Tamoxifen for flutamide/finasteride-induced gynecomastia
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1Department of Urology, St. Luke's-Roosevelt Hospital Center, New York, NY 10019, USA.
Objectives:
Current therapies for advanced prostate carcinoma lead to a marked decrease in serum testosterone levels, which renders patients impotent. In preliminary studies, combination therapy with flutamide and finasteride has been used as an alternative therapy for the treatment of prostate carcinoma because potency can be preserved. Both of these agents can cause gynecomastia and breast/nipple tenderness.
Methods:
Six men being treated for advanced prostate carcinoma with flutamide/finasteride combination therapy developed painful gynecomastia, which was treated with tamoxifen 10 to 30 mg/day for 1 month. Clinical follow-up included breast measurements and determination of prostate-specific antigen (PSA), testosterone, and estradiol levels.
Results:
While on this combination therapy for prostate carcinoma, 4 of 6 patients experienced a decrease in PSA level to less than 0.5 ng/mL. All patients remained potent. Serum testosterone increased in each patient who had a baseline level drawn. Estradiol levels were noted to be elevated in 4 of 6 patients at the time of evaluation for gynecomastia. After treatment with tamoxifen, circulating estradiol levels increased in 3 patients from 1.3 to 2.2 times the baseline level. Five patients experienced complete resolution of breast and nipple pain on tamoxifen 10 mg/day within the first month. The other patient had to be treated with 30 mg/day for 1 additional month, which subsequently resulted in pain resolution.
Conclusions:
These preliminary results suggest that low-dose tamoxifen is useful in treating painful gynecomastia for those patients on flutamide/finasteride combination therapy for advanced prostate carcinoma.
Insights
Low-dose tamoxifen effectively treats painful gynecomastia in prostate cancer patients undergoing flutamide/finasteride therapy. This approach helps preserve potency while managing side effects like breast tenderness.
Area of Science:
- Oncology
- Endocrinology
- Urology
Background:
- Advanced prostate carcinoma treatments often cause impotence due to decreased testosterone.
- Flutamide and finasteride combination therapy preserves potency but can lead to gynecomastia and breast tenderness.
Purpose of the Study:
- To evaluate the efficacy of tamoxifen in managing painful gynecomastia in patients with advanced prostate carcinoma receiving flutamide/finasteride therapy.
Main Methods:
- Six patients with advanced prostate carcinoma experiencing painful gynecomastia were treated with tamoxifen (10-30 mg/day).
- Clinical assessments included breast measurements and monitoring of prostate-specific antigen (PSA), testosterone, and estradiol levels.
Main Results:
- Four of six patients achieved a PSA level below 0.5 ng/mL.
- All patients maintained potency, and testosterone levels increased in those with baseline measurements.
- Tamoxifen treatment led to complete resolution of breast and nipple pain in five patients within one month.
Conclusions:
- Low-dose tamoxifen is a potentially useful treatment for painful gynecomastia associated with flutamide/finasteride combination therapy for advanced prostate carcinoma.
- Tamoxifen may help mitigate side effects while maintaining therapeutic benefits of the combination therapy.
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