Wondering if an excisional biopsy, or a lumpectomy was suggested, as you state this is an in-situ ductal cancer. Have you only seen the one set of doctors regarding your diagnosis.
I believe you best source of information and advice would be your Oncologist AND your other Physicians who are treating your additional medical issues. It would also depend on whether you are considering any type of reconstruction following whichever type of surgery you are considering. Since you have serious lung issues there needs to be some cooperation between your Pulmonary Specialist and the Anesthesiologist regardless of which surgery you choose. I would also include the Radiation Specialist regarding radiation to the chest area considering your lung problems. Either way this would be a complicated situation. Regards ...