A tissue treatment device comprises an elongate member including a lumen extending therethrough and an
inflatable member mounted to the
distal portion of the elongated member and surrounding an opening of the lumen, an outer surface of the
inflatable member including a conductive region having a first degree of energy
conductivity and a non-conductive region having a second degree of energy
conductivity lower than the first degree of energy
conductivity and an
energy source supplying energy to the
inflatable member to transfer energy from the conductive region to
target tissue. A method of ablating tissue comprises lifting the target
mucosal tissue from underlying tissue and inserting a distal end of an
endoscope to a desired position relative to the target
mucosal tissue in combination with inserting an elongated member including an inflatable member mounted thereto through the
endoscope to the desired position, the inflatable member including a conductive region having a first degree of energy conductivity and a non-conductive region having a second degree of energy conductivity, the second degree of energy conductivity being lower than the first degree of energy conductivity, inflating the inflatable member to place the conductive region in contact with the target
mucosal tissue and supplying energy to the inflatable member to transfer energy from the conductive region to the target mucosal tissue.