Chance of IDC Inside Lump in DCIS core biopsy

Tryn2staycalm - there are no statistics on this as we are all different. All you can realistically do is wait for the path to come back. Take a deep breath and don't drive yourself crazy trying to search for stats that aren't there, develop a case of "google-itis", spend all day on BCO. If you do this, you will go crazy.

For me the waiting was the hardest part. Unfortunately, that's where you are now.

((((Gentle HUGS))))))

I'm someone who finds comfort and understanding in stats, so let me try to answer your question.  Of all women diagnosed with DCIS via a needle biopsy, approx. 80% will have a final diagnosis of pure DCIS, i.e. Stage 0 breast cancer.  The remaining 20% will be found to have something more.  In most cases (about 75% of that 20%, i.e. in around 15% of situations), all that is found is a microinvasion or two of IDC.  While that does change the staging to Stage I (tumor size T1mic), the good news is that with only a microinvasion, the treatment plan will usually be exactly the same as it would be for pure DCIS.  The exception is that a sentinel node biopsy would need to be done on the lymph nodes. Often SNBs are done for those who have pure DCIS but with DCIS checking the nodes is optional whereas if there is any IDC present, even just a microinvasion, checking the nodes becomes necessary.  In the remaining 5% of cases (of that 20% who end up with something more than pure DCIS), either a larger amount of IDC is found or there is nodal involvement (possibly as a result of a microinvasion - lymph node invasion is found in approx. 10% of cases where microinvasions have been found).

So, based on averages, there is an 80% chance that your next surgery will find only more DCIS.  And there is a 95% chance that your final diagnosis will be either pure DCIS or DCIS with a microinvasion, and nothing more serious than that.  

I hope that helps and is reassuring to you!

Oh holy moly, tryn2staycalm, I have had a similar question myself, so I was very interested to read your thread. I then clicked on your name to find more recent posts of yours -- to see what happened -- and discovered that you had a large amount of IDC after all! I'm so sorry!!

(And now also worried for myself as I'm in this torturous waiting game before surgery (mastectomy) for my extensive DCIS "with possible microinvasion".)

I hope you are doing okay?

localgirl,

The diagnosis that you have now, based on the core needle biopsy, is a preliminary diagnosis. When you have your next surgery, all the breast tissue that is removed will be analysed in the lab and you will get another pathology report.  If the surgical margins are clear, then this will be your final surgery and your official diagnosis will be determined based on what was found in both the core needle biopsy and the surgery.  If the surgical margins aren't clear, then more surgery may be necessary.  In that case, the process will be the same - any breast tissue removed during the surgery will be analysed and another pathology report will be prepared.  Your official diagnosis will be based on what was found in all the surgeries. 

In about 80% of cases where DCIS is found during a needle biopsy, the final diagnosis will still be DCIS.  In other words, all that will be found in the breast tissue that is removed during the surgeries will be more DCIS.  But in about 20% of cases, some invasive cancer will be found in the breast tissue that's removed during the surgery.  If that happens, the diagnosis changes and is no longer DCIS. 

What it comes down to is that you don't know for sure what your final diagnosis is until all your surgery is completed and all the pathology reports are available.  There is no way to make a final diagnosis from a biopsy, or from what's seen on the screening films, or from what the doctor may see during surgery.  Unfortunately you always have to wait for the pathology report.  If you have lymph nodes removed, sometimes they are checked in the lab while you are surgery, but this is still only a preliminary check.  The final word on whether the nodes are clear or not won't be known until the pathology report is available.

Waiting is the worst....had a big hematoma from the the biopsy which showed DCIS...so its been almost six weeks and I have still not had surgery. Hopefully it will be this week. Anyone know around how long it takes for the pathology reports to come back from a lumpectomy?

jpthelen, So sorry you have the IDC invasion. I know in my case my SNB was done as an out patient surgery. Mine was done at the same time as my lumpectomy, but I do know there are women on BCO that had it done as a separate procedure. As far as the path report, yes  you will have another path report. I know at the time of my surgery I was told the SNB appeared negative, but the final report would come later.