We study the epitaxial overgrowth of GaAs over mum-sized W-patterns by metalorganic vapor-phase epitaxy (MOVPE). Rings and circles of W have been overgrown under various growth conditions and the lateral overgrowth has been characterized by inspecting the surface. The main results of this work are the identification of the most prominent surfaces in the growth front, an increase of the orientation-dependent lateral overgrowth with decreased temperature and the controlled formation of nm-sized openings extending down to embedded metallic elements. The control of these issues is necessary for fabrication of devices which contain embedded metallic features.