Hayakawa M, Shimokawa K, Kusugami K, Sugihara M, Morooka Y, Fujita T, Nakamura M, Nishio Y, Maeda K, Ando T, Peek R M
Department of Gastroenterology, Meitetsu Hospital, Nagoya, Japan.
Am J Gastroenterol. 1999 Apr;94(4):944-9. doi: 10.1111/j.1572-0241.1999.991_n.x.
We performed this study to analyze the endoscopic findings, dissecting microscopic features, and p53 immunostaining in superficial depressed-type (depressed) colorectal neoplastic lesions.
Dissecting stereomicroscopy was used to ascertain the size and pit pattern of lesions removed by endoscopic snare polypectomy. Immunohistochemical staining of p53 was performed with an antigen retrieval system using a monoclonal antibody to p53.
All depressed neoplastic lesions (submucosal carcinoma, n = 6; high-grade dysplasia, n = 14; and adenoma, n = 30) were small (< 1 cm in diameter) and were detected as a depression with or without a marginal elevation on colonoscopic examination. In the dissecting microscopic study, submucosal carcinomas and lesions of high-grade dysplasia almost exclusively showed irregular small pits, with the exception of four malignant lesions with moderate submucosal invasion in which the pit structure was absent. In contrast, adenomas had either regular small (29/30 lesions) or oval pits (1/30 lesions). Rates of p53 positivity were 100%, 64%, and 7% in depressed submucosal carcinomas, lesions of high-grade dysplasia, and adenomas, respectively, thus the prevalence of p53 positivity was significantly higher in the former two groups than in the adenoma group.
The high frequency of invasive carcinoma and high-grade dysplasia found in depressed colorectal neoplastic tumors, despite their small size, indicates that these lesions may be a subtype of colorectal tumor with more aggressive malignant potential at an earlier stage.
我们开展本研究以分析浅表凹陷型（凹陷型）结直肠肿瘤性病变的内镜检查结果、解剖显微镜特征及p53免疫染色情况。
采用解剖体视显微镜确定经内镜圈套息肉切除术切除的病变的大小和凹陷模式。使用针对p53的单克隆抗体通过抗原修复系统进行p53的免疫组织化学染色。
所有凹陷型肿瘤性病变（黏膜下癌，n = 6；高级别异型增生，n = 14；腺瘤，n = 30）均较小（直径<1 cm），在结肠镜检查中表现为有或无边缘隆起的凹陷。在解剖显微镜研究中，黏膜下癌和高级别异型增生性病变几乎均表现为不规则小凹陷，4例有中度黏膜下浸润的恶性病变除外，其凹陷结构消失。相比之下，腺瘤有规则的小凹陷（29/30例病变）或椭圆形凹陷（1/30例病变）。凹陷型黏膜下癌、高级别异型增生性病变和腺瘤的p53阳性率分别为100%、64%和7%，因此前两组的p53阳性率显著高于腺瘤组。
凹陷型结直肠肿瘤性病变中侵袭性癌和高级别异型增生的高发生率，尽管其体积较小，表明这些病变可能是结直肠肿瘤的一种亚型，在早期具有更强的侵袭性恶性潜能。
