Lealiifano is in remission after two rounds of chemotherapy treatment and will have a bone-marrow transplant in Melbourne in November after being matched with his younger sister.

He faces a 12-month recovery after being diagnosed with leukaemia in August and says he has been overwhelmed by the support of rugby players around the world and fans.

The Brumbies will offer Lealiifano a coaching position if he is unable to play in the 2017 Super Rugby season to keep him involved at the club.

But Lealiifano hopes he will be well enough to take his place on the field in the future.

"I think I'm a long shot of playing next year, maybe 30 per cent chance if I had to say but it's hard," Lealiifano said.

"I don't want to get my hopes up because it would be hard to take if I don't get there, so I'd rather stay realistic and level-headed.

"But at the same time I like to dream big and think I could play next season. I've spoken to [Brumbies coach Stephen Larkham] about it at length and the processes I could go through.

"But he's just worried about me getting my health sorted. If I'm a chance to play at the back end of next year, that's an extra bonus and would be an absolute blessing.

"If not, I'll be able to move on and continue trying to get better. That's the realistic goal, this thing could take a few years.

"Initially everyone thinks you'll go through chemo and be sweet. But the process is quite an intricate one with so many risks."

Lealiifano will join Brumbies and Canberra Vikings players in the Leukaemia Foundations' "Light the Night" walk on the Kingston Foreshore on Friday night to raise money and awareness for those with blood cancer.

Lealiifano was diagnosed with leukaemia after feeling run down and "not myself" at training in July and August.

At first it was thought he was tired because of a long rugby season and the birth of his first child Jeremih✓.

But tests discovered leukaemia and Lealiifano was immediately put in hospital to begin treatment just a month after Jeremih was born.

"I didn't have much time to sit down and really register it all," he said.

"It was a massive shock to myself and the whole family. But as soon as I found out it was about tackling it head on and finding the next process to get better."

Having been through two treatments of chemotherapy, the next stage will be a bone-marrow transplant with his younger sister in Melbourne.

"Each day is going to be a battle ... to have a long term goal to see the light at the end of the tunnell is nice but it's day by day," Lealiifano said.

"I've had two treatments of chemotherapy which have pretty much put me in remission going into this transplant so hopefully the transplant goes well and gives me every chance of beating this leukaemia.

"Both bouts I got infections on both because you've got no immune system ... it's all part of the journey. Up and down days and it definitely knocks you about, but I'm staying positive.

"They test the best matches [for bone marrow transplant] and the best chance is your siblings and if you don't get any luck there you go on a world register.

"But luckily enough for me my younger sister is a match. For the family that is quite a special thing and for your sister to give you the gift of trying to save your life, it's quite special.

"I'm reasonably positive. The things in my favour are that I'm young, pretty fit and I've got a suitable match. One thing they can't guarantee is that everyone will be cured, but it gives you every chance of beating it."

Lealiifano thanked the Brumbies and their fans for rallying around him at his darkest moments.

"We talk about family and that's what makes this place special. This rugby community and the Brumbies have been really, really special with helping in any way they can," Lealiifano said.

"[Light the Night] is an amazing initiative. Everyone knows someone who has gone through it and to head out there tonight ... it's really, really humbling to see that support for not only myself but others in the community going through similar things."