IMPROVED ENDOSCOPIC RESECTION OF LARGE FLAT LESIONS USING AN EXTERNAL ADDITIONAL WORKING CHANNEL (AWC)

Aims:

En-bloc resection of lateral-spreading polyps and flat lesions larger than 2 cm in size can be challenging. EMR offers the opportunity for resection in piece-meal technique, but completeness (R0) of the resection remains unclear. In contrast, ESD is complex, time consuming and associated with a significant rate of perforation.

Methods:

A modified grasp and snare technique was developed using a new external additional working channel (AWC). The device can be fixed at the tip of a standard gastroscope or pediatric colonoscope. In the video two different approaches are demonstrated: In one case en-bloc polypectomy of a 4 cm large flat polyp in the colon near the right flexure was performed in a modified grasp and snare technique, with an anchoring device inserted through the working channel and a snare inserted via the AWC. In the other case an ESD of an early gastric cancer in the antrum at the posterior wall is shown. Here a grasping snare was introduced via the AWC to enable counter-traction by pushing away the partly incised lesion during submucosal dissection.

Results:

In both cases the endoscopic procedure was performed successfully with histologically verified en bloc resection in both cases.

Conclusions:

Based on our preliminary experience the AWC helps to reduce current limitations of EMR and ESD. Furthermore in contrast to a dual channel endoscope, attachment of the AWC to a standard endoscope enables variable positions of both working channels by turning the cap clockwise or counterclockwise before fixation to the scope.