Therapeutic procedures for submucosal tumors in the gastrointestinal tract

Table 1 Various endoscopic therapeutic procedures for the treatment of SMTs

	Indication	Contraindications1	Complications	Advantages	Disadvantages
SSP[1,56]	SMT < 2 cm; polypoid/pedunculated; sessile with a base < 1-2 cm; intraluminal and originating in muscularis mucosa or submucosa	SMT > 2 cm; originating from the muscularis propria; intramural SMT; extraluminal SMT; located on the lesser curvature, posterior aspect of the stomach body or the cardia	Incomplete resection, hemorrhage, perforation (when the SMT is > 2.5 cm)	High success rate, few complications	See "Complications"
SB[1,9,10,57,58]	Same as for SSP	Same as for SSP	Minor bleeding treated with saline inj., metal clips or liquid thrombin	The saline injection prevents full-thickness burning and perforation; high success rate; safe, quick and easy method	If the saline is injected in the surrounding tissue, the SMT will become sessile and therefore more difficult to remove
ESMR-L[1]	SMT < 1 cm	SMT > 1 cm; originating from the muscularis propria	No serious complications have been reported	Not restricted by the location of the SMT; achieves deeper resection than SB and conventional EMR and thus a higher rate of curative resection	This technique can only be applied to small SMTs
ESMR-C[1]	SMT < 2 cm	SMT > 2 cm; SMTs in the muscularis propria	Minor hemorrhage, though rare.	Simpler and easier version of EMR; high success rate; saline inj., see SB	See "Complications"
UT[1,58]	Simple and multicystic SMTs (e.g. lipomas and cystic lymphangiomas)	Vascular tumors	Hemorrhage	Reduced risk of perforation, due to the fact that only the upper half is removed; can be applied to larger tumors	Only applicable in cases of lipomas and cystic lymphangiomas
EE-M[1]	Easiest if well capsulated; large SMTs and SMTs in the muscularis propria can be removed by this technique	SMTs with wide bases, severe adhesions or not well capsulated	Minor hemorrhage	Can be used to resect leiomyomas originating from the muscularis propria; sessile or large SMTs > 2 cm can be resected	Very difficult to perform
EE-I[1]	Large SMTs and SMTs in the muscularis propria can be removed by this technique	Unknown since this is a new technique	Perforation, minor hemorrhage	Like EE-M this technique is not limited by the size, sessile form or association with the muscularis propria	New method, which means that the efficacy and safety is not known for sure

¹These are not absolute contraindications, but should rather be seen as circumstances, where resection is complicated. SSP: standard snare polypectomy; SB: strip biopsy; ESMR-L: resection performed with a ligation device; ESMR-C: endoscopic submucosal tumor resection with a transparent cap; UT: unroofing technique; EE-M: endoscopic enucleation performed with an initial mucosectomy; EE-I: endoscopic enucleation performed with an insulated-tip electrosurgical knife.