DCIS Margins

I have bilateral intermediate grade DCIS (1.5 cm on left, .5 cm on right).  After a number of surgeries I have +1cm margin on right, but around 2mm margin on the left.  On the right I have ADH transected at the specimen.  On both right and left I have plenty of other proliferative changes including atypical lobular hyperplasia, more ADH, cysts, adenosis, fibroadenoma, etc.

I am preparing for bilateral radiation but concerned over the margin on left and remaining ADH on right.  I am 48 and the DCIS is ER and PR positive, so I would take Tamoxifen.

Am I at an increased risk of local recurrence based on 2 mm margin, my age (premenopausal) or known ADH remaining in breast or does the whole breast radiation take care of these issues (well, except for the age)?  

Thanks.

[Dennis MD]

Hi.
Ductal Carcinoma In Situ (DCIS) can be treated by:  excision plus radiotherapy, excision alone, or mastectomy.  Hormonal therapy in the form of tamoxifen can also be given in DCIS.  There is currently no consensus regarding the optimal treatment of DCIS.
A 1-2 mm margin can be considered adequate provided adjunctive radiotherapy is going to be given.  If you will not undergo radiotherapy, the margin should be at least 10 mm.  Studies show that there is about 40-50% risk reduction for local recurrence if radiotherapy is given after breast conserving surgery.