If DCIS spread what happens next?

I am answering blind here because only the person who holds your medical file can give definite answers, but in general, a suspected or even a confirmed spread to the SLN and any of the other nearby lymph nodes would not stop them going ahead with surgery. 

Since your cancer is at the DCIS stage there seems to be very little chance of it reaching your lymph nodes anyway, seeing it has not yet spread even within the breast area itself.

Do you have good access to your breast nurse? If so, you could reach out to her, it's worth it for peace of mind. 

Hi GreyCat - thanks for your advice. Im still a bit confused to whether you HAVE to have chemotherapy prior to surgery if its spread. I may be over thinking it but when the surgeon visited me after the SLN biopsy he warned me that we only have the original breast centre diagnosis from early Feb to go on and I have to be prepared that it could be worse. Maybe he just likes you to prepare for the worst just in case - plus I'm an over-thinker!

Re the breast cancer nurse, I think Ive fallen through the cracks here - because I went from NHS to private and then my next op will be in a completely new hospital that specialises in reconstructive surgery, I have never been given any dedicated nurse. BUPA do offer support, but I'm not sure its the same. It would be good to have a designated person at one of the hospitals for these sort of questions - you are absolutely right.

Based on the information so far, I am guessing the surgeon was referring to the possibility of a spread outside the milk ducts into the rest of the breat, but if he also meant lymph nodes, then in a way I cannot fault him for being very cautious and mentioning even the low probability scenario, while at the same time, I can see that there is a very good chance he may have scared you needlessly. 

Since you are now a private patient there should be a way for you to make contact and ask some questions to clarify. If you choose to do that, I would ask what exactly was meant by, "worse," what is the probability of this worse scenario, and whether or not there are going to be any more scans prior to surgery. If the answer to the last question is a No, then it seems surgery is to go ahead with the information they have, and then it would be up to pathology to return their findings. At that point someone should be able to say what systemic treatment may be needed. If you are back with the NHS for that, there will be a designated nurse.