Greene Frederick L, Stewart Andrew K, Norton H James
Department of General Surgery, Carolinas Medical Center, Charlotte, NC 28232-2861, USA.
J Clin Oncol. 2004 May 15;22(10):1778-84. doi: 10.1200/JCO.2004.07.015. Epub 2004 Feb 9.
The tumor-node-metastasis system for staging rectal cancer is based on invasion, number of involved nodes, and metastasis. Nodes are classified as N1 or N2 according to the number involved with metastases. Nodal positivity defines stage III regardless of depth of invasion or number of positive nodes. Our purpose was to analyze overall survival when node-positive patients were stratified into three new subsets.
We analyzed data entered into the National Cancer Data Base for 5,987 stage III patients with rectal cancer between 1991 and 1993. Survival was calculated using three new subgroups (IIIA: T1/2, N1; IIIB: T3/4, N1; IIIC: any T, N2). Survival following surgery and adjuvant therapy was assessed. The observed survival rates were calculated and compared using the log-rank method. The Cox regression model assessed subgroup differences.
Five-year observed survival rates for stage III subcategories were 55.1% in IIIA; 35.3% in IIIB; and 24.5% in IIIC. Stratifying for treatment outcome, stage IIIA patients having surgery alone (n = 278) had poorer observed 5-year survival (39%) than patients treated with surgery and adjuvant chemotherapy or radiation therapy (chemo/XRT; n = 765; 60%). Similar outcomes occurred in IIIB (surgery-alone [n = 726; 21.7%] and chemo/XRT [n = 2,130; 40.9%] groups) and in IIIC (surgery-alone [n = 467; 12.2%] and chemo/XRT [n = 1,621; 28.9%] groups). Differences were significant (P <.0001) in all stages.
The traditional stage III designation of rectal cancer fails to account for invasion (T1-4) and number of involved nodes (N1, N2). The stratification of stage III patients into three subsets should be used in future analyses of rectal cancer. The effect of postoperative adjuvant therapy was beneficial in all subsets.
直肠癌分期的肿瘤-淋巴结-转移系统基于肿瘤侵犯情况、受累淋巴结数量及有无转移。根据转移的淋巴结数量，将淋巴结分为N1或N2。无论肿瘤侵犯深度或阳性淋巴结数量多少，淋巴结阳性均定义为Ⅲ期。我们的目的是分析将淋巴结阳性患者分为三个新亚组时的总生存率。
我们分析了1991年至1993年间录入国家癌症数据库的5987例Ⅲ期直肠癌患者的数据。使用三个新亚组（ⅢA期：T1/2，N1；ⅢB期：T3/4，N1；ⅡIC期：任何T，N2）计算生存率。评估手术及辅助治疗后的生存率。使用对数秩检验计算并比较观察到的生存率。Cox回归模型评估亚组差异。
Ⅲ期各亚组的5年观察生存率分别为：ⅢA期55.1%；ⅢB期35.3%；ⅡIC期24.5%。按治疗结果分层，单纯手术的ⅢA期患者（n = 278）的5年观察生存率（39%）低于接受手术及辅助化疗或放疗（化疗/放疗；n = 765；60%）的患者。ⅢB期（单纯手术组[n = 726；21.7%]和化疗/放疗组[n = 2130；40.9%]）和ⅡIC期（单纯手术组[n = 467；12.2%]和化疗/放疗组[n = 1621；28.9%]）也出现了类似结果。各期差异均有统计学意义（P <.0001）。
直肠癌传统的Ⅲ期分类未考虑肿瘤侵犯情况（T1-4）和受累淋巴结数量（N1、N2）。Ⅲ期患者分为三个亚组的分层方法应在未来直肠癌分析中使用。术后辅助治疗对所有亚组均有益。
