Given the task definition and input, reply with output. In this task, you will be given sentences in which your task is to recognize the name of the organ of the body. An organ is a collection of tissues that structurally form a functional unit specialized to perform a particular function. Although there might be several correct answers, you need to write one of them.

 Over 90 % of the surviving patients had solitary , small and low - stage invasive tumors completely resected and 83 % survived without relapses in the bladder . [ 1 ]
bladder