The pituitary gland, highlighted here along with a tumour, is located at the base of the brain. — Photos: Wikimedia Commons
“T” is for tumour and although that often sounds scary, patients diagnosed with pituitary adenoma should know another “T” word, i.e. treatable.
Yes, this particular tumour is indeed treatable.
These abnormal, but benign, growths in the brain arise from the anterior part of the pituitary gland, which is located at the base of the brain, behind the nose and right in the middle of the head.
The pituitary is known as the “master gland”, an acknowledgement of its role in controlling other glands that release hormones, such as the thyroid and the adrenal, which then enable other organs to function properly so that your body is in working order.
Due to its multiple functions, not all pituitary adenoma patients experience the same symptoms.
Typical symptoms
For 35-year-old junior executive A. S. (who did not wish to reveal her full name), it all began with bad headaches.
“It just wouldn’t go away. I suffered for weeks,” she shares.
The mother of one had trouble conceiving as well.
A blood test detected an elevated level of hormones in her bloodstream.
As for copywriter Hu Ah-Ping, her eyesight deteriorated, which she initially assumed was due to worsening myopia (shortsightedness).
However, an optometrist found little need for her to get new glasses as her prescription had not changed much upon checking.
“As time went by, my vision became even more blurry.
“It felt like I was looking through smudged glasses.
“My left eye was especially bad; it couldn’t decipher the start of each sentence whenever I was doing any reading.
“The first few letters of every line were obscured,” she says.
Subsequently, an ophthalmologist ran a visual field test, which confirmed that her peripheral vision was poor.
The 57-year-old was told to get an MRI (magnetic resonance imaging) to find out whether there was something in her brain that was preventing her from seeing clearly.
According to consultant neurosurgeon Dr Muruga Kumar Rajoo, these cases are textbook examples of a pituitary adenoma.
He says that about one in five patients referred to him have symptoms like headaches and hormonal disturbances.
The remaining majority are patients who had suffered from vision loss.
“Patients with bitemporal hemianopia would feel like there is a curtain covering their vision from the side,” he explains.
Bitemporal hemianopia is the medical term describing a loss of vision in the outer halves of both the right and left visual field.
An MRI or CT (computed tomography) scan is usually done to confirm the presence of the tumour.
This illustration shows a normal pituitary gland and a pituitary tumour pressing on the optic nerve, which then gives rise to visual problems. (Editor’s note: American spelling is used in the illustration.)
Functioning and non-functioning
According to John Hopkins University in the United States, about one in 10 people will develop a pituitary adenoma at some point in their lives.
These adenomas can be classified as “non-functioning” or “functioning” tumours, which is determined through a blood test.
This blood test is required as the pituitary gland produces, among others, the growth hormone (for bone and tissue development) and prolactin (for lactation).
Non-functioning tumours do not produce excessive hormones, but they can press on the optic nerves, or other nearby structures, thus causing vision loss or headaches.
Dr Kumar has seen older patients with large tumours who assumed their vision loss was due to ageing.
“The pituitary adenoma is a slow-growing tumour that shows only minor symptoms at first.
“It progresses gradually without the patient realising it,” he notes.
As for functioning tumours, he says that patients may experience significant hormonal changes and imbalances.
This causes symptoms that can range from facial puffiness and weight gain to changes in the menstrual cycle of some women, thus affecting their fertility.
There are instances where it could even lead to acromegaly.
“When there is too much growth hormone, patients may develop acromegaly where the hands and legs become large.
“Their face could develop coarse features,” he says.
The late American actor Richard Kiel was said to be a striking example of someone with acromegaly, or gigantism in layman’s terms.
His most well-known role was as Jaw, the villain with steel teeth in two James Bond movies The Spy Who Loved Me and Moonraker.
The condition was believed to have contributed to his 2.18 metres (seven feet two inches) frame.
According to The Washington Post, he was already six feet seven inches by the time he reached 14.
Dr Kumar, who has dealt with pituitary adenoma cases since 1998, says that hormonal imbalances, if left untreated, could lead to serious health complications, such as high blood pressure, diabetes and heart failure, in worst case scenarios.
But in the shadow of a pituitary adenoma diagnosis, the other “T” word comes into play.
Treatment options
An example of how the visual field of a patient with bitemporal hemianopia – a common symptom of pituitary adenoma – looks like.
Certain types of pituitary adenomas can be treated with medication to shrink the functioning tumours.
“This is especially so in the case of the prolactinoma, which is very responsive to medication,” Dr Kumar says.
“If the tumour doesn’t shrink with medication, then an operation will be necessary.”
As for small non-functioning tumours that are less than one centimetre wide and not pressing on the optic nerve, he says that these cases can be treated with a single shot of focused radiation (radiosurgery) on the targeted area.
“For larger tumours that are causing vision impairment, a surgical procedure is the most effective way,” he adds.
The tumour can be removed through the nose in a minimally-invasive surgery known as transsphenoidal hypophysectomy.
This surgery typically involves both a neurosurgeon and an ear, nose and throat (ENT) doctor.
It usually takes about an hour with an endoscope camera, using a computer-guided navigational system for precision.
“The hypophysectomy is generally safe, but as with all surgical procedures, there is still a degree of risk,” says Dr Kumar.
For instance, there could be life-threatening complications such as a stroke if nearby arteries are injured or damaged during the procedure.
“In addition, if the pituitary gland is damaged, female patients may experience fertility issues in the future,” he points out.
Occasionally, there is also a possibility of brain fluid leak, which may require an endoscopic repair.
According to Dr Kumar, patients usually need to remain in the hospital for about three days after the surgery for monitoring.
Most procedures, however, are straightforward cases with fast recovery as there is no incision into the skull, he says, noting that such patients can usually resume work in less than a month.
“Sometimes, there may be a small residual [growth] left behind because it is stuck to a blood vessel.
“The surgeon would not want to risk damaging the vessel by removing it.
“This can be adequately treated with radiosurgery. “In other words, the patient does not have to go through a repeat surgery,” he says.
He adds that patients who have had symptoms like vision impairment would also regain their faculties.
However, in cases of tumours larger than 5cm, patients may require a craniotomy, where either a small hole is made in the skull or a piece of bone is removed to allow access to the tumour.
“A craniotomy to resect the tumour carries a much higher risk than going through the nostrils,” notes Dr Kumar.
He relates the case of a male patient who had a pituitary tumour that had gone unaddressed for several years.
One day, the man found that he could not move his eyes.
“We did a scan and discovered that the tumour had suddenly expanded, pressing on some cranial nerves, and had haemorrhaged [bled].”
An emergency surgery was carried out, he says, noting that the patient’s eyes took about four to six months to recover.
This condition, known as pituitary apoplexy, refers to a complication that arises from an untreated pituitary tumour that grows abruptly and starts bleeding internally.
While there is no known cause for pituitary adenomas, there are grounds for optimism in dealing with these non- cancerous tumours.
As Dr Kumar puts it: “It is a spontaneous tumour. It happens randomly.
“But if it is addressed adequately, you are cured for life.”
