Trial Information

Response to Neoadjuvant Treatment With Anti-aromatase Anastrozole and Anti-estrogen Fulvestrant: a Randomized Phase II Study in Postmenopausal Patients With Hormone-sensitive Nonmetastatic Breast Cancer and an Exploratory Study of Molecular Signatures of Response

OBJECTIVES:

Primary

- Evaluate clinical tumor response at 6 months in patients with hormone-sensitive
nonmetastatic breast cancer treated with neoadjuvant anastrozole vs fulvestrant.

Secondary

- Evaluate tumor regression by mammography and ultrasound in these patients.

- Evaluate the rate of breast conservation at 6 months of treatment in these patients.

- Evaluate the tolerability of these regimens.

- Estimate the progression-free survival at 5 years of these patients.

- Identify molecular signatures predictive of response in these patients.

- Identify genes implicated in response in these patients.

- Identify changes in mRNA splicing of genes involved in breast tumorigenesis.

OUTLINE: This is a multicenter study.

All patients undergo biopsy at baseline. Patients are randomized to 1 of 2 treatment arms.

- Arm I: Patients receive oral anastrozole once daily for 6 months.

- Arm II: Patients receive fulvestrant intramuscularly on days 1, 14, and 28 and then
once a month at 2-6 months.

Within 8 days after completion of hormone therapy, all patients undergo surgical resection
of the residual lesion followed by radiotherapy. Patients then receive oral anastrozole once
daily for 5 years.

Tissue samples from biopsy and surgery are analyzed to assess molecular signatures and
sensitivity to treatment, and to compare gene expression variation with response.