Instead, she was adjusting to life as vision impaired after having a tumour removed from her brain.

The NSW Hunter region woman, now 23, had been experiencing strange symptoms including lactation and not menstruating, so went to see a gynaecologist who sent her for an MRI.

"They found it straight away," Ellie said.

"It was benign, but they had to operate on it one month after they found it. It was wrapped around my optic nerves, and I lost a lot of eyesight after the surgery, which hasn't come back, so it's left me partially blind."

The experience was "a massive shock to the system" for Ellie - one that uprooted her entire life and had long lasting impacts.

She was halfway through her first year of studying nursing at university, something she committed her high school study towards, but had to drop out of the degree as a result of the impairment the surgery caused.

"I didn't have enough eyesight to continue," she said. "So it was it was a big, big change to my life. It changed my career path. I now do bookkeeping and I have no issues there because you can up the size of things on computers.

"I'm 23 now and I feel like I've only just started to feel confident in myself again, but just adjusting to the eyesight, it was very difficult.

"Especially being so young when all my friends were going out partying, and I was just at home. I didn't have the confidence to go out."

The thought of cancer also wasn't something the teenager had not imagined happening to her.

"No one around me had it," she said. "You just didn't hear about it.

"You're 18. You haven't even started living yet. I just had no idea. I had no understanding on everything that was going on."

To help her understand some of what she was going through, Ellie credits the Mark Hughes Foundation, which came into her life while she was still in hospital after the surgery.

"They just approached and introduced themselves," Ellie said.

"They gave me a beanie and they've been supporting me ever since that surgery. They book in my regular MRIs to check up on the tumour, because they didn't actually get all the tumour. There's still half of it left."

The Mark Hughes Foundation also mentioned the Big 3 Trek to Ellie - a 150km walk from Sydney to Newcastle three locals organised last year to raise money for the brain cancer charity, and are holding again this month.

It was something Ellie jumped at right away.

"It's to prove to myself that I don't need someone by my side to be able to do a challenging thing," she said. "And I also really wanted to just give back to the Mark Hughes Foundation - because they're so amazing."

IN OTHER NEWS:

One of the organisers of the trek, Luke Alexander said it was inspiring to have someone like Ellie put their hand up to take part. The group of participants has also grown from 25 people last year to almost 50 this time.

"We've got 17 new people this year, so we'll look after them." he said. "It's amazing how many messages we've had from people asking to join, but the logistics just made it too hard to take everyone."

The event launches on June 28, with media personalities, sports stars, celebrities and brain cancer survivors walking five kilometres from NRL HQ to the Sydney Opera House. The trek officially gets underway on June 29, and participants will arrive in Newcastle on July 1 for the NRL Knights v Titans game during Beanies for Brain Cancer round.

Luke said those who did it last year were shocked at how difficult the feat was, but knowing why they were doing it spurred them along.

"It's sad how many people are affected by this," he said.

The fundraiser has already amassed about $50,000 for the Mark Hughes Foundation, after $106,000 was raised for the charity last year. The group also did a trek in the opposite direction in January to support the McGrath Foundation and its efforts to fight breast cancer.

To support the cause, visit challenge.markhughesfoundation.com.au/page/TheBigThreeTrek

The Mark Hughes Foundation's beanies for brain cancer will also go on sale on Wednesday. They're available on the MHF website or in-store at IGA and Lowes.