A phase II trial of green tea in the treatment of patients with androgen independent metastatic prostate carcinoma.
BACKGROUND
Recent laboratory and epidemiologic studies have suggested that green tea has antitumor effects in patients with prostate carcinoma. This Phase II trial explored green tea's antineoplastic effects in patients with androgen independent prostate carcinoma.


METHODS
This study, which was conducted by the North Central Cancer Treatment Group, evaluated 42 patients who were asymptomatic and had manifested, progressive prostate specific antigen (PSA) elevation with hormone therapy. Continued use of luteinizing hormone-releasing hormone agonist was permitted; however, patients were ineligible if they had received other treatments for their disease in the preceding 4 weeks or if they had received a long-acting antiandrogen therapy in the preceding 6 weeks. Patients were instructed to take 6 grams of green tea per day orally in 6 divided doses. Each dose contained 100 calories and 46 mg of caffeine. Patients were monitored monthly for response and toxicity.


RESULTS
Tumor response, defined as a decline >/= 50% in the baseline PSA value, occurred in a single patient, or 2% of the cohort (95% confidence interval, 1-14%). This one response was not sustained beyond 2 months. At the end of the first month, the median change in the PSA value from baseline for the cohort increased by 43%. Green tea toxicity, usually Grade 1 or 2, occurred in 69% of patients and included nausea, emesis, insomnia, fatigue, diarrhea, abdominal pain, and confusion. However, six episodes of Grade 3 toxicity and one episode of Grade 4 toxicity also occurred, with the latter manifesting as severe confusion.


CONCLUSIONS
Green tea carries limited antineoplastic activity, as defined by a decline in PSA levels, among patients with androgen independent prostate carcinoma.
Jatoi
Aminah
A
Mayo Clinic and Mayo Foundation, Rochester, Minnesota 55905, USA. jatoi.aminah@mayo.edu
Ellison
Neil
N
Burch
Patrick A
PA
Sloan
Jeff A
JA
Dakhil
Shaker R
SR
Novotny
Paul
P
Tan
Winston
W
Fitch
Tom R
TR
Rowland
Kendrith M
KM
Young
Charles Y F
CY
Flynn
Patrick J
PJ
D000368:Aged; D000728:Androgens / Q000494:pharmacology; D028241:Camellia sinensis / Q000737:chemistry*; D002277:Carcinoma / Q000188:drug therapy*; D000529:Complementary Therapies; D006801:Humans; D008297:Male; D008875:Middle Aged; D008517:Phytotherapy; D028321:Plant Preparations / Q000009:adverse effects / Q000494:pharmacology*; D017430:Prostate-Specific Antigen / Q000032:analysis; D011471:Prostatic Neoplasms / Q000188:drug therapy*; D013662:Tea; D016896:Treatment Outcome
D000728:Androgens; D028321:Plant Preparations; D013662:Tea; D017430:Prostate-Specific Antigen