Described herein are methods of treating non-metastatic castrate-resistant prostate cancer with anti-androgens. Specifically, the present invention provides the use of a compound: 4-[7-(6-cyano-5-trifluoromethylpyridin-3-yl)-8-oxo-6-thioxo-5,7-diazaspiro[3.4]oct-5-yl]-2 fluoro-N-methylbenzamide, 4-(3-(4-cyano-3-(trifluoromethyl)phenyl)-5,5-dimethyl-4-oxo-2-thioxoimidazolidin-1-yl)-2-fluoro-N-methylbenzamide, or 4-[7-(4-cyano-3-(trifluoromethyl)phenyl)-8-oxo-6-thioxo-5,7-diazaspiro[3.4]oct-5-yl]-2-fluoro-N-methylbenzamide, in the manufacture of a medicament for treating non-metastatic castration-resistant prostate cancer, in a male human, wherein the medicament is to be used in combination with orchiectomy.
