Written by Liene Dhooghe and the CAM-Cancer Consortium.
Updated February 8, 2017

PC-SPES

Is it safe ?

Adverse events

Several adverse events were observed. It is, however, possible that some toxic effects were caused by the synthetic drugs, such as warfarin and diethylstilbestrol that were found in PC-SPES samples25.

In studies and trials the following adverse effects were observed: gynecomastia was near universal; leg cramps, nipple tenderness, loss of libido and impotency were common; less common were nausea and vomiting; and uncommon adverse effect was thromboembolism6,8,26,27.

Several case reports of toxic effects of PC-SPES were published. The more serious complications include pulmonary embolism and disseminated intravascular coagulation21,22,28.

Contraindications / interactions

Because of the estrogenic effects of PC-SPES, it might interfere with conventional hormone therapies for prostate cancer if used concurrently4. Nevertheless, there are no reports on contraindications or important drug-herb interactions so far26. As long as not every ingredient is identified, it is, however, difficult to assess reliably any contraindication or risk of herb-drug interactions.

Warnings

Withdrawal response to PC-SPES was noted, in spite of previous experience suggesting a rapid rise in PSA after discontinuation of the PC-SPES therapy23,29.

Quality issues

The manufacturers have failed to control the quality of PC-SPES and to apply good manufacturing practices (GMP) during its production leading to its contamination with diethylstilbestrol and ethinyl estradiol 16,17 as well as warfarin and indomethacin 18.

Citation

Liene Dhooghe, CAM-Cancer Consortium. PC-SPES [online document]. http://cam-cancer.org/The-Summaries/Herbal-products/PC-SPES. February 8, 2017.

Document history

Assessed as up to date in February 2017 by Barbara Wider.
Assessed as up to date in January 2015 by Barbara Wider.
Assessed as up to date in August 2013 by Barbara Wider.
Summary first published in January 2012, authored by Liene Dhooghe.

References

  1. Blumenthal M. The rise and fall of PC-SPES: New generation of herbal supplement, adulterated product, or new drug? Integrative Cancer Therapies 2002;1(3):266-270.
  2. Sovak M, Seligson AL, Konas M, Hajduch M, Dolezal M, Machala M, Nagourney R. Herbal composition PC-SPES for management of prostate cancer: Identification of active principles. Journal of the National Cancer Institute 2002;94(17):1275-1281.
  3. Natural Treatments for Prostate Cancer (available on the internet). As example: http://health.groups.yahoo.com/group/natural_prostate_treatments/message/19573 accessed 8 February 2017.
  4. Lee CO. Complementary and alternative medicine patients are talking about: PC-SPES. Clinical Journal of Oncology Nursing 2005;9(1):113-114.
  5. Shabbir M, Love J, Montgomery B. Phase I trial of PC-spes2 in advanced hormone refractory prostate cancer. Oncology Reports 2008;19:831-835.
  6. Kosty MP. PC-SPES: Hope or hype? Journal of Clinical Oncology 2004;22(18):3657-3659.
  7. Yip I, Cudiamat M, Chim D. PC-SPES for treatment of prostate cancer: Herbal medicine. Current Urology Reports 2003;4:253-257.
  8. Marks LS, DiPaola RS, Nelson P, Chen S, Heber D, Belldegrun AS, Lowe FC, Fan J, Leaders FE, Pantuck AJ, Tyler VE. PC-SPES: Herbal formulation for prostate cancer. Urology 2002;60(3):369-375.
  9. Meyer JP, Gillat DA. PC-SPES: A herbal therapy for the treatment of hormone refractory prostate cancer. Prostate Cancer and Prostatic Diseases 2002;5:13-15.
  10. DiPaola RS, Zhang H, Lambert GH, Meeker R, Licitra E, Rafi MM, Zhu BT, Spaulding H, Goodin S, Toledano MB, Hait WN, Gallo MA. Clinical and biological activity of an estrogenic herbal combination (PC-SPES) in prostate cancer. The New England Journal of Medicine 1998;339(12):785-791.
  11. Pfeifer BL, Pirani JF, Hamann SR, Klippel KF. PC-SPES, a dietary supplement for the treatment of hormone-refractory prostate cancer. BJU International 2000;85:481-485.
  12. de la Taille A, Hayek OR, Buttyan R, Bagiella E, Burchardt M, Katz AE. Effects of a phytotherapeutic agent, PC-SPES, on prostate cancer: A preliminary investigation on human cell lines and patients. BJU International 1999;84:845-850.
  13. de la Taille A, Buttyan R, Hayek O, Bagiella E, Shabsigh A, Burchardt M, Burchardt T, Chopin DK, Katz AE. Herbal therapy PC-SPES: In vitro effects and evaluation of its efficacy in 69 patients with prostate cancer. The Journal of Urology 2000;164:1229-1234.
  14. Small EJ, Frohlich MW, Bok R, Shinohara K, Grossfeld G, Rozenblat Z, Kelly WK, Corry M, Reese DM. Prospective trial of the herbal supplement PC-SPES in patients with progressive prostate cancer. Journal of Clinical Oncology 2000;18(21):3595-3603.
  15. Oh WK, George DJ, Hackmann K, Manola J, Kantoff PW. Activity of the herbal combination, PC-SPES, in the treatment of patients with androgen-independent prostate cancer. Urology 2001;57(1):122-126.
  16. Oh WK, Kantoff PW, Weinberg V, Jones G, Rini BI, Derynck MK, Bok R, Smith MR, Bulbey GJ, Rosen RT, DiPaola RS, Small EJ. Prospective, multicenter, randomized phase II trial of the herbal supplement, PC-SPES, and diethylstilbestrol in patients with androgen-independent prostate cancer. Journal of Clinical Oncology 2004;22(18):3705-3712.
  17. Guns ES, Goldenberg SL, Brown PN. Mass spectral analysis of PC-SPES confirms the presence of diethylstilbestrol. The Canadian Journal of Urology 2002;9(6):1684-1688.
  18. Ko R, Wilson RD, Loscutoff S. PC-SPES. Urology 2003;61:1292-1292.
  19. Walsh PC. Editorial comment on “Prospective, multicenter, randomized phase II trial of the herbal supplement, PC-SPES, and diethylstilbestrol in patients with androgen-independent prostate cancer”. The Journal of Urology 2005;173:1966-1967.
  20. de la Taille A, Hayek OR, Burchardt M, Burchardt T, Katz AE. Role of herbal compounds (PC-SPES) in hormone-refractory prostate cancer: Two case reports. The Journal of Alternative and Complementary Medicine 2000;6(5):449-451.
  21. Olaku O, White JD. Herbal therapy use by cancer patients: A literature review on case reports. European Journal of Cancer 2011;47:508-514.'
  22. Lock M, Loblaw DA, Choo R, Imrie K. Disseminated intravascular coagulation and PC-SPES: A case report and literature review. The Canadian Journal of Urology 2001;8(4):1326-1329.
  23. Oh WK, George DJ, Kantoff PW. Rapid rise of serum prostate specific antigen levels after discontinuation of the herbal therapy PC-SPES in patients with advanced prostate carcinoma: report of four cases. Cancer 2002;94(3):686-689.
  24. Moyad MA, Pienta KJ, Montie JE. Use of PC-SPES, a commercially available supplement for prostate cancer, in a patient with hormone-naive disease. Urology 1999;54(2):319-323.
  25. Weinrobe MC, Montgomery B. Acquired bleeding diathesis in a patient taking PC-SPES. The New England Journal of Medicine 2001;345(16):1213-1214.
  26. Cordell GA. PC-SPES: A brief overview. Integrative Cancer Therapies 2002;1(3):271-286.
  27. Das P, Kaplan I. The role of PC-SPES, selenium, and vitamin E in prostate cancer. Oncology 2002;16(3):285-291.
  28. Schiff JD, Ziecheck WS, Choi B. Pulmonary embolus related to PC-SPES use in a patient with PSA recurrence after radical prostatectomy. Urology 2002;59(3):444vii-444viii.
  29. Chaudhary UB, Rashid M, Keane TE. PC-SPES withdrawal response. Acta Oncologica 2004;43:772-773.