If a pituitary tumour is present, treatment must be directed at arresting and reversing tumour growth. Surgical decompression is usually required to relieve pressure effects on parapituitary structures (such as the optic chiasm or contents of the cavernous sinus) when the lesion cannot be shrunk medically (for example, a prolactinoma). This is the case with functionless tumours when after surgery, radiotherapy may be used to prevent regrowth of the tumour.
