Kaneko K, Fujii T, Kato S, Boku N, Oda Y, Koba I, Ohtsu A, Hosokawa K, Ono M, Shimoda T, Yoshida S
Department of Medicine, National Cancer Center Hospital East, Chiba, Japan.
Jpn J Clin Oncol. 1998 Mar;28(3):196-201. doi: 10.1093/jjco/28.3.196.
Recent Japanese studies have shown that histogenesis of small colorectal carcinomas can be divided into two groups: polypoid growth arising from polypoid neoplasia, and nonpolypoid growth arising from flat or depressed neoplasia. This classification should be verified with genetic as well as morphologic characteristics.
In order to classify our subject into polypoid growth and nonpolypoid growth types both histologically and endoscopically, we selected 42 colorectal carcinomas < 2 cm in size (35 submucosal and seven more advanced). Clinicopathological findings, presence or absence of Ki-ras gene mutation and overexpression of p53 protein were compared between the two types.
Histologically, the cases were divided into 27 of the polypoid growth type and 15 of the nonpolypoid growth type. None of the nonpolypoid growth cases contained adenomatous remnant, wheras this was found in 75% of the polypoid growth cases. No Ki-ras mutation was observed in any of the nonpolypoid growth cases, although it appeared in 44% of the polypoid growth cases. Regarding the overexpression of p53 protein, no significant difference was observed between the two types. The histological and the colonoscopic polypoid growth-nonpolypoid growth classifications correlated well with each other (agreement rate 98%), except for one lesion, which was classified as polypoid growth type endoscopically but as nonpolypoid growth type histologically.
The histologically defined polypoid growth-nonpolypoid growth classification may indicate a difference in pathway of colorectal carcinogenesis. Also, colonoscopic polypoid growth-nonpolypoid growth classification is available for preoperative estimation of the genetic characteristics of small carcinomas.
近期日本的研究表明，结直肠小癌的组织发生可分为两组：源于息肉样肿瘤的息肉样生长，以及源于平坦或凹陷性肿瘤的非息肉样生长。这种分类应通过遗传学和形态学特征进行验证。
为了从组织学和内镜学角度将我们的研究对象分为息肉样生长型和非息肉样生长型，我们选取了42例直径小于2 cm的结直肠癌（35例黏膜下癌和7例进展期癌）。比较了两种类型之间的临床病理特征、Ki-ras基因突变的有无以及p53蛋白的过表达情况。
组织学上，病例分为息肉样生长型27例和非息肉样生长型15例。非息肉样生长型病例均无腺瘤残留，而息肉样生长型病例中有75%存在腺瘤残留。非息肉样生长型病例均未观察到Ki-ras突变，而息肉样生长型病例中有44%出现该突变。关于p53蛋白的过表达，两种类型之间未观察到显著差异。组织学和结肠镜下息肉样生长 - 非息肉样生长分类彼此相关性良好（符合率98%），但有一个病变除外，该病变内镜下分类为息肉样生长型，而组织学上分类为非息肉样生长型。
组织学定义的息肉样生长 - 非息肉样生长分类可能表明结直肠癌发生途径存在差异。此外，结肠镜下息肉样生长 - 非息肉样生长分类可用于术前评估小癌的遗传特征。
