymorphisms and interleukin-1 receptor antagonist (IL-1RN) gene polymorphisms are particularly associated with increased risk of gastric cancer. Furthermore, polymorphisms in the gene for cytochrome P-450 (CYP2C19), which is a representative drug-metabolizing hepatic enzyme, are known to influence pharmacokinetics and pharmacodynamics. It is reported that CYP2C19 participates in the onset of cancer in the esophagus, lung and liver. However, there are few reports that CYP2C19 participates in the onset of gastric cancer. At present, persons which test positive with the serum pepsinogen (PG) method (cutoff value: lower than PG I 70ng/ml and lower than PG I/II rate 3.0) are considered to belong to the high-risk group for gastric cancer. In the current study, we examined IL-1B and CYP2C19 polymorphisms using multivariate analysis in order to better select high-risk cases during gastric cancer examination. We screened 228 subjects for gastric cancer [male ratio: 0.84; mean age: 45.8 +/- 0.6 years]. The serum anti-H. pylori IgG antibody level and the presence of the IL-1B-511 polymorphism were factors which clearly differed between the low-risk group and the high-risk group, not the serum anti-H. pylori IgG antibody level or the presence of the CYP2C19 polymorphism. In the multivariate analysis of these factors, the odds ratio of the serum anti-H. pylori IgG antibody was 70.9, and that of the IL-1B-511 polymorphism was 2.50 (i.e., the ratio between the C/C genotype and the C/T or T/T genotype). Based on our findings described above, we were able to predict cases of atrophic gastritis, which tended to develop further due to the infection by H. pylori, based on the presence of the IL-1B-511 polymorphism as easily as with the PG method. Thus, the use of the IL-1B-511 polymorphism together with the PG method will enable us to more accurately select high-risk cases of gastric cancer. However, we believe that further study of this combined IL-1B and CYP2C19 polymorphism examination method is necessary.

View full abstract

The cases of colorectal cancer discovered in individual screening performed in the Omiya district of Saitama City were divided by assay values determined from fecal occult blood tests into 5 groups: a)110-199, b)200-299, c)300-399 ,d)400-499, and e)500∼ng/ml , and the rates of cases which required close examination were reviewed to explore the possibility of failing to discover colorectal cancer distributed in each group according to the cut-off assay values.
Of the 1,159 cases of colorectal cancer discovered, 447 cases were with sm or deeper invasion, and 54 cases (12.1%) were in group a) and 317 cases (70.9%) were in group e). There was a higher number (rate) of cases discovered with higher assay values, but more than a few cases were also discovered in group a). In these circumstances, if the cut-off value of 110 ng/ml is changed to 200 ng/ml, the rate of cases requiring close examination would be reduced from 9.02% to 4.71%, but 54 cases (12.1%) of cancer with sm or deeper invasion (of which 24 cases were with mp or deeper invasion) in group a) would become false-negative and thus be missed.
While the individuals who seek colorectal cancer screening have exceeded 35,000 in number in recent years, there has been no significant change in the number who require close examination, and in fact the rate of cases prescribed to require close examination has been showing a tendency to decrease gradually.
In order to optimize the rate of cases that require close examination, it seemed important to perform screening using the present cut-off values and analyze the cases of cancer discovered while making an effort to increase the number of individuals who seek screening and the rate of those who seek close examination.

View full abstract

We evaluated upper abdominal screening using ultrasonography by calculating the observed survival rate (Kaplan-Meier method) and the 1- to-5-year relative survival rates in patients with liver, biliary tract, pancreatic and renal cancers detected during ultrasonographic mass screenings. As controls, we used patients with liver, biliary tract, pancreatic and renal cancers detected at the outpatient clinic of the Miyagi Cancer Center.
Although ultrasonographic screening was not effective in reducing the mortality rate of hepatocellular carcinoma, it improved the observed and relative survival rates to the same degree as the medical management of the high-risk hepatocellular carcinoma group. As for the patients with biliary tract cancer, some patients might have a better chance of long survival as a result of ultrasonographic screening, but it was impossible to evaluate the efficacy of the screening in this case because of the small number of patients. Ultrasonographic screening was not effective in either reducing the mortality rates in patients with pancreatic cancer or improving their outcome. Although the observed survival rate in patients with renal cell carcinoma detected during ultrasonographic screening was significantly better for up to 13 years after the cancer detection, the cancer recurrence rate in patients more than 13 years after the cancer detection was high and the survival rate was low.

View full abstract