Penile implants may work if the patient has had erectile dysfunction for about one year following cancer treatment and nonsurgical therapy has either failed or is unacceptable. An implant, or prosthesis, is an effective form of therapy in many men, but it does require an operation to place the implant into the penis. Surgery can cause problems, such as mechanical failure or infection, which may require removal of the prosthesis and re-operation. However, most men and their partners are very satisfied with these devices.