Abstract: Several embodiments of an endourethral prosthesis, assembly, and attendant methods are provided for patients presenting with lower urinary tract symptoms (LUTS) or urinary retention. The endourethral prosthesis includes a reversibly expandable element disposed circumferentially about, and longitudinally along a tubular member adapted to receive urine. The tubular member is positionable within a lower urinary tract such that the reversibly expandable element operatively engages a structure of the lower urinary tract so as to prevent migration of the prosthesis so positioned. The reversibly expandible element is in non-reversible fluid communication with the tubular element for selective expansion thereof, the reversibly expandible element is further operatively engagable so as to discharge fluid non-reversibly received from the tubular member exterior to same.