The mad dash that is the Golden Slipper is the biggest race of trainer Rick Worthington's professional life.

It comes as he continues the marathon battle in his personal life.

Two days out from saddling up Honesty Prevails in the $3.5 million race, Worthington has to travel from Warwick Farm to Sydney's North Shore to undergo treatment for the cancer that has turned his life upside down.

Worthington was diagnosed with stage three melanoma in 2012 and struggled to keep his stable going as he also dealt with the break-up of his marriage.

His post-surgery treatment involves the infusion of a drug being used in a clinical trial.

So far, so good.

"I'm having my 40th treatment this week," Worthington said.

"It is an infusion with a trial drug and hopefully my tests this week are good."

Before his cancer diagnosis, Worthington had some talented horses in his stable headed by Group Two winner Whitefriars.

He is also known as a respected horse breaker and pre-trainer.

"My stable was decimated four or five years ago during the cancer," he said.

"We've built it back up but have had very few runners and most of those in the bush.

"So to have this filly with a Group win already and to get her in the Slipper, it's something I didn't think would happen."

The winner of the Widden Stakes on debut in January, Honesty Prevails is not considered a leading contender after her fourth in the Reisling Stakes won by French Fern.

"She was on the slowest part of the track that day but it was still disappointing," Worthington said.

"But (jockey) Jason Collett came and galloped her on the course proper at Warwick Farm on Tuesday.

"It was a very nice piece of work so we're happy she is back."

While others steered away from Worthington's stable, Trevor Gluck had no hesitation contacting Worthington to help him find a horse at the Magic Millions sale.

The filly which would become Honesty Prevails tested the purse strings when they had to go to $720,000.

"I'm just so pleased Trevor and the other owners gave her to me to train," Worthington said.

"She was an expensive filly and she has a wonderful pedigree page but mostly she is an athlete. That's what attracted us to her."

The trainer believes she deserves her place in the Slipper field but is also looking ahead.

"She will be better when she gets up over further than 1200 metres," he said.

While Worthington is invested in the filly's future, Honesty Prevails will play a big part in his own.