Men diagnosed with low-risk prostate cancer may miss out on being cured of the disease because they are not monitoring their condition closely.

Almost three-quarters of Australian men diagnosed with "low risk" prostate cancer are not being actively monitored to detect disease spread, a study has found.

A decade ago there was a greater tendency to treat men with low-risk prostate cancer with surgery or radiation.

Nowadays the data suggests about 50 per cent are put on active surveillance.

The objectives of active surveillance is to avoid unnecessary treatment, but patients must undergo regular testing of prostate-specific antigen (PSA) levels.

PSA is a protein produced by both cancerous and non-cancerous tissue in the prostate; high levels can indicate the disease has spread.

A biopsy should also be undertaken within 12 months of diagnosis.

With the practice of active surveillance increasing, researchers analysed patient adherence among a group of men diagnosed with prostate cancer between August 2008 and December 2014.

The study, published in the Medical Journal of Australia on Monday, found of the 1635 participants, just 433 (26.5 per cent) adhered to the active surveillance protocol of at least three PSA tests and at least one biopsy within the first two years of diagnosis.

"Active surveillance was not implemented according to published protocols in 73.5 per cent of men diagnosed with low risk prostate cancer in this Victorian cohort study," the authors wrote.

They warn men risk dying of the disease if they are not monitored appropriately.

"If they are not being followed appropriately according to active surveillance protocols, men may miss the opportunity to be treated with curative intent," they wrote.