This clinical trial was designed to examine the pathologic outcomes of patients whose
neoadjuvant treatment course is determined using an early marker of endocrine resistance
(namely, Ki67 after 4 or 12 weeks of neoadjuvant therapy) as well as assessing clinical
outcome of patients whose disease burden after completing neoadjuvant endocrine therapy
is classified as Modified PEPI 0.
The primary and secondary objectives for the study are described below.
Primary Objectives:
1. To determine whether fulvestrant administered for 24 weeks as neoadjuvant endocrine
treatment decreases the proportion of endocrine resistant tumors* relative to
patients treated with anastrozole.
2. To determine whether fulvestrant in combination with anastrozole, administered for
24 weeks as neoadjuvant endocrine treatment, decreases the proportion of endocrine
resistant tumors* relative to patients treated with anastrozole.
3. To assess whether the 5 year RFS rate among women with a modified preoperative
endocrine prognostic index (PEPI) score of 0 following 24 weeks of neoadjuvant
anastrozole treatment is at least 95%.
4. To assess whether the 5 year RFS rate among women with a modified PEPI score of 0
following 24 weeks of neoadjuvant fulvestrant, or fulvestrant in combination with
anastrozole, is at least 95%. Note that this objective will only be tested if the
selected fulvestrant arm was shown to be superior to anastrozole in objective 1 or
2.
Endocrine resistant tumor is defined by any one of the following criteria*:
- Ki67> 10% after 4 weeks on neoadjuvant endocrine therapy
- Ki67> 10% after 12 weeks on neoadjuvant endocrine therapy
- Progressive disease is documented anytime during neoadjuvant endocrine therapy
- Surgical findings at 22-24 weeks post neoadjuvant endocrine therapy are such that:
- pT stage is 3/4
- positive lymph nodes are present or Ki67 > 2.7% (ie modified PEPI score of not
being 0)
- Discontinued neoadjuvant endocrine treatment for any reason
Secondary Objectives:
1. To assess whether the 5 year RFS rate among women with a preoperative endocrine
prognostic index PEPI score of 0 following 24 weeks of neoadjuvant anastrozole
treatment is at least 95%.
2. To examine the differences in surgical outcome, clinical and radiological response
rates, and safety profile between the fulvestrant arm and the anastrozole arm.
3. To examine the differences in surgical outcome, clinical and radiological response
rates, and safety profile between patients randomized to fulvestrant in combination
with anastrozole and those randomized to anastrozole.
4. To examine the rate of pathologic complete response (pCR) of 12 weeks of neoadjuvant
paclitaxel in patients with endocrine resistant disease following 4 weeks or 12
weeks of neoadjuvant endocrine therapy (with either fulvestrant or anastrozole or
the combination of fulvestrant and anastrozole).
5. To examine the rate of pathologic complete response (pCR) among those patients with
endocrine resistant disease, following 4 weeks or 12 weeks of neoadjuvant endocrine
therapy (with either fulvestrant or anastrozole or the combination of fulvestrant
and anastrozole), who choose not to receive neoadjuvant paclitaxel, but another
standard neoadjuvant taxane and/or anthracycline containing regimen or CMF.
6. To summarize the frequency of severe (NCI CTCAE grade > 3) adverse events
encountered with administration of paclitaxel in the neoadjuvant setting.
7. To assess RFS for patients with endocrine resistant tumors defined as: 1) Ki67 > 10%
at week 4, 2) Ki67 > 10% at week 12 and 3) modified PEPI score of non-zero on
neoadjuvant endocrine therapy, with all three groups combined or separated.