A rare and deadly form of melanoma in the eye can now be detected through a simple blood test rather than a costly, invasive biopsy into the eyeball after which people have to wait for weeks for their results.

Uveal cancer is a particularly lethal from of the disease. In about half of all cases, the tumour will spread to other parts of a patient's body.

Every year about 250 Australians are diagnosed with the cancer, which previously involved an agonising wait as samples were sent to the UK for testing.

One man who understands what this breakthrough means is Peter Samson, who first realised something was wrong when his vision collapsed in 2015.

"I was sitting at the computer doing some work and all of a sudden I couldn't actually focus on the words, it was like a curtain came over my eyes," he said.

Mr Samson initially called his optometrist thinking it was a detached retina, but was immediately alerted to the seriousness of the situation.

"We did tests and he was very concerned there was something there and within hours they had a big picture on the screen," he said.

"I was told to have an ultrasound on my liver to check that it hadn't spread."

Mr Samson had a biopsy while getting surgery for the melanoma, and had to wait for more than a month while the sample was sent to the UK for testing.

He was one of the lucky ones, but the wait for the results was excruciating.

"That was a really horrible time, not knowing what you are dealing with … I think I tried to keep it out of my mind. I am an optimist … I was hoping for the best," he said.

Chromosomes key to prognosis
Researchers from Western Australia's Edith Cowan University have developed a simple blood test which can now determine if the cancer is at risk of metastasising to the liver.

Aaron Beasley was part of the research team which mapped the genetics of the cancerous cells to detect if they were present in a patient's bloodstream.

"In cancer cells, sometimes they have dysregulation of the cells and they can gain or lose chromosomes. So what you are looking at is the amount of chromosomes that are in the cell, and that can tell you a patient's prognosis," he said.

Mr Beasley said the trial meant patients could begin treatment sooner, and those patients who were diagnosed with uveal cancer could be diverted into clinical trials.

Breakthrough 'crucial' for patient outcomes
The discovery also brings several other benefits according to co-lead researcher Elin Gray.

"It's less invasive so you don't have to do it through a biopsy to the eye, which can create complications … especially if you have the benign type, you don't want to compromise the vision," Dr Gray said.

"It's a big breakthrough to be able to do it rapidly, less invasive so we don't have to potentially compromise the eye and then the results are expedited.

"It's crucial for better outcomes … even if they have the aggressive form they will be monitored more closely…"

Mr Beasley said the test would also help doctors have a much clearer picture about the cancer's progression.

Researchers are already looking to expand the trial through collaborations with universities around Australia and the United States.