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The Italian Breast Cancer Prevention Trial with Tamoxifen
Author(s) -
GUERRIERIGONZAGA ALIANA,
GALLI ARIANNA,
ROTMENSZ NICOLE,
DECENSI ANDREA
Publication year - 2001
Publication title -
annals of the new york academy of sciences
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.712
H-Index - 248
eISSN - 1749-6632
pISSN - 0077-8923
DOI - 10.1111/j.1749-6632.2001.tb04009.x
Subject(s) - tamoxifen , medicine , placebo , breast cancer , hormone replacement therapy (female to male) , gynecology , cancer , oncology , alternative medicine , pathology , testosterone (patch)
A bstract : The Italian Tamoxifen Prevention Study includes 5408 healthy hysterectomized women aged 35‐70 years who have been randomized to 20 mg/day of tamoxifen or placebo for 5 years. After 46 months median follow‐up, an increased risk of venous vascular events (38 women on tamoxifen vs. 18 women on placebo, P = 0.0053 ), mainly consisting of superficial phlebitis, has been observed and 41 breast cancers have occurred (19 on tamoxifen vs. 22 on placebo, P = 0.64 ). However, subgroup analyses indicated a borderline significant reduction of breast cancer among women continuously on estrogen replacement therapy (ERT, mostly transdermal) and receiving tamoxifen, with 8 cases of breast cancer among 390 ERT users on placebo versus 1 case among 362 ERT users on tamoxifen (RR = 0.13, 95% CI = 0.02‐1.02). Withdrawal rate (mainly due to menopausal symptoms) differed according to ERT use, with compliance being 78% and 75% at 3 and 5 years, respectively, for women who never took ERT, and 92% and 88% at 3 and 5 years, respectively, for women not on ERT at baseline, but who took ERT at some time during the trial. Pharmacokinetic and pharmacodynamic (surrogate end point biomarkers) studies showed that a lower dose of tamoxifen (such as 5 mg/day) does not affect the drug's activity on several biomarkers of both cardiovascular and breast cancer risk. We are therefore planning a multicenter placebo‐controlled phase III trial in postmenopausal healthy women on hormone replacement therapy (HRT) to test whether the combination of HRT and low‐dose tamoxifen retains the benefits while reducing the risks of either agent maintaining a high compliance rate.