Friday, 27 October, 2000, 23:23 GMT 00:23 UK

PC SPES is made up of eight Chinese herbs

A herbal remedy has been shown to provide real benefit to men suffering from prostate cancer.

Researchers from the University of California in San Francisco tested the impact of the Chinese preparation known as Pc-spes.

Pc-spes consists of extracts from eight different Chinese herbs and is sold in health food stores. Pc stands for prostate cancer, while spes is Latin for "hope".

The scientists found that the preparation significantly lowered levels of a protein in the blood - prostate specific antigen (PSA) - that is closely linked to prostate cancer.

There are two forms of prostate cancer.

The hormone-dependent form is linked to the male sex hormone testosterone and improves when levels of the hormone are reduced.

The hormone-independent form continues to progress even when testosterone levels are low.

The study evaluated 70 men with advanced forms of both types of the disease.

PSA levels in all the hormone-dependent men declined by more than 80% as a result of taking the supplement.

About 97% of these patients also showed steep reductions in testosterone levels.

Mimicking oestrogen

This led the researchers to speculate that Pc-spes works like a form of hormone therapy, mimicking the female hormone oestrogen.

In men with hormone independent disease, about half had PSE declines greater than 50%.

Dr Eric Small, who led the study, said the results suggested that the supplement may offer another line of defence when standard hormone therapy failed.

"In this group of patients we can use another hormone, but beyond that, short of chemotherapy, there is not much more we can do.

"Pc-spes can be used as a second or third line hormone. We don't know what kind of impact it will have on survival, but it clearly offers a clinical benefit.

"It provides us with another treatment we can use before chemotherapy."

Some of those taking part in the study saw shrinkage in their tumours.

However, there were side effects, including impotency, lowered sex drive and breast tenderness.

The researchers also believe the supplement contains active anti-cancer ingredients, since it lowered PSA levels in hormone independent patients.

Dr Small's team, together with colleagues at the Dana Farber Cancer Institute in Boston, Massachusetts, are now enrolling 100 men into a new study comparing the effect of Pc-spes and oestrogen.

Prostate cancer is the second biggest cancer killer of men after lung cancer.

It kills about 9,500 British men each year and 20,000 new cases are diagnosed annually.