THE pituitary gland is called the "master gland" because it controls several other hormone glands in your body. As a result, a pituitary tumour can lead to serious health problems.
The pituitary gland is a tiny gland that is located inside the skull, above the nasal cavities and beneath the brain. It is located in the sella turcica, a very small bony area. The optic nerves, the nerves that link the eyes and the brain, pass closely above it.
The hypothalamus, an important region of the brain, is directly connected to the pituitary gland.
This establishes a crucial link between the brain and the endocrine system, a group of glands that control hormones in the body. The hormones are released into the blood, which are crucial in controlling the body's organs.
The pituitary is considered the "master control gland" because it controls the number of hormones released by other glands in the endocrine system.
HOW COMMON ARE PITUITARY TUMOURS?
Pituitary adenomas make up approximately 10 per cent of all tumours that develop within your skull. It affects 77 out of every 100,000 people, although experts believe that up to 20 per cent of people will develop adenomas at some point in their lives.
Due to the fact that many pituitary adenomas, particularly microadenomas, are asymptomatic, they are frequently undetected.
The causes of pituitary tumours are unknown. Sometimes gene mutations may increase an individual's risk for developing pituitary tumours. However, there are no known lifestyle-related or environmental causes of pituitary tumours.
Most people who develop these tumours do not have a family history of the disease. But rarely, pituitary tumours can be a part of hereditary syndromes.
Depending on the type or size of the tumour, there may be deficiency, or overproduction of one or more hormones.
Functional pituitary tumours produce hormones and can cause a variety of signs and symptoms, depending on the hormones they produce.The signs and symptoms of non-functional pituitary tumours, meanwhile, are related to tumour growth and pressure on the surrounding structures.
Large pituitary tumours, those about one centimetre or larger, are called macroadenomas. Due to the size of the macroadenoma, it can put pressure on the normal pituitary gland and adjacent structures, such as the optic nerves and brain.
Commons signs and symptoms include frequent headaches, and vision loss, particularly peripheral vision. Larger tumours can cause hormonal deficiencies and symptoms which include nausea and vomiting, lethargy, feeling cold, disruption of the menstrual cycle, sexual dysfunction, frequent urination and unintended weight loss or weight gain.
TREATMENT
Depending on the type, size and location of the tumour, management options may be surgery, medication, or just regular monitoring by the surgeon.
As there are various types of pituitary tumours, there is no single best treatment. Surgery may be done via a transsphenoidal approach, a minimally invasive technique, where the surgeon removes the tumour through the nose, or transcranial, through an opening in the skull, depending on the tumour size and location.
In certain cases, Stereotactic Radiosurgery, a very precise form of therapeutic radiation may be considered.
For smaller tumours, if detected and treated early, the prognosis is very good, and most patients will recover and be able to lead a normal life. Therefore, it is important to seek consultation and get treatment early if indicated.
There is no evidence showing that stress may directly cause pituitary tumours, or other tumours in the brain for that matter.
Depending on how badly the optic nerves are affected by the tumour, some patients may have improved vision after surgery. However, one of the main aims of the surgery is to prevent the patient's vision from deteriorating further by removing the tumour compressing on the optic nerves.
Untreated, a pituitary tumour may grow large and compress on the optics nerves, eventually causing blindness.
It may also disrupt the flow of cerebrospinal fluid in the brain, causing it to accumulate in a condition called hydrocephalus. Hydrocephalus is a life-threatening condition and is treated as an emergency requiring surgery. Excessive or deficient hormones in the body may also cause physical changes in a person's appearance, while affecting blood pressure, blood sugar, menstrual cycle in females, metabolism and sexual function among other things.
If your doctor suspects that you have a pituitary tumour, she or she will take the history of your condition and conduct a physical examination with some blood investigations. This will be followed by MRI of the brain and pituitary gland.
*The writer is a consultant neurosurgeon at Gleneagles Hospital Penang.