how dcis becomes invasive

Whoever figures this out for sure will be a miracle-worker for women everywhere!

It's my understanding that as it regroups in a transformation to an invasive type that it does consolidate, perhaps "eatten-up" is a good way to visualize it.

If they understood this process better, then DCIS could be treated more appropriately. Right now removing it all is the only strategy.

I think nolookingback's explanation is essentially correct. In some women with DCIS, eventually the cancerous cells within the ducts figure out how to become invasive, that is, they figure out how to break through the walls of the ducts and invade the surrounding breast tissue. Even if the DCIS is extensive, this may happen in one place first and an invasive tumor begins to grow. However, the rest of the DCIS doesn't change. It's still within the ducts. That's why there's a category of diagnosis in pathology reports that describes a situation like this as IDC (invasive ductal carcinoma) with EIC (extensive intraductal component).

Hope this helps.

Barbara

Maybe I'm misunderstanding the questions but this is what my docs told me. When the dcis is in the ducts, there's finite amount of space and so as the abnormal cells mutliply too fast you might see cell death- necrosis- because there's not enough blood supply or space for all of the new cancer cells and then maybe a breach in your immune system or maybe they are just growing too fast but the duct walls are breached, broken open and the cancer is able to spill into and multiply freely into the breast tissue itself. The part that breaks through is invasive. The parts that remain in the ducts are still DCIS. Is this what you mean? It was explained to me this way at Sloan in NY and then later by my BS at St Barnabas in NJ.

Loni-I had multifocal dcis and 3 invasive tumors but I can't answer whether if it makes it more likely. I had grades 2 and 3 and a mix of comedo necrosis and cribiform and something else. Maybe just the fact that there's a large amount makes it more likely but I would think how fast the cells were growing does too. We're all so unique in our individual cases through that I don't think this could ever have cut and dry answers.

I also agree with "nolookingbacks" explanation of it. But then can someone answer this. So do all IDC's start as DCIS? Therefore, does all women who have DCIS if not treated will turn into IDC? Also if the DCIS is contained in the duct, why are mastectomy's recommended on some? Also does all breast cancer either start in the milk duct or the lobular duct? Just trying to figure this all out.

My situation may help explain the difference between lumpectomy and mastectomy.

Originally my mammogram showed a small area of DCIS with a very small IDC invasion.  At that point my surgical oncologist suggested lumpectomy.  It was expected that they would be able to remove the small area, radiate the rest of the breast, then I would be done with only a small cosmetic change.  They sent me for an MRI just to confirm that the DCIS was a small area.  The MRI showed extensive DCIS.  There was no more invasion that they could tell, but my doctor at that point changed his recommendation to a skin sparing mastectomy.  He said that there is always a question as to whether DCIS will actually become invasive, but he felt pretty confident that if we left it I would be back in a couple of years.  At some point it becomes impossible for them to remove all cancerous tissue and leave anything cosmetically desirable behind.

This issue is a very pressing one for me, too.  I underwent a double mastectomy in June, only to be told they found 'positive margins' in the left breast tissue after it was removed.  I had no lymph node involvement.  Immediately I was being told I would now have to have radiation and chemo.  I declined both.  After studying my pathology, I realized the left breast tumor had been 80% DCIS and 20% invasive.  The right breast was all DCIS.  My 'postive margins' in my left breast tissue were positive for DCIS.  My question became this.  If I had all my breast tissue removed, including all the milk ducts, how could the straggler DCIS cells (which nobody could pinpoint the location of) suddenly become invasive.  My understanding was that DCIS needs to be able to grow within the milk ducts, etc.  I never really got a straight answer after 3 separate opinions.  My Onca test came back low intermediate and the doctors said I really didn't need the chemo.  But everyone pushed for me to have radiation.  I decided after many sleepless nights, to decline it once again.  I am under the impression if the cancer comes back, it will be palpable under the skin.  I had immediate breast reconstruction and am scheduled for my exchange surgery Dec. 3rd.  Any thoughts on this?  I read a lot online, which my doctors didn't want me to do.  But I feel confident in my decision.

It is my understanding that when they do a mastectomy they can't be sure that they got every last bit of tissue.  Obviously, they do their best, but they can't be sure.  If the margin up against the chest wall was positive, I think they want to radiate the chest wall to try to kill off any cancer cells that might have been left behind so that they can't later become invasive and spread to the chest wall. 

I had a lumpectomy and had a positive margin.  My surgeon went in for a reexcision and the new tissue didn't have any cancer in it, so he had actually gotten it all the first time.  So just because the margin was positive, doesn't necessarily mean there is cancer left behind.  They just want to make sure if there is, they radiate it. 

Kmarku,

I would have the radiation.  In fact, even though I had mastectomy, and start chemo soon, I will likely have to have rads because of close margins.

I believe you are misinformed about the way your cancer could return.  Since you had invasive components then you could have breakaway cells that could land anywhere.   One pops into your mammary lymph node and hits your lymph system and next thing you know, you have bone or brain mets.  

I'm not a doctor and my understanding of DCIS is imperfect, to say the least.  But since all of your doctors strongly suggested it was necessary, I would seriously reconsider. 

Why don't you call one and ask them that question?

In reference to the concept of DCIS being found in many women upon autopsy...the one thing we don't know is how long it has been there.  Has it been hanging out, undetected and not turning invasive for 40 years or is it recently developed?  How would we ever know?  Something *I* personally believe is that while it seems like the rate of cancer is on the rise, it may be because we are living longer, and we have eradicated many diseases that used to kill many people.  We can't all hang out on this planet forever  - and I believe that cancer is more likely to occur in an aging populace who can now be immunized against many things that used to kill us...So while cancer deaths are on the rise, deaths from other causes have dropped dramatically...

Of course this doesn't explain why people are being detected BC at *younger* ages (I was 40 @ diagnosis, myself) - but perhaps in another time I'd have died young of diptheria or something....

My Surgeon told me that with a mastectomy there is about 2% of the breast tissue left because if all of the breast tissue was to be removed then too much skin would need to be removed to do this. He told me that this was with skin sparing and non skin sparing mastectomies.

I also met a women once who had one mastectomy and then 2 years later the second mastectomy with TE and implant reconstruction and 25 years later she had another lump on the side of her foob and had to have it excised and it was BC again. She said "Who would have thought after 25 years."

You just never know. I think that we need to decrease our risk of a reocurrance as best as we can with what we can live with regarding surgery and treatments. It is really a tough choice and very personal.

Take Care,

Kerry

The radiation is specifically targeted at an angle so that it just covers the chest wall and penetrates something like a centimeter into the lung tissue.  The pre-rads workup is very involved and they take great pains to get the exact size and location of your heart, etc. so that it is not irradiated.  I know that a lot of women on this forum say they have respiratory disease and heart damage from rads, but I wonder if that has been confirmed by a doctor and if so, how careful was their rad oncologist?  I believe that was fairly common 20 years ago - I don't know what the stats are present day.

The bottom line is, if they're not sure they got everything with the mastectomy, you really need something in addition to the surgery or the stuff is going to come back. 

Desdemona-

I am very intrigued by your comment "the pathologist has a method of accurately aging the DCIS - mine was 6 years old" - I have never heard of this before - I thought all comments on how long cancer has been present were purely speculative based on size and aggressiveness.  It seems like the ability to know for certain how long malignant cells have been present would be very helpful to understanding the origins of BC...

Do you have any more information about this - I'm curious, as I haven't heard of it before....

Thanks!

For example, they knew based on the pathology report that my DCIS would have formed a palpable tumor at 8 years also.

Okay, then.  I stand corrected.  Boy, finding ANYTHING on how they age tumors on the Internet has proved very difficult at best.  Thanks for the reference.