Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) Prolactinoma, familial ?
    ### Response:
    A prolactinoma is a tumor of the pituitary gland, which controls production of many hormones.  A prolactinoma causes increased levels of the hormone prolactin.  The symptoms of prolactinoma may include unusual milk production (galactorrhea) or no menstrual cycles (amenorrhea) in women or decreased sex drive in men.
    