01/03/2016 3:32 PM AEDT | Updated 15/07/2016 12:51 PM AEST

World's Greatest Shave Is More Than Just A Dare To Go Bare

In 2008, Zahne Castley noticed her husband, Barry, had what she describes as "a bit of a puffy collarbone."

"He refused to go to the doctor because he didn’t believe there was anything wrong," Castley told The Huffington Post Australia. "It wasn't extreme or anything -- it just looked a bit weird, a bit puffy, and different to the collarbone on the other side.

"He is just such an easy going bloke, I had to put my foot down a bit."

It's lucky she did, as it turned out that puffiness was a sign of Hodgkin Lymphoma -- in other words, cancer of the lymphatic system.

The diagnosis was delivered to the couple on their wedding anniversary.

"Because we live remotely [in Mount Isa] we received the news by phone, as we couldn't get in front of a doctor," Castley said. "I could tell by the look on his face what the news was.

"It snowballed from there very quickly. We had two weeks to pack and get out of Mount Isa so he could get the treatment he needed."

The Castleys, whose son Jaxon was at that stage nine months old, had to relocate almost immediately to Townsville, 900km from home.

The Castley family today.

It is a decision Zahne Castley says was made much easier with the assistance of The Leukemia Foundation, which helped her and Barry find accommodation in Townsville for the seven months they would need to live there.

"Firstly they found us temporary accommodation at a motel, and then when a unit became available at the Freemasons Village (adjacent to the Townsville Hospital) we all just stayed there. Barry was even able to live in the village with us, except a couple of times when he had to be admitted.

"If it weren't for [the foundation], this all would have been extremely challenging financially. At that time I was a stay at home mum and Barry was providing our family income. If we had to have moved and not had accommodation, it would have been extremely difficult financially and just added so much stress to what was already a stressful situation.

"We were just very fortunate in that it was just seamless. We didn’t have to do very much."

For these reasons, the now mother-of-two has no qualms about picking up the razor and shaving her head as part of the charity's annual fundraising event, the World's Biggest Shave, taking place from Thursday March 10 to Sunday March 13, 2016.

"I have actually wanted to take part since Barry’s cancer, just because I felt like I wanted to repay what was given so freely to us," Castley said.

"But up until this year my children have been very little, and I felt they wouldn’t understand why I looked so different. In saying that, they are not happy about it now, but they understand why I'm doing it."

Formed in 1998, the World's Greatest Shave now boasts 150,000 participants each March who are sponsored to either shave or colour their hair in order to support Australians with blood cancer and fund research.

"It’s a busy time. There are a lot of people signing up to shave their heads in the next couple of weeks," Head of Fundraising at the Leukaemia Foundation, David Simms, told HuffPost Australia.

"It’s a big thing, shaving your head, but here we are with over 100,000 people across the country making that extraordinary decision and getting people to sponsor them to do it."

This year, Simms says the charity aims to raise $18 million.

"That’s about half the money The Leukemia Foundation needs each year to support families going through all the different blood cancers, as well as research into better treatments," Simms said.

"It can be a very long journey when you get a blood cancer. It can be long and grueling. A lot of research we fund is looking at better ways to treat patients.

"We all hope and dream of a cure, but that’s a long way off. In saying that, we have made huge strides in recent years, coming up with drugs that help people deal with their cancer. There are many drugs now which as recently as seven years ago were not available."

Interested in becoming involved? You can sign up here or, if you want to make a donation to The Leukemia Foundation, you can do so here.