Transanal endoscopic microsurgery.

Transanal endoscopic microsurgery has become an established method of transanally excising rectal tumors. It uses a closed, airtight system that provides constant rectal distension, improved visibility, and longer reach than conventional instrumentation. Virtually any rectal adenoma and properly selected cancers can be removed with this technique. Transanal endoscopic microsurgery excision of cancers requires that strict selection criteria be satisfied and is best suited for T1 cancers. Transanal endoscopic microsurgery should not replace low anterior resection or abdominoperineal resection for those cancers that have either deep penetration into the rectal wall or lymph node metastases. This procedure is safe, is associated with minimal complications, and most patients can be treated on an outpatient basis. Complications include bleeding, urinary retention, temporary soilage, and inadvertent entry into the peritoneal cavity. Once transanal endoscopic microsurgery has been mastered, it may become the technique of choice for locally excising rectal neoplasms.