Even when the Albion Park Rail resident began to suffer excruciating migraines - to the point where she'd temporarily lose vision in one eye - she still thought it too unlikely that she could have a tumour.

"My best friend Emma (Logan) was diagnosed in 2013, a year after we finished high school," Teisha said. "She was so determined to beat it, and was extremely brave and strong, but she died just over two years later.

"My friend Nikki (Pike) was a massive strength for me at that time, so when she was diagnosed with brain cancer last year I couldn't believe it. When I started getting migraines this year, I thought 'there's just no way that anything could be going on in my head'."

The migraines became so severe that the 25-year-old eventually had to seek medical attention, and an MRI uncovered a 2cm by 3cm tumour in May.

"The tumour was in my third ventricle and due to the size of it, it was blocking my brain fluid flowing through the brain and down the spine, causing a pressure build-up," she said.

"Having supported two of my closest friends with their brain cancer battles over six years, it just broke me. One of the hardest things was having to tell Emma's family."

This Sunday, Teisha will join with Nikki and Emma's sister, Sarah Stace, to honour Emma - and others battling the disease - at Wollongong's Walk 4 Brain Cancer.

The walk at Beaton Park's athletics track will raise funds for the Cure Brain Cancer Foundation - which aims to increase the five-year survival rate from 20 per cent to 50 per cent by 2023.

For Teisha and Nikki, the prognosis is good. Surgeons were able to remove 90 per cent of Teisha's tumour - and all of Nikki's. Neither needed any additional treatment, although both will be closely monitored.

"I feel like I'm one of the lucky ones," Teisha said. "But there's little discussion about brain cancer - and limited funding - so I wanted to do something to raise awareness and money for research.

"I also walk in the memory of my best friend."

It's a hard day for Emma's sister, Sarah, and her parents, yet they also want to do their bit to help out.

"Nothing's going to fix things for us," she said. "But we feel a sense of responsibility to do all we can to make sure others don't end up in this position.

"That no-one else has to sit down at the doctor and hear that nothing can be done; that someone they love probably won't live past five years."

Sarah said she'd never get over the horror of hearing that her sister had inoperable, stage four, glioblastoma.

"She had as much chemotherapy as she could tolerate, as much radiation as was possible, but because of where the tumour was it was too dangerous to operate," she said. "She died a month after her 21^st birthday."

Sarah said hearing of Nikki, and then Teisha's diagnosis had been hard.

"I couldn't believe that these three beautiful people, who were all connected, had to deal with this," she said.

Nikki said having each other for support has helped all three women.

"We'll walk on Sunday to remember those who have lost their battles, and also to offer some hope to those who may be battling them now, because it is possible to come out the other side," she said.

It's the fifth annual Wollongong walk, and the event has raised more than $175,000 since 2015.

Organiser Kate Mitrovski started the walk in memory of her father Stojan who died over 25 years ago, aged 35, after a year-long battle with brain cancer.

"I was devastated to find that not much had changed in the field of brain cancer, in terms of survival rates, since my dad died," she said.

"So I started the walk to help the Cure Brain Cancer Foundation with its mission to improve survival rates."

Register online at walk4braincancer.com.au/walks/wollongong/ or from 9am on the day, with the walk (2-5km) starting at 10am.