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.
Q:  In contrast , the 3 cases of metastatic cancer of the GB had no blood flow signal in the wall of the GB .
A: 
GB