• The test is useful along with other tests for the screening of pituitary tumors. It should however, not be used in isolation for the diagnosis of pituitary tumours.
• For monitoring treatment and relapse in patients with pituitary and hormone dependent tumours.
• The test may be used as a prognostic marker for survival following certain brain surgeries.
•  To know the stage of cancer as well as the metastasis status
• The test can help detect recurrence, metastasis and residual cancer: This may even include patients with a history of cancer of other organs like breast, lung, pancreas etc.

Depending on the size of the tumour, brain or pituitary tumors may produce the following signs and symptoms:

• Headache [radiating or non-radiating]
• Pain, numbness or facial muscle weakness [due to facial nerve impingement]
• Pain radiating to ears
• Nausea, vomiting
• Seizures
• Visual disturbances with drooping eyelids

It is also recommended to get tested in the following cases:

• Hormonal abnormalities with unexplained weight loss
• Menstrual irregularities
• Behavioural or physiological changes
• Family or past history of cancers
• Recent surgery of the brain or pituitary gland.

This test requires a blood sample. A tourniquet (elastic) band is placed tightly on the upper arm. The patient is then asked to make a fist. This helps in the build-up of blood filling the veins. The skin is disinfected before needle insertion and the blood sample is collected in vacutainer.