Benefits and drawbacks of specific approaches:
Androgen suppressive therapy plus radiotherapy
The combination of androgen suppressive therapy (medical suppression of the male hormone testosterone) and radiotherapy has been shown to improve the disease-free survival, and in some studies, overall survival, compared with radiotherapy alone (15,
25). Prostate cancer cells are usually stimulated to grow by testosterone, and suppressing it leads to the death of cancer cells, reducing the cell burden to be controlled with radiation.
To cloud the issue though, studies showing benefit to added androgen suppressive therapy tend to have in common the use of low dose and/or outdated radiotherapy technology as the control arm. Studies using high dose, contemporary radiotherapy have not routinely demonstrated added benefit from androgen suppressive therapy, presumably reflecting more complete prostate cancer cell eradication by the more contemporary radiotherapy methods and doses. (10,
11, 17, 26)
For patients with very advanced disease, whose clinical course is more likely characterized by early development of metastatic disease, long-term androgen suppressive
therapy added to the regimen may extend disease-free and overall survival even if optimal local therapy techniques are applied, likely reflecting direct suppression of metastatic deposits. For patients with early stage disease though, the added cost and side effects of added androgen suppressive therapy do not appear justified, as the disease-free survival result with local therapy alone is excellent.
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