Going in with DCIS and coming out with invasive

I also had DCIS (<1cm) with a small invasive component, although it was smaller than yours (<1mm in my case).   My MO considers me a DCIS patient as well - he said it would have to be over 5 mm to do an oncotype test, and chemo never became part of the conversation.    I didn't have any micro-mets in my nodes but my surgeon told me before the SNB that in their practice micro-mets are considered node negative, so even if I had had one, it wouldn't have affected my treatment plan, which included a lumpectomy, whole breast radiation, and now tamoxifen.   My MO said he thought the bigger benefit to me personally from tamoxifen would be to prevent a new primary, although it should of course prevent a recurrence as well.   He basically outlined the risks and benefits and left it competely up to me as to whether to take the Tamoxifen - he would have been ok with it had I declined it.