J Korean Surg Soc JKSS Journal of the Korean Surgical Society 1226-0053 The Korean Surgical Society 10.4174/jkss.2009.77.4.257 Original Article The Analysis of Clinical Characteristics of pT2a and pT2b Gastric Cancer Choi Byoung Hyun M.D. Kim Ji Hoon M.D. 1 Kwak Jin Ho M.D. 1 Jang Hyuck Jae M.D. 1 Han Myung Sik M.D. 1 Department of Surgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea. Department of Surgery, Gangneung Asan Hospital, University of Ulsan College of Medicine, Gangnueng, Korea. Corresponding author (cibax@gnah.co.kr) 10 2009 30 09 2009 77 4 257 261 26 03 2009 08 07 2009 Copyright © 2009 The Korean Surgical Society 2009 Purpose

T2 gastric cancer is tumor invading proper muscle or subserosal layer. The 2002 American Joint Committee on Cancer subdivided the pT2 gastric adenocarcinoma into a type pT2a (invasion of the proper muscle) and a type pT2b (invasion of the subserosa). The aim of this study was to evaluate the differences between pT2a and pT2b gastric cancers of the clinicopathological features and the prognostic factors.

 Methods

A series of curative operations were performed on 194 patients with pT2 gastric cancer from January 1999 to February 2006. We reviewed, retrospectively, the clinicopathologic characteristics, the 3-year disease free survival and the 5-year disease specific survival rates.

 Results

There were significant clinicopathologic differences between pT2a and pT2b gastric cancer in tumor size and the number of metastatic lymph nodes. Both of the 3-year disease free survival time and the 5-year disease specific survival time were much longer for the pT2a gastric carcinoma patients than those for the pT2b gastric carcinoma patients.

 Conclusion

It is important to consider the differences between pT2a and pT2b gastric cancers for prediction of recurrence or prognosis. Furthermore, new staging of pT2a and pT2b cancer may be necessary.

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Comparison of overall survival for patients with pT2a and pT2b gastric cancer. The overall survival of pT2a group is 83.3% and that of pT2b is 65.6% (P=0.009).

Comparison of disease free survival for patients with pT2a and pT2b gastric cancer. The 3-year disease free survival of pT2a group is 88.1% and that of pT2b is 73.2% (P=0.022).

Comparison of disease-specific survival for patients with pT2a and pT2b gastric cancer. The 5-year disease-specific survival of the pT2a group is 85.0% and that of pT2b group is 70.3% (P=0.022).

Clinicopathological characteristics of pT2a and pT2b gastric cancer patients

*WD = well differentiated; †MD = moderate differentiated; ‡PD = poorly differentiated; §SRC = signet ring cell; ∥MUC = mucinous; Missing data in 8 cases; **Missing data in 6 cases.