Sasaki S, Masaki T, Umetani N, Shinozaki M, Yokoyama T, Ono M, Nagawa H, Muto T
Department of Surgery, University of Tokyo, Japan.
Jpn J Clin Oncol. 1998 Jul;28(7):427-30. doi: 10.1093/jjco/28.7.427.
The management of patients with multiple colorectal adenomas, 10-100 in number, is often troublesome clinically. To establish the reasonable management of such cases, genetic backgrounds should be made clear.
For a total of 19 adenomas and four carcinomas from four patients with multiple colorectal adenomas, we analyzed genetic instability at four selected microsatellite loci and screened exon 1-4 of the APC gene with special reference to macroscopic configurations of adenomas and carcinomas.
RER-positive phenotypes were detected in none of 13 protruded type adenomas, two (33%) out of six superficial elevated type adenomas and two (50%) out of four carcinomas. We detected no mutation of exon 1-4 of the APC gene in any sample. In patients with multiple colorectral adenomas, the proportion of superficial elevated type adenomas exhibiting genetic instability was significantly higher than that of protruded type adenomas.
The results suggested that RER-positive phenotype was an early event in tumorigenesis through superficial elevated type adenomas.
临床上，对患有10至100个多发性结肠直肠腺瘤的患者进行管理往往很棘手。为了确立对此类病例的合理管理，应明确其遗传背景。
对于来自4例多发性结肠直肠腺瘤患者的总共19个腺瘤和4个癌，我们分析了4个选定微卫星位点的遗传不稳定性，并特别参照腺瘤和癌的宏观形态，筛查了APC基因的第1至4外显子。
在13个隆起型腺瘤中未检测到RER阳性表型，6个表面隆起型腺瘤中有2个（33%）检测到，4个癌中有2个（50%）检测到。在任何样本中均未检测到APC基因第1至4外显子的突变。在多发性结肠直肠腺瘤患者中，表现出遗传不稳定性的表面隆起型腺瘤的比例显著高于隆起型腺瘤。
结果表明，RER阳性表型是通过表面隆起型腺瘤发生肿瘤的早期事件。
