The Prostate Cancer Foundation has expressed cautious optimism about a significant advance in the treatment of prostate cancer.
Doctors at the Royal Marsden Hospital in London say tests of a drug called abiraterone have proved it is highly effective in shrinking tumours in nearly 80% of patients.
The drug works by blocking the hormones that enable the cancer to grow. Doctors are hailing it as the most significant step in cancer research of more than 70 years.
However, the trial is in only its first phase and involved just 21 people, though Kat Arny from Cancer Research UK says a bigger trial is planned.
Dr Arny says the drug blocks production of the male sex hormone testosterone, which fuels growth of prostate cancer cells.
About 700,000 men worldwide are diagnosed with the cancer each year.
Dr Arny says it is possible the drug could also be used to treat breast cancer.
Prostate Cancer Foundation president Barry Young says the drug is for those with advanced cancer, and the present approach is to identify prostate cancer early enough to cure.
Mr Young says people should be cautious until more information is known about the drug.
Urologist and prostate cancer specialist Peter Davidson says there is a good chance the drug may come to New Zealand as a part of clinical trials.
He says larger trials will be important in giving a greater indication about the effectiveness of the drug.