Demi was 20 when her doctor told her she had a brain tumour the size of a grape.

When Demi* learned she had a brain tumour the size of a grape, she was a 20-year-old uni student with a casual job, a great group of friends and a loving boyfriend.

For four years, she’d been experiencing persistent migraines that became debilitating during particularly stressful periods. And if it weren’t for her insistence on being tested for a possible cause, she might not have been diagnosed until much later.

Demi found herself making continuous appointments to see her GP after struggling through the pain throughout the end of high school. Eventually, she was put on preventative medication for her migraines.

When they persisted, she pushed her doctor to refer her to a specialist. She saw a neurologist and had all of her neurons checked, along with her speech and strength — everything was fine. Demi was told her migraines were “hereditary” and not to worry. She tried to believe there was nothing else to it.

Her concern resurfaced when she was on holiday in Bali with her family. She should have been relaxed — all there was to do was sip cocktails by the pool with her sisters — but the migraines continued.

Demi insisted on having an MRI scan, and it saved her life. (Image: iStock)

So upon arrival back in Melbourne, she begged her GP for an MRI, just to get some peace of mind. Soon afterwards she got the call.

“Bring in your mum or your friend,” they said, and so she did. That's when Demi finally learned why she was in constant pain.

“All I found out was I have a brain tumour, it’s in my frontal lobe, it’s the size of a grape. And that was it,” the paramedics student told Mamamia.

According to the Cancer Council, primary malignant tumours of the central nervous system are rare. In 2007, for instance, only seven people out of every 100,000 in Australia were diagnosed with primary malignant brain tumour.

Demi was shocked to learn she was one of them. She was young and she was healthy; average, even.

“I just never would have imagined that it could happen to me. I keep myself so healthy, I eat well, I’ve never smoked a cigarette, and I’ve never done drugs. I’m so cautious with my body, I do everything right,” she said.

“It was the scariest week of my life. I could not stop crying."

Watch: The signs of ovarian cancer that every woman should know. (Post continues after video.)

She couldn't help thinking her dream in life — to have children with her boyfriend of four years — was in jeopardy. “I said to my mum when we were driving home, ‘I’m never going to get married'," Demi recalls.

She was referred to a top neurosurgeon who told her she had an Oligodendroglioma, a form of tumour that can cause changes in mood, fatigue, seizures and migraines.

A week later, she was in surgery having her brain cut into. She described the experience as daunting and surreal, adding, “it was really painful. Lying down and feeling staples in your head is horrible."

Usually a surgeon will remove a small amount of healthy cells around a tumour to ensure the whole mass is removed. With brain tumours, however, this is not possible; if healthy tissue from the brain is taken it can cause more problems for the patient post-surgery.

Demi still has a small portion of the tumour in her brain and will continue to have it checked for growth every six months. "I’m such a 'check off the list' sort of person, so knowing that I will never be able to get rid of this eats away at me," she said.

Demi had a feeling her persistent migraines weren't simply hereditary. (Image: iStock)

It's been three months since her operation and Demi is back at university, driving, going to 21st birthday parties, spending time with all of the people who supported her during her surgery. Her dream of getting married and having children is again possible.

Demi said the form of tumour she was diagnosed with can go undiagnosed for a long period of time; in fact, she was told most people don't find it until they are 30 to 35 years old.

In that sense, she was 'lucky'. But it wasn’t all luck — it was Demi's insistence on being tested that saved her life.

“If you think there’s something wrong, go see a doctor and push for tests. If I hadn’t have said I needed an MRI, I would still have this brain tumour and not know about it," she said.

Early detection is seen as the key to beating most illnesses, but with a disease like cancer, 80 per cent of patients are not diagnosed until the late stages of their disease. At this point their chances of living for another five years are less than three in 10.

We might put off having pap smears, for instance, but according to the Cancer Council 93 per cent of cervical cancer patients who are diagnosed early will be alive in five years. The test is uncomfortable, sure, but those few minutes of awkwardness could save your life. (Post continues after gallery)

Similarly, whipping your bra off in the doctor’s surgery for a checkup might feel awkward, but when breast cancer is caught and treated at Stage 1, an early and localised stage, the five-year survival rates are about 98 per cent, according to the National Breast Cancer Foundation.

The first thing Demi did when she found out about her tumour was to have another pap smear, a breast examination and a skin check. 'Why not?' she reasoned.

“The best thing is early detection. I don’t think I can stress that enough. As bad as my situation is, it’s so lucky that I found out so early, because I’m on top of it now,” she told Mamamia.

“What if you find out that there’s something wrong and you could have found it earlier? You’re going to regret it."

Have you ever been in a similar situation?

Image: iStock.

*Surname omitted by request.