Is there a recommended follow-up tx for apocrine ca in situ after radiation?

I recently had a lumpectomy for apocrine ca in situ.  No lymph node involvement.  Followed by standard radiation tx.  Since this tumor is not estrogen sensitive, would there be any value in taking tamoxifen or arimidex?  I understand that in addition to being estrogen blockers, these drugs also have a possible anti ca effect in general.  I am 56 and had been a smoker for many years and now feel that I may be more susceptible to ca in the future since this recent diagnosis.

[CCF-RN,MSN-rf]

Dear clj:  There is no evidence that tamoxifen reduces recurrence or improves survival in estrogen receptor negative breast cancer.  In fact, a study in 1999 indicated that recurrence may actually be higher in estrogen receptor negative breast cancer patients taking tamoxifen.  This is true even though there is some evidence that tamoxifen may decrease the incidence of breast cancer in the opposite breast.  You should certainly have a risk/benefit discussion with your doctor before considering taking tamoxifen.  Arimidex is approved for metastatic disease in estrogen receptor positive, post menopausal women.  It would not be appropriate in your situation.