Kobayashi Hirotoshi, Ueno Hideki, Hashiguchi Yojiro, Mochizuki Hidetaka
Department of Surgery I, National Defense Medical College, Saitama, Japan.
Surgery. 2006 Apr;139(4):516-22. doi: 10.1016/j.surg.2005.09.004.
In the TNM classification of colorectal carcinoma, N-staging is dependent on the number of metastases; in the Japanese classification system, staging usually has been based on the distribution of metastases (N1, paracolic; N2, along the major vessels; N3, at the root of major vessels). The aim of our study was to examine whether the concept of the distribution of nodal metastasis could improve the TNM classification for colorectal cancer.
We studied the survival rates of 485 and 136 patients with stage III colonic and rectal cancer, respectively, who underwent curative surgery between 1979 and 1998. The patients were categorized into 4 groups: group 1, TNM-N1 classified in J-N1; group 2, TNM-N2 in J-N1; group 3, TNM-N1 in J-N2-3; and group 4, TNM-N2 in J-N2-3.
In the colon cancer arm, the 5-year survival rates of the patients in groups 1 to 4 were 74%, 51%, 52%, and 54%, respectively. There was a significant difference in survival rate between groups 1 and 3 (P = .0002). Thus, in colon cancer, nodal metastasis along the major vessels was a bad prognostic factor, even though the number of nodes that were involved was <4. In the rectum cancer arm, the 5-year survival rates of the patients in each group were 65%, 39%, 60%, and 32%, respectively. Only the number of nodal metastases was an independently significant prognostic variable.
This study suggests that adding the concept of nodal distribution to the conventional TNM staging of colon cancer will improve the accuracy in the evaluation of the nodal status.
在结直肠癌的TNM分类中，N分期取决于转移灶的数量；在日本的分类系统中，分期通常基于转移灶的分布（N1，结肠旁；N2，沿主要血管；N3，在主要血管根部）。我们研究的目的是检验淋巴结转移分布的概念是否能改善结直肠癌的TNM分类。
我们分别研究了1979年至1998年间接受根治性手术的485例III期结肠癌患者和136例III期直肠癌患者的生存率。患者被分为4组：第1组，TNM-N1分类为日本分类的N1；第2组，TNM-N2分类为日本分类的N1；第3组，TNM-N1分类为日本分类的N2-3；第4组，TNM-N2分类为日本分类的N2-3。
在结肠癌组中，第1至4组患者的5年生存率分别为74%、51%、52%和54%。第1组和第3组的生存率有显著差异（P = .0002）。因此，在结肠癌中，即使受累淋巴结数量<4，沿主要血管的淋巴结转移也是一个不良预后因素。在直肠癌组中，每组患者的5年生存率分别为65%、39%、60%和32%。只有淋巴结转移数量是一个独立的显著预后变量。
本研究表明，在结肠癌的传统TNM分期中增加淋巴结分布的概念将提高淋巴结状态评估的准确性。
