Electrocautery snare resection stimulates cellular proliferation of residual colorectal tumor
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PURPOSE: Recently, endoscopic mucosal resection has been performed commonly for colorectal tumors. However, incomplete endoscopic mucosal resection produces a residual tumor that grows rapidly. The aim of this study was to clarify the characteristics of the residual tumor using the nude mouse model. METHODS: Human colon cancer cells (colo201 or colo320DM) were implanted subcutaneous into nude mice. We then removed more than one-half of the tumor with an electrocautery snare or a surgical knife, and compared the tumor growth rate with that of control tumors. Before and after resection, we examined the Ki-67 labeling index of the tumors with an immunohistochemical assay and mRNA expression for epidermal growth factor receptor, vascular endothelial growth factor, and transforming growth factor alpha. RESULTS: Residual tumors showed a higher growth rate in tumor volume than control tumors using both methods (electrocautery snare and surgical knife). Colo201 groups showed a higher total volume change per day than colo320DM groups after resection. Furthermore, these tumors also showed a higher Ki-67 labeling index, and a stronger epidermal growth factor receptor and transforming growth factor alpha mRNA expression than primary and control tumors in the colo201 implanted groups. There was no significant difference in vascular endothelial growth factor mRNA expression between groups implanted with colo201 or colo320DM. CONCLUSION: Our results suggest that residual tumors caused by incomplete endoscopic mucosal resection may have a higher growth potential than the tumors before resection.
Key wordsResidual colorectal cancer Cellular proliferative activity Endoscopic treatment
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- 2.Bedogni G, Bertoni G, Ricci E,et al. Colonoscopic excision of large and giant colorectal polyps: technical implications and results over eight years. Dis Colon Rectum 1986;29:831–5.Google Scholar
- 5.Okamoto H, Sasaki T, Tsubomizu Y, Satake Y, Fujita R. Overlooked colonic neoplastic polyps after endoscopic polypectomy [in Japanese with English abstract]. Gastroenterol Endosc 1989;31:1241–6.Google Scholar
- 9.Kitajima N, Yamashita Y, Fujimi T,et al. A colonic polyp showing interesting endoscopic and pathologic features after endoscopic polypectomy [in Japanese with English abstract]. Endosc Dig 1994;6:1493–8.Google Scholar
- 10.Tanaka S, Haruma K, Tanimoto T,et al. Ki-67 and transforming growth factor alpha (TGF-α) expression in colorectal recurrent tumors after endoscopic resection. Advances in Gastroenterological Carcinogenesis I. Bologna: Monduzzi Editore, 1996:1079–83.Google Scholar
- 11.Nishiyama M, Takagami S, Kirihara Y,et al. The indications of chemosensitivity tests against various anti-cancer agents. Surg Today 1988;18:647–52.Google Scholar
- 33.Ito M, Yoshida K, Kyo E,et al. Expression of several growth factors and their receptor genes in human colon carcinomas. Virchows Arch B Cell Pathol 1990;59:173–8.Google Scholar
- 37.Takahashi Y, Mai M, Wilson MR, Kitadai Y, Bucana CD, Ellis LM. Site-dependent expression of vascular endothelial growth factor, angiogenesis and proliferation in human gastric carcinoma. Int J Oncol 1996;8:701–5.Google Scholar
- 48.Kajikawa K, Yasui W, Sumiyoshi H,et al. Expression of epidermal growth factor in human tissues. Virchows Arch [A] 1994;418:27–32.Google Scholar