Diethylstilbestrol diphosphate

Diethylcarbamyl chloride Diethylcarbamazine citrate Diethyl carbonate Fenspiride Flurbiprofen Furaltadone Nifuratel Protizinic acid Diethylchlorophosphate Echothiopate iodide 0 ,0i -Dlethyl-4,4 -dihydroxystilbene Diethylstilbestrol diphosphate... 

Diethylstilbestrol continues to be recommended in some centers as one of the agents of last resort when prostate cancer proves refractory to steroid hormones or androgen deprivation therapy has done all it can (1). In a Japanese study in which 16 patients were given a daily intravenous injection of diethylstilbestrol diphosphate 250 mg for 28 days, the short-term response was favorable and the drug was well tolerated (2). 

The risk of thromboembolic complications when diethylstilbestrol is used in treating prostatic cancer is well documented, but there has been some doubt as to the mechanisms involved. Oral diethylstilbestrol diphosphate 300 mg/day has been compared with LR-RH agonist therapy or no treatment in 35 patients with prostatic cancer (5). Diethylstilbestrol reduced the concentrations of protein S to below the lower limit of normal in 24 of the 35 cases. There was also some reduction in antithrombin III concentrations. These results were consistently confirmed in a follow-up group of eight further patients who took diethylstilbestrol. Since these very low concentrations of protein S are virtually the same as those found in congenital deficiency, it seems likely that this plays a role in the development of cardiovascular complications during diethylstilbestrol treatment. 

The parenteral formulation diethylstilbestrol diphosphate is less commonly used than the oral formulation. In Japan, 24 elderly patients with advanced relapsed prostatic cancer were treated with high doses supplemented with ethi-nylestradiol (doses unclear) there was some slight therapeutic effect, but there were gastrointestinal symptoms and fluid retention (48). Also in Japan, a few patients with advanced disease were treated using intravenous diethylstilbestrol diphosphate 500 mg/day for 20 consecutive days to a total dose of 10 g the authors conclusion was more positive but adverse events were not specified (49). 

Takezawa Y, Nakata S, Kobayashi M, Kosaku N, Fukabori Y, Yamanaka H. Moderate dose diethylstilbestrol diphosphate therapy in hormone refractory prostate cancer. Scand J Urol Nephrol 2001 35(4) 283-7. 

Hayashi N, Wada T, Ikemoto I, Oishi Y, Suzuki H, Ueda M. Decrease in anticoagulant factors in patients with prostate cancer treated with diethylstilbestrol diphosphate. Nippon Hinyokika Gakkai Zasschi 2003 94 420-7. 

Hisamatsu H, Sakai H, Kanetake H. High-dose intravenous diethylstilbestrol diphosphate (DES-DP) in the treatment of prostatic cancer during relapse. Nioshinihon J Urol 2002 64 199-202. 

Michinaga S, Ariyoshi A. High-dose intravenous diethylstilbestrol diphosphate therapy for hormone-refractory prostate cancer. Nishinihon J Urol 2002 64 203-5. 

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