One focal ablation assembly (72), used with an endoscope (12) comprising an endoscopic tube (16), comprises a cryogenic catheter (26), a balloon (74) and a reinforcing element (88). The cryogenic catheter is placeable within the endoscopic tube channel (28) and has a distal end (34) placeable at the distal end (24) of the endoscopic tube. The balloon is mountable to the catheter distal end (34) and extends distally of both of the distal ends. The reinforcing element at least partially defines the shape of the balloon in the expanded state. The balloon has a thermally conductive therapeutic region (36) which provides effectively no thermal insulation. Another focal ablation assembly (14) uses a cap (22) instead of the balloon. The cap substantially maintains its shape during use while not causing tissue trauma.
