Methods treat a tissue region. In one arrangement, the methods deploy an electrode on a support structure in a tissue region at or near the cardia of the stomach. In one embodiment, the support structure has a proximal region and a distal region. The proximal region is enlarged in comparison to the distal region, and the electrode is carried by the enlarged proximal surface. The methods advance the electrode in a path to penetrate the tissue region and couple the electrode to a source of radio frequency energy to ohmically heat tissue and create a lesion in the tissue region.