I had invastive ductal carcinoma and had my entire breast removed in 2003 also - am fine still - I was stage I but from what I understand ductal carcinoma in situ is the best cancer to have - that is stage 0 - see the cancer hasn't broken yet - in situ - means it is still encapsulated so you really had the best if one were to get cancer.
Anyway, you will live a long time - just get it taken care of - have a friend who had stage 0 like you too and she just had a lumpectomy - I had a right simple mastectomy - just do whatever makes you feel good.