83 Evaluation of the 7th UICC TNM Staging System of Gastric Cancer the central region of the tumor. According to the 83th workshop of the Japanese Society for Gastric Cancer, on March 2011, “Pro- gresses in the diagnosis and treatment of the esophago-gastric junction tumors”, most Japanese surgeons considered an EG junc- tion carcinoma to be a gastric cancer rather than an esophageal cancer for treatment. According to Rausei et al.,(40) EG junction carcinoma was included in the esophageal chapter based on the new TNM staging system according to the anatomical criteria ‘5 cm rule’ proposed by Siewert but this was based on an obscure concept of the tumor epicenter. Accordingly in some cases, a gas- tric fundus tumor might also be considered as an esophageal can- cer. Therefore, the current revision did not clarify the clinical issues that are well known regarding the EG junction carcinoma. Never- theless, it did not discourage attempts to make a differentiation of an EG junction carcinoma from an esophageal or gastric cancer. Conclusions In the seventh edition of the UICC TNM staging, which has recently been revised, attempts were made to resolve the problems of previous editions of TNM staging. On the other hand, any noticeable matters have not been resolved. First of all, the N3 category was defined too extensively in the classification of lymph node metastasis. This achieved a simplification of the classification but it impaired the accuracy in predicting the prognosis in cases of progressive gastric cancer with a large number of lymph nodes with metastasis. Besides, it also did not clarify the minimum number of lymph nodes that should be dissected for appropriate TNM staging as shown previously. Therefore, it reduced the accuracy of TNM staging due to stage migration. Although it declared that it resolved the confusion of previous editions of TNM staging by specifying that the EG junction carcinoma should follow the classification system for esophageal cancer, it provided no clear evidence for this and did not resolve the previous issues. The edition also declared that positive cases to a peritoneal washing cytology should be considered a distant metastasis and then determined to be TNM stage IV. On the other hand, there are no standardized methods for this diagnostic regimen, which is not performed at many medical institutions, and deserves further consideration. The most ideal TNM staging methods should be composed of simpler rules so that it may be used easily in a clinical setting. Simultaneously, it should also guarantee the consistency between the cases corresponding to the same TNM stage and the differentiation between those corresponding to different TNM stages. This is quite challenging to surgeons. Further revisions of the TNM staging will be needed to contain both of these aspects to develop a harmonized classification. References 1. Sayegh ME, Sano T, Dexter S, Katai H, Fukagawa T, Sasako M. TNM and Japanese staging systems for gastric cancer: how do they coexist? Gastric Cancer 2004;7:140-148. 2. Ha TK, Kim HJ, Kwon SJ. Does the New UICC/AJCC TNM Staging System (7th Edition) Improve Assessing Prognosis in Gastric Cancer Compared to the Old System (6th Edition)? J Korean Gastric Cancer Assoc 2009;9:159-166. 3. Huang B, Zheng X, Wang Z, Wang M, Dong Y, Zhao B, et al. Prognostic significance of the number of metastatic lymph nodes: is UICC/TNM node classification perfectly suitable for early gastric cancer? Ann Surg Oncol 2009;16:61-67. 4. Qiu MZ, Wang ZQ, Zhang DS, Liu Q, Luo HY, Zhou ZW, et al. Comparison of 6th and 7th AJCC TNM staging classification for carcinoma of the stomach in China. Ann Surg Oncol 2011 Jan 19. [Epub ahead of print] 5. Deng J, Liang H, Sun D, Wang D, Pan Y. Suitability of 7th UICC N stage for predicting the overall survival of gastric can- cer patients after curative resection in China. Ann Surg Oncol 2010;17:1259-1266. 6. Deng J, Liang H, Wang D. The feasibility of N stage of the 7th edition TNM for gastric cancer. Ann Surg Oncol 2011;18:1805- 1806. 7. Bae JM, Kim SW, Kim SW, Song SK. Evaluation of prognostic values according to the new TNM classification in gastric can- cer. J Korean Surg Soc 2011;80:23-28. 8. Deng JY, Liang H, Sun D, Zhan HJ, Wang XN, The appropriate cutoffs of positive lymph nodes to evaluate the prognosis of gastric cancer patients. J Surg Oncol 2008;98:343-348. 9. Bunt AM, Hermans J, Smit VT, van de Velde CJ, Fleuren GJ, Bruijn JA. Surgical/pathologic-stage migration confounds comparisons of gastric cancer survival rates between Japan and Western countries. J Clin Oncol 1995;13:19-25. 10. Hundahl SA, Phillips JL, Menck HR. The National Cancer Data Base Report on poor survival of U.S. gastric carcinoma patients treated with gastrectomy: fifth edition American Joint Committee on Cancer staging, proximal disease, and the ‘‘dif- ferent disease’’ hypothesis. Cancer 2000;88:921-932. 11. Barbour AP, Rizk NP, Gonen M, Tang L, Bains MS, Rusch