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Tamoxifen +/- GnRH Analogue vs Aromatase Inhibitor + GnRH Analogue in Male Breast Cancer Patients

Phase 3
Completed
Conditions
Male Breast Cancer
Interventions
Registration Number
NCT01638247
Lead Sponsor
German Breast Group
Brief Summary

A prospective, randomised multi-centre phase II study evaluating the adjuvant, neoadjuvant or palliative treatment with tamoxifen +/- GnRH analogue versus aromatase inhibitor + GnRH analogue in male breast cancer patients (MALE).

Detailed Description

Breast cancer in men is a rare disease with approximately 0.5- 1% of all breast cancer cases. Each year, about 400 to 450 cases are diagnosed in Germany. Men tend to present with more advanced disease than women, probably due to the lack of awareness of male breast cancer from both, the patient and the physicians.

Therefore, at presentation they usually have lump or nipple inversion, and more than 40% of the patients have a stage III or IV disease. The great majority of patients have an invasive ductal (90%), hormone receptor positive (90%), HER2 negative (90%) tumor.

The only available information on adjuvant therapies derives from few retrospective cases and retrospective studies with a little number of cases. Therefore, treatment strategies are not based on data from prospective, randomised clinical studies, and optimal treatment is unknown. As a result, current clinical management is generally extrapolated from principles established for the treatment of female breast carcinoma. As the majority of male breast cancer patients have a hormone receptor positive tumor, they receive tamoxifen 20 mg for five years as standard endocrine adjuvant therapy. A lot of withdrawals from the treatment were documented in male breast cancer due to side-effects under tamoxifen therapy. Furthermore, the clinical outcome of tamoxifen-treated male breast cancer patients may be influenced by the activity of cytochrome P450 2D6 enzymes that catalyse the formation of anti-estrogenic metabolites endoxifen and 4-hydroxy-tamoxifen. Therefore a significant proportion of poor to moderate metaboliser is proposed to do not benefit from adjuvant tamoxifen therapy.

Although women benefit from adjuvant treatment with aromatase inhibitors (AI) regarding disease-free-survival, overall survival and treatment toxicity, only case reports of men treated with AI exist. Other data show, that under AI, there is only a suppression of estradiol of about 40-50% with an increase of testosterone of about 50%. Among men on AIs, it is possible that the hypothalamic-pituitary feedback loop results in an increase substrate for aromatisation, and thus prevents complete estrogen suppression.

However, an optimal suppression (80%) of the peripheral estradiol level would be a necessary condition for a therapeutic benefit of AI in men with breast cancer.

By adding a gonadotropin-releasing hormone analogue, the negative feedback loop would be interrupted and complete estrogen suppression may be achieved.

In conclusion, there is a great lack on information for the treatment of male patients with breast cancer.

Prospective multi-centre, randomised trials in men with breast cancer are necessary in order to prove the effect of tamoxifen + GnRH analogue versus none and versus AI + GnRH analogue as adjuvant or neoadjuvant endocrine treatment.

Recruitment & Eligibility

Status
COMPLETED
Sex
Male
Target Recruitment
56
Inclusion Criteria

Not provided

Exclusion Criteria

Not provided

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
Tamoxifen and GnRH analogueTamoxifen and GnRH analogueTamoxifen (daily) + GnRH analogue (at randomisation and after three months).
Exemestane and GnRH analogueExemestane and GnRH analogueExemestane (daily) + GnRH analogue (at randomisation and after three months).
TamoxifenTamoxifenTamoxifen alone (daily).
Primary Outcome Measures
NameTimeMethod
Estradiol blood concentation3 months.

To determine the estradiol suppression between the three treatment arms after three months.

Secondary Outcome Measures
NameTimeMethod
Efficacy6 months.

To compare the efficacy in terms of overall response (for neoadjuvant and metastatic patients) in the three treatment arms.

Efficacy perameters6 months.

To compare testosterone, dihydrotestosterone (DHT), SHBG, FSH, LH, osteocalcin and CTX in the three treatments arms.

Estradiol blood concentration6 months.

To determine the estradiol suppression between the three treatment arms after six months.

Compliance6 months.

To compare the compliance in the three treatment arms.

Safety and side effect parameters6 months.

To determine the safety and side effect parameters (at every visit):

* PSA and hemoglobin.

* Lipids (total cholesterol, high density lipid cholesterol, low density lipid cholesterol).

Trial Locations

Locations (1)

Kliniken Essen-Mitte

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Essen, Nordrhein-Westfalen, Germany

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