THERAPEUTIC STRATEGY FOR COLORECTAL LATERALLY SPREADING TUMOR
Article first published online: 22 JUN 2009
© 2009 The Authors. © 2009 Japan Gastroenterological Endoscopy Society
Special Issue: Proceedings of the Endoscopy Forum, Japan 2007–2008
Volume 21, Issue Supplement s1, pages S43–S46, July 2009
How to Cite
Oka, S., Tanaka, S., Kanao, H., Oba, S. and Chayama, K. (2009), THERAPEUTIC STRATEGY FOR COLORECTAL LATERALLY SPREADING TUMOR. Digestive Endoscopy, 21: S43–S46. doi: 10.1111/j.1443-1661.2009.00869.x
- Issue published online: 22 JUN 2009
- Article first published online: 22 JUN 2009
- Received 22 January 2009; accepted 13 February 2009.
- endoscopic piecemeal mucosal resection;
- endoscopic submucosal dissection;
- laterally spreading tumor (LST)
Most colorectal tumors larger than 20 mm in diameter are called laterally spreading tumors (LST), most of which are adenomatous lesions. Laterally spreading tumors are classified into two types according to their morphology, granular type (LST-G) and non-granular type (LST-NG). Each type has two subtypes. The former consists of a ‘homogenous type’ and a ‘nodular mixed type’, while the latter consists of a ‘flat elevated (FE) type’ and a ‘psedodepressed (PD) type’. In LST-G and LST-NG FE types, type V pit pattern with magnification enables the recognition of the carcinomatous or submucosal invasive area. Most of these adenomatous large lesions can be cured by scheduled endoscopic piecemeal mucosal resection (EPMR). However, LST-G with large whole nodular type or type V pit pattern, which cannot be resected en bloc with a snare, is an indication for endoscopic submucosal dissection (ESD). The LST-NG PD has a high frequency of submucosal invasion and the submucosal invasive area cannot be recognized correctly in the pseudodepression with magnification prior to endoscopic treatment. Therefore, en bloc resection with ESD should be applied to LST-NG PD. The therapeutic strategy for choosing between EPMR and ESD for large LST lesions should therefore be determined based on the macroscopic findings of their subtype and pit pattern findings.