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BOSTON, MASSACHUSETTS. At present there are three major conventional treatment options for non-
metastatic prostate cancer. Expectant management essentially means to watch and see if the cancer gets
worse. Prostate tumours grow very slowly (doubling every four years) so for many men, especially older
ones, this approach is quite viable. Expectant management often includes androgen-deprivation therapy
(castration or estrogen). External beam radiotherapy involves the shrinking or destruction of the tumour by
radiation. Radical prostatectomy involves surgical removal of the entire prostate gland. This procedure
carries a substantial risk of subsequent impotence (60 per cent incidence rate) and incontinence (39 per
cent incidence rate). Researchers at several major American hospitals and universities have just released a major study of the long-term outcome of the three standard therapies. The study involved 2311 men aged 55 to 74 years at time of diagnosis during 1971 to 1984. By 1994 584 men had died from prostate cancer and 828 from other causes. The 10-year survival rate in the case of prostate cancer was 75 per cent for expectant management, 67 per cent for radiotherapy, and 86 per cent for radical prostatectomy. The researchers emphasize that these percentages are not directly comparable. For example, the members of the expectant management group were considerably older (45 per cent between the ages of 70 and 74 years) than the members of the other two groups (17 per cent between the ages of 70 and 74 years). In all cases men who underwent androgen-deprivation therapy had poorer survival than men who did not.
The results of this study differ somewhat from the results of a similar study carried out at the Johns Hopkins
School of Hygiene and Public Health. This study concluded that patients who underwent radiation therapy
had an 81 per cent higher risk of dying from prostate cancer than did men who received no treatment
(watchful waiting). Patients who received hormones or were castrated increased their risk of dying by 85 per
cent (compared with no treatment) while men who just underwent surgery with no additional treatment had a
23 per cent lower death rate (from prostate cancer) than did men who had not received any treatment. It is
not clear whether the poorer survival rate among men who had androgen-deprivation therapy is due to the
fact that this therapy is actually detrimental or due to the fact that it is preferentially prescribed for men with
more advanced cancer.
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