treats Prostate cancer
EvidenceDISCLAIMER: These uses have been tested in humans or animals. Safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider.
Uncontrolled human studies of PC- SPES® have reported improvements in patients with both androgen- dependent
and androgen- independent prostate cancer. Overall, these studies found prostate- specific
antigen (PSA) levels to fall by greater than 50% in most patients as well as improvements in bone scans and X- rays, reductions in pain scores, and improvements in quality of life. In a 2002 preliminary report (conference abstract) of a comparison between PC- SPES® and diethylstilbestrol (DES) in patients with
androgen- independent metastatic prostate cancer, patients treated
with PC- SPES® had a greater reduction in PSA
levels. However, the later finding that undeclared amounts of DES are present in some PC- SPES® samples clouds these results.
Various explanations for the effectiveness of PC- SPES® were initially proposed. Estrogen- like effects were reported prior to 1998. These may be due to herbs with estrogen- like effects or to undeclared estrogenic drugs. The constituent baicalin, a flavone found inScutellaria baicalensis, was found in laboratory experiments to inhibit the enzymes 12- lipoxygenase,
5- alpha- reductase, and aromatase. In addition, PC- SPES® extracts were reported to cause cell death (apoptosis) or to slow the growth of cancer cell lines.
The recent finding that different lots of PC- SPES® produced between 1996 and 2001 contained different ingredients from each other has raised questions about whether studies of PC- SPES® can be compared with each other. The discovery of undeclared prescription drug ingredients including the non- steroidal anti- inflammatory drug indomethacin, the synthetic estrogen diethystilbesterol (DES), the estrogen ethinyl estradiol, and the anticoagulant warfarin, make it unclear if these constituents may have caused the observed clinical effects.
Because of these complicated circumstances, and the fact that PC- SPES® has never been compared to placebo or standard cancer treatments in a well- reported study, the question of effectiveness remains unclear.
Due to known and theoretical safety concerns, samples of PC- SPES® that may be in the possession of patients should not be used.