A device for accessing a hollow organ comprises an elongated body sized for insertion into an entrance passage to the hollow organ, the elongated body including an outer sealing surface engaging an inner surface of the entrance passage and a working channel extending therethrough from a proximal port which, when the elongated body is in the operative position is proximal to a proximal opening of the entrance passage, to a distal port which, when the elongated body is in the operative position, extends distally past a distal opening of the entrance passage into the hollow organ and a plurality of suction holes formed through an outer wall of the elongated body, disposed around a circumference of a portion of the elongated body which, when the elongated body is in the operative position, is located within the entrance passage in combination with a vacuum channel formed in the elongated body for transferring a negative pressure to the suction holes to increase a sealing force applied by tissue of the entrance passage to the outer surface of the elongated body.