Zhonghua Zhong Liu Za Zhi. 2021 Nov 23;43(11):1197-1202. doi: 10.3760/cma.j.cn112152-20200309-00189.
ABSTRACT
Objective: To investigate the clinical value of pT2 gastric cancer staging pT2a and pT2b according to the depth of muscularis propria invasion in evaluating the prognosis of gastric cancer. Methods: According to the 8th edition of TNM staging system for gastric cancer proposed by the Union for International Cancer Control (UICC) and the American Joint Committee on Cancer (AJCC), patients with gastric cancer who underwent radical surgery in the Fourth Hospital of Hebei Medical University from January 1, 2008 to January 1, 2015 were selected and divided into pT2a and pT2b stage group according to the depth of tumor invasion. The 5-year overall survival (OS) and disease-free survival (DFS) were compared between the two groups. Results: The median follow-up time of 1 411 patients with postoperative pathological pT2 stage was 68.8 months, and 1 347 patients (95.46%) received complete follow-up data. The 5-year OS rate was 65.85%, and the 5-year DFS rate was 67.83 %. The 5-year OS rate and 5-year DFS rate of 709 pT2a patients were 72.50% and 73.91%, respectively. The 5-year OS rate and 5-year DFS rate of 638 pT2b patients were 58.46% and 61.13%, respectively, significantly different from those of the pT2a group (P<0.001). Hierarchical analysis was performed according to N staging. The 5-year OS rates of pT2aN0M0 (274 cases), pT2aN1M0 (192 cases), pT2aN2M0 (147 cases), pT2aN3aM0 (59 cases) and pT2aN3bM0 (37 cases) were 83.58 %, 72.40 %, 68.71 %, 54.24 % and 35.12 %, respectively. The 5-year DFS rates were 84.67 %, 77.08 %, 67.35 %, 54.24 % and 35.14 %, respectively. In the pT2b group, the 5-year OS rates of pT2bN0M0 (209 cases), pT2bN1M0 (166 cases), pT2bN2M0 (127 cases), pT2bN3aM0 (78 cases) and pT2bN3bM0 (58 cases) were 76.08%, 62.05%, 56.69%, 37.18% and 17.24%, respectively, and the 5-year DFS rates were 80.86%, 69.28%, 54.33%, 35.90% and 15.52%, respectively. Under the same N stage, the OS rates of patients in the pT2a group were better than those in the pT2b group (P values were 0.023, 0.034, 0.034, 0.043 and 0.018, respectively). When the N stage was N0 and N1, there was no significant difference in the 5-year DFS rate between the pT2a group and the pT2b group (P values were 0.199 and 0.090, respectively). When the N stages were N2, N3a and N3b, the difference between the pT2a stage group and the pT2b stage group was statistically significant (P values were 0.027, 0.022 and 0.025, respectively). Conclusions: In the 8th edition of AJCC/UICC gastric cancer staging system, pT2 stage can be divided into pT2a stage (invasion of superficial muscularis) and pT2b stage (invasion of deep muscularis) according to the infiltration depth of muscularis propria. There are significant differences in prognosis between the two groups. Combined with the number of lymph node metastasis, the prognosis of patients with pT2 gastric cancer can be more accurately evaluated.
PMID:34794224 | DOI:10.3760/cma.j.cn112152-20200309-00189