Invasive DCIS

Dianna,

I'm sorry that you've been diagnosed, but I'm glad you found us here.  We've all been through it, so you'll get lots of support and help from the women on this site.  Let me start by trying to answer one of your questions:

Why oncology and/or radiation when the margins were clear?   Your surgeon's expertise is surgery; a medical oncologist is the doctor who assesses your overall condition, recommends other treatments that might be necessary, and continues to monitor you as you undergo these additional treatments and into the future. So it is normal to have both a surgeon and a medical oncologist.  Additionally, if it's determined that you will benefit from radiation, another doctor on your team will be the radiation therapy oncologist. 

As for additional treatments, radiation is usually recommended for those who have lumpectomies.  The purpose of radiation is to kill off any stray cancer cells that might be left in your breast after surgery and that could cause a recurrence.  Radiation can cut the risk of recurrence by about 50%.  Even with clean margins, there is still a chance that some cancer cells might remain - it all depends on the size of your tumor, the aggressiveness of your tumor, and most important of all, the size of your margins. After a lumpectomy, margins are usually considered "clear" if they are 2mm in size or greater.  With margins smaller than 2mm, usually a re-excision (more surgery) is recommended. So 2mm clear margins means no more surgery but with such a small margin, there is still a risk that some stray cancer cells might remain.  That's where radiation comes in.  As the margin size gets larger, the risk gets lower.  So for those who have margins that are 10mm or greater, it's possible that radiation might not be necessary.  But, if you have an aggressive tumor - grade 3 or HER2+ - then even with wide margins, radiation will be recommended. These are the factors that the oncologist and radiation oncologist will consider.

Another possible treatment is chemo.  While radiation is given to treat cancer cells that might be left in the breast, chemo is given to treat cancer cells that might have already moved into the body.  Even with clear nodes, for anyone with invasive cancer, it's possible that some cells may have escaped.  How much risk you have of this depends on your hormone status (ER, PR, HER2), the grade of the cancer and the size of the invasive tumor.  So, as Caren said, until you have your pathology report and all the details about the pathology of your cancer, it's impossible to know what your risk is, and whether chemo, or other treatments (hormone therapy, for example) might be recommended.

As for what to expect with these treatments, once you know which treatments are being considered, I'd suggest that you visit the discussion forums on this board that focus on these treatments.  There are forums for Radiation, Chemo, Hormone Therapy and one specifically for women who are HER2+.  Additionally, you may want to visit the Stage I - II Forum.  Although your diagnosis included some DCIS, there is actually no such thing as "Invasive DCIS".  Pure DCIS is a non-invasive cancer; it's Stage 0 breast cancer.  However DCIS is often found together with invasive cancer, as seems to be the case in your situation.  In those cases, the diagnosis, staging and treatment is based on the pathology of the invasive cancer - the DCIS, as the lesser condition, will be adequately treated by whatever treatments are given to address the invasive cancer.  So depending on how much of your tumor was invasive vs. DCIS, your treatment may be quite different than the treatment for pure DCIS.  As such, you may find women in a more similar situation to yours on the Stage I - II forum and that might be more helpful to you. 

I hope that helped, a bit anyway.  Good luck to you with whatever treatments lie ahead.