A device for cryotherapy treatment of gastrointestinal lesions includes a cooling member that may be attached to a first tube for pressurizing cryogenic fluid through the tube and into the cooling member through nozzles located at the distal end of the first tube. A second tube may be attached to the cooling member for evacuating the cryogenic fluid from within the cooling member, following the fluid's expansion once it exits the first tube. The cryotherapy device may be attached to an endoscope such that the first tube may be passed through the endoscope's working channel, while the second tube may be passed along the endoscope's circumference. The cryotherapy device may further comprise securing means attached to the first tube, for securing the first tube to the endoscope's working channel, thus preventing free rotation of the cryotherapy device within the endoscope, relative to the rotation of the endoscope. In addition, the securing means assist in maintaining a constant and known location of the nozzles relative to the distal end of the endo scope.