NEWS:PROSTATE CANCER:HORMONE BLOCKS DON’T WORK

Men with prostate cancer are unlikely to gain any real benefit from androgen suppression procedures, either surgical or pharmacological, which are aimed at controlling male hormones.

Researchers at the Netherlands Cancer Institute reviewed 27 randomised trials comparing methods of androgen suppression in the treatment of prostate cancer.

The five year survival rate in those whose treatment regime consisted of androgen suppression, using surgical castration or drugs to control testicular hormone secretion, plus an antiandrogen to block hormones of adrenal origin referred to as maximum androgen blockade, or MAB was 25.4 per cent.

This was little different from the 23.6 per cent five year survival rate of those who had only surgery or drugs to control testicular hormone secretions.

MAB is a very extreme regime in the treatment of prostate cancer. While no comment was made on the adverse effects caused by MAB, the experience of women with breast cancer suggests that hormone manipulation can produce a wide range of unpleasant effects which substantially reduce quality of life.

What is more, the results of this analysis suggest that the improvement in survival rates is minimal. According to their data, the MAB regime will only improve survival by an average about 2-3 per cent (Lancet, 2000; 355: 1491-8).

Similarly, caution is now being advised in prostate cancer regimes that involve radiotherapy. Men who have received high dose radiotherapy are now reporting side effects, including rectal bleeding, pain and mucus discharge, the possibility of which they may not be informed about at the time of receiving therapy.

The warning comes after research showing that moderate doses of conformal radiotherapy (in which the radiation strikes only the prostate and not the surrounding tissues) produces fewer rectal symptoms (Lancet, 1999; 353: 267-72).

The authors of this trial concluded that, on the basis of their findings, the radiation dose could be safely increased. However, other researchers are warning that such a recommendation cannot be drawn from the data and that routinely increasing the intensity of irradiation could end up producing just as many rectal symptoms as conventional high dose radiation (Lancet, 353; 1999: 1443).