In Haejin, Kantor Olga, Sharpe Susan M, Baker Marshall S, Talamonti Mark S, Posner Mitchell C
Department of Surgery, The University of Chicago, Chicago, IL, USA.
Department of Surgery, Montefiore Medical Center, Bronx, NY, USA.
Ann Surg Oncol. 2016 Jun;23(6):1956-62. doi: 10.1245/s10434-015-5075-1. Epub 2016 Jan 11.
The benefit of adjuvant therapy following resection of early stage, node-negative gastric adenocarcinoma following a margin negative (R0) resection is unclear.
The National Cancer Data Base was used to identify patients with a T2N0 gastric adenocarcinoma (tumor invasion into the muscularis propria) who underwent R0 resection. Patients treated with neoadjuvant therapy and those for whom lymph node count was unavailable were excluded from the analysis. Kaplan-Meier and Cox regression were used to evaluate differences in and predictors of overall survival.
A total of 1687 patients underwent R0 resection for T2N0 gastric adenocarcinoma between 2003-2011. Adjuvant chemotherapy treatment was administered to 7.1 and 14.1 % received adjuvant chemoradiation; 65.4 % had <15 lymph nodes examined. Multivariate Cox regression identified higher Charlson score, <15 lymph nodes examined, higher tumor grade, and tumor location in the cardia as factors associated with significantly decreased overall survival. With a median follow-up of 36 months, the 5-year overall survival was 71 % for patients with ≥15 lymph nodes examined and 53 % for those with <15 lymph nodes (p < 0.001). In patients who had <15 lymph nodes examined, there was an overall survival benefit for adjuvant chemoradiation (hazard ratio 0.71, p = 0.043). In patients with ≥15 lymph nodes examined, no survival benefit for adjuvant therapy was identified (p > 0.74).
Adequate lymph node dissection and pathologic staging is critical in directing optimal treatment of patients with early gastric cancer. Understaging as a result of suboptimal lymphadenectomy may explain the perceived benefit of adjuvant chemoradiation after an R0 resection for T2N0 gastric cancer.
早期、淋巴结阴性的胃腺癌在切缘阴性（R0）切除术后辅助治疗的获益尚不清楚。
利用国家癌症数据库识别接受R0切除的T2N0胃腺癌（肿瘤侵犯固有肌层）患者。接受新辅助治疗的患者以及淋巴结计数不可用的患者被排除在分析之外。采用Kaplan-Meier法和Cox回归分析评估总生存的差异及预测因素。
2003年至2011年间，共有1687例患者接受了T2N0胃腺癌的R0切除。7.1%的患者接受了辅助化疗，14.1%接受了辅助放化疗；65.4%的患者检查的淋巴结<15枚。多因素Cox回归分析显示，较高的Charlson评分、检查的淋巴结<15枚、较高的肿瘤分级以及肿瘤位于贲门部是总生存显著降低的相关因素。中位随访36个月，检查的淋巴结≥15枚的患者5年总生存率为71%，检查的淋巴结<15枚的患者为53%（p<0.001）。在检查的淋巴结<15枚的患者中，辅助放化疗有总生存获益（风险比0.71，p=0.043）。在检查的淋巴结≥15枚的患者中，未发现辅助治疗有生存获益（p>0.74）。
充分的淋巴结清扫和病理分期对于指导早期胃癌患者的最佳治疗至关重要。因淋巴结清扫不充分导致分期过低可能解释了T2N0胃癌R0切除术后辅助放化疗的获益。
