81 Evaluation of the 7th UICC TNM Staging System of Gastric Cancer of the survival rate in stage IV cases was strengthened. Of the total M0 cases, no stage IV was determined in cases in whom both the degree of invasion to the gastric wall and that of a lymph node metastasis were relatively higher. The difference in the survival rate from stage IV would not be of statistical significance. As mentioned previously, highly-advanced T4b cases in whom the number of lymph nodes with a metastasis was greater than 30 were not classified as stage IV provided there was M0. Compared to the cases in whom stage IV was determined, a poorer prognosis was found. In these cases, a more advanced classification system is needed. Another classification system is a revision that positive cases to a peritoneal washing cytology are classified as a distant metastasis. There are various methods for performing a peritoneal washing cytology. Depending on the types of methods, there is a large discrepancy in the frequency of a positive cytology (cy+). According to Kodera et al.,(26) the rate of positive cases was found ＞20% on a routine cytology, 35% on immunohistochemistry and 50% on RT-PCR in cases of a serosa invasion-positive gastric carcinoma. In addition, there is a large discrepancy in the positive rates and median survival time (MST) of the positive cases between institutions. At the East Hospital of National Cancer Center of Japan, the positive rate and MST were 14% and 12 months, respectively, in cases of invasion to the subserosal layer or deeper (n=924). At the Central Hospital of National Cancer Center of Japan,(27) the positive rate and MST were 22.6% and 12 months, respectively, in cases of invasion to the muscular layer or deeper (n=996). At the MD Anderson Cancer Center in the USA,(28) the positive rate was 10.2% in cases of T1~T4b (n=381). After classifying these cases into the neoadjuvant chemotherapy group and non-neoadjuvant chemotherapy group, the MST was found to be 13 months and 7 months, respectively. According to reports from the Queen Elizabeth Hospital in the UK,(29) in 207 cases of T3 and T4a, the positive rate and MST were 7.2% and 13 months, respectively. Indeed, a peritoneal washing cytology is not a diagnostic regimen that is commonly performed at most hospitals. Accordingly, there should be guidelines for recording whether a cytology was performed, e.g. CYX. On the seventh edition of the UICC TNM staging system, positive cases to a peritoneal washing cytology are classified as a distant metastasis, except for which there are no definite guidelines for recording whether the cytology should be performed. Accordingly, if there are any positive cases in whom a peritoneal washing cytology was not performed and there was no concurrent presence of other lesions of a distant metastasis, these cases are not classified as stage IV. This might cause problems in establishing consistency between the TNM stages. According to the methods of the tests and because of the variability in the interpretation of test results, further revisions will be needed to examine whether a peritoneal washing cytology can be classified as a distant metastasis. The TNM Staging in the EG Junction Carcinoma According to Washington,(30) because there is variability in the prognosis of gastric cancer depending on the anatomical location at the sites of occurrence, cancers at the distal sites have a better prognosis. Accordingly, there is the possibility that the classification system developed the most appropriately for cancers at the distal sites might not be the best TNM staging. Accordingly, in an effort to improve the staging system for gastric cancer, only when the data obtained from Asians and Caucasians are referenced can the classification be applied from a worldwide perspective. In particular, regarding cases of the EG junction carcinoma, according to the sixth edition, based on the judgment of the physicians, classifica- tions into the esophageal cancer or gastric cancer should be made. In the seventh edition, however, the primary goal of revisions to the TNM staging was to clear this confusion. The secondary goal is to homogenize the tumor (T) category for cases of gastrointestinal tumors occurring at the gastrointestinal (GI) tract extending from the stomach, small intestine and large intestine to the rectum. Therefore, attempts were made to simply the concept of the T- category, which is one of the essential factors for the classification of TNM stage. To achieve these goals, it was declared that the clas- sification system for esophageal cancer be followed in cases of EG junction carcinoma and the previous confusion was resolved ac- cordingly. On the other hand, there is no evidence demonstrating the validity of the application of the classification system for esophageal cancer rather than stomach cancer. Besides, there are reports that the same T category should be applied to all cancers occurring at this site because the GI tract is formed of a single tu- bular structure. On the other hand, this would be problematic be- cause the anatomical difference between the organs was not con- sidered. According to Hassan et al.,(31) the incidence of gastric cardia adenocarcinoma was increased with time and increased gradually to 42% of the total cases of gastric cancer in 1996. Clark et al.(32) reported that the incidence of cardia cancer and that of distal esophageal adenocarcinoma in Caucasians had increased. This led to the speculation that both disease entities have the same