Gastrointestinal and Liver Pathology Research Laboratory, Department of Pathology, Karolinska Institute and University Hospital, 17176, Stockholm, Sweden.
Anticancer Res. 2013 Dec;33(12):5471-6.
Colorectal carcinoma, the third most commonly diagnosed type of cancer in Europe and the USA, usually originates from colorectal adenoma (CRA). Three main histological phenotypes of CRA are usually recognized: tubular, villous and traditional serrated (TA, VA and TSA, respectively). In 1997, we reported a novel histological phenotype, the microtubular adenoma (MTA), epitomized by dysplastic epithelium arranged in closed rings (microtubules), with sideways-elongated outgrowth.
The material includes 4,446 CRAs diagnosed at our Department during a 10-year period (2001-2010).
Out of 4,446 CRAs, 68 (1.5%) were MTA; of these, 38 (55.9%) exhibited low-grade dysplasia (LGD), 17 (25.0%), high-grade-dysplasia, two (2.9%) intraepithelial carcinoma and three (4.4%), intramucosal carcinoma. Out of the 68 MTA, 22 (32.3%) were advanced MTA. Submucosal carcinoma (SMC) was present in eight (11.8%) MTAs. Ninety-four per cent (64/68) of the MTAs were left-sided adenomas. In previous work, we found that cell proliferation occurred in the dysplastic microtubules in MTA, initially in the luminal dysplastic epithelium in TA and VA, and initially at the bottom of the serrated dysplastic crypts in TSA.
Due to these distinctive microscopic and cell proliferative attributes, a predominant left-sided location and the absence of serrated configurations, it is submitted that MTA is a specific CRA phenotype, at variance with TA, VA, and TSA. The high frequency of SMC strongly suggests that MTA is an important alternative pathway in colorectal carcinogenesis.
结直肠癌是欧洲和美国第三大常见的癌症类型，通常起源于结直肠腺瘤（CRA）。CRA 通常有三种主要的组织学表型：管状、绒毛状和传统锯齿状（TA、VA 和 TSA，分别）。1997 年，我们报告了一种新的组织学表型，即微管状腺瘤（MTA），其特征为排列成封闭环（微管）的异型上皮，侧向伸长。
该材料包括我们科室在 10 年期间（2001-2010 年）诊断的 4446 例 CRA。
在 4446 例 CRA 中，有 68 例（1.5%）为 MTA；其中，38 例（55.9%）为低级别异型增生（LGD），17 例（25.0%）为高级别异型增生，2 例（2.9%）为上皮内癌，3 例（4.4%）为黏膜内癌。在 68 例 MTA 中，有 22 例（32.3%）为高级 MTA。在 8 例（11.8%）的 MTA 中存在黏膜下癌（SMC）。94%（64/68）的 MTA 为左侧腺瘤。在之前的研究中，我们发现 MTA 中的异型增生微管存在细胞增殖，最初在 TA 和 VA 的管腔异型增生上皮中，最初在 TSA 的锯齿状异型增生隐窝底部。
由于这些独特的微观和细胞增殖特征，主要位于左侧，且无锯齿状形态，因此认为 MTA 是一种特定的 CRA 表型，与 TA、VA 和 TSA 不同。SMC 的高频率强烈提示 MTA 是结直肠癌变的一个重要替代途径。
