What does it mean to have extensive DCIS?

suntree

My path. report says I have a 4 mm invasive carcinoma with extensive dcis (30% of the tumor).  Is the tumor the entire abnormal areas in the specimen or is it just the invasive part?  How can dcis be part of the invasive tumor.  An invasive tumor is no longer dcis.  This is very confusing to me.  I was told by one pathologist that extensive means that it is more than 25% and extends out beyond the tumor.  This is still confusing.  How do you know how much dcis you have unless they say how many millimeter or centimeters are seen.  There was no mention of that in the report.  Just that it is extensive and 30% .  Even my surgeon did not know how to explain it to me.  He just said that extensive just means that it is not focal. Any help would be greatly appreciated.

PhyllisCC

Suntree,

I bumped a post from "Beesie" that has lots of good info on DCIS.  May help clear up some of the confusion.  DCIS is such a confusing DX...and having 4mm invasive adds to the confusion.  The invasive takes precedence over the DCIS. What treatment options did your surgeon provide for you?

MarieKelly

It's very common to have both IDC (invasive ductal carcinoma) and DCIS within the same tumor. I had a single 1 cm tumor which was 60% invasive and the other 40% was DCIS. This is known as "IDC with an invasive intraductal component (EIC)" and as you were told, just means that the tumor was comprised of at least 25% in situ cells (DCIS). According to stats, it also means that those with an EIC have a higher risk of ipsilateral recurrence. However, I think there's a lot of additional considerations that must be taken into account because I haven't had a recurrence yet (diagnosed 5 years ago next week) despite refusing radiation after lumpectomy and also refusing any hornonal therapy.

You asked how can DCIS be part of the invasive tumor?  Well, I can certainly understand why you find this confusing because normally we think of DCIS as being completely confined to the duct system. But once cells breaks out of the ducts, those cells automatically cease to be DCIS and gets labeled as IDC. It's like having one foot outside the door while the rest of you is still on the inside of the door...still just a single body, but part of it is still inside the room and another part has moved through the door to the outside. Same with IDC with EIC...still just a single tumor, but part of it remains inside the duct system and the other part has broken through into other tissue. 

You can estimate approximately how much DCIS you have just by knowing that 30% of your 4 mm tumor is DCIS - so about 1.2 mm is DCIS.

margeb

I had extensive DCIS in my right breast but no invasive component.  After a botched sterotactic biopsy, where the needle went straight through my breast and exited on the other side, I thought that now I had invasive cancer once it escaped from the ductal membrane.  However, I was told that you could chop up the DCIS in little pieces and it still would be DCIS.  There needs to be a mutation that then makes it invasive.  One of the problems with DCIS is not knowing whose DCIS will progress to invasive and that is the reason for mastectomies when more than one area of DCIS is found. On pathology, I had 7 areas of DCIS in many quadrants of the breast.  My left breast was clear on the mamogram, ultrsound and MRI.

roseg

Once your pathology mentions invasive cancer the DCIS becomes a side issue. They'll remove it, but further treatment will be aimed at the invasive component.

Your concern should be with the invasive component, not with the DCIS because that is what is life threatening. 

Beesie

As MarieKelly explained, it's very common to have IDC and DCIS together.  The cancer starts within the milk ducts as DCIS but then a few cells break through the milk duct and those cells are now considered IDC (invasive ductal carcinoma).  It's the same cancer but the cells that are confined to the duct are called DCIS cancer cells and the cells that are outside of the ducts and in the open breast tissue are called IDC cancer cells.

I also agree with Rose.  While it's important that any breast tissue with DCIS be removed, other than that, once some IDC has been found, the DCIS becomes incidental (and virtually irrelevant) to the diagnosis.  Other than surgery, which must address both the IDC and the DCIS, the rest of your treatment and your staging will be based on the size, grade, and hormone status of the IDC.  

denilynne

Wow, I see that the last post made here was in 2009. 4 years later on Dec 13, 2013, it is still a good source of help to me. Thanks Ladies.

Mommyathome

Beesie,

Is DCIS always a Birad 6, since it's malignant? What significance is the Birad? Again my grade was low to moderate, and the size was 1.5 cm

Beesie

BIRADs is a rating given to a mammogram, an ultrasound or an MRI. The radiologist gives the BIRADs rating, based on his or her assessment of the appearance of the breast tissue on imaging. BIRADs has nothing to do with DCIS.

A BIRADs 6 is given to a mammogram, ultrasound or MRI if the imaging is done after a biopsy has already confirmed cancer. A BIRADs 6 would be given whether the known cancer is DCIS or invasive cancer.

Prior to a diagnosis, if someone has a mammogram (or ultrasound or MRI) that appears suspicious, it might be given a BIRADs 3 (less than 2% chance of malignancy; short term follow-up recommended), a BIRADs 4 (a 2% - 94% risk of cancer; biopsy recommended) or a BIRADs 5 (95% or greater chance of malignancy; biopsy required). If a biopsy is done, the findings in all of these cases might be benign, or a high risk condition like ADH or LCIS, or DCIS, or invasive cancer.

gtgirl

I must be really stupid. Really. I have seen a lot of people state DCIS stage 1 or stage IIA etc. It was my understanding that DCIS is the earliest stage Stage 0. I thought that if it isn't pure DCIS it then is Invasive Ductal Carcinoma?

MelissaDallas

you are correct. Pure DCIS is always 0. I think some get confused when they have both dcis & invasive components and don't realize the invasive "trumps" the dcis. DCIS with microinvasion moves it to 1A.

Beesie

gtgirl, you aren't stupid at all. In fact, as MelissaDallas said, you've got it exactly right. Pure DCIS is always Stage 0.

You are also right that we see a lot of women on this board who list their diagnosis as DCIS with the stage being either Stage I, or II, or III. I often try to gently correct them, but it's difficult to tell someone that they have misunderstood their own diagnosis, even if they really have.

Usually one of three things has happened. The first possibility is that they had DCIS in their biopsy, and then invasive cancer was found during their surgery. So they continue to list the diagnosis as DCIS, but they include the correct stage based on the final pathology from the surgery. The second possibility is that their pathology includes both DCIS and IDC (as happens in about 80% or 85% of cases of IDC) and they've picked up on the term "DCIS" and they list that as the diagnosis, even though the IDC trumps the DCIS and the IDC determines the stage. The third possibility is that the diagnosis is DCIS-Mi. That's my diagnosis, and although I had over 7cm of DCIS, that little 1mm microinvasion of IDC changed my staging to Stage I. The problem is that on this board, the diagnosis feature doesn't offer the option of DCIS-MI. It's either DCIS or IDC. Given that choice, most women with DCIS-Mi list their diagnosis as being DCIS, Stage I.

gtgirl

Ok, so I was understanding it correctly...!!! The end of your post, you stated "most women with DCIS-Mi list their dx as being DCIS Stage 1. So, there is two stages of DCIS?

Beesie

No, there is only one stage for DCIS. All pure DCIS is Stage 0.

But the important distinction is between a diagnosis that is pure DCIS, i.e. exclusively DCIS, and a diagnosis that includes both DCIS and invasive cancer. Most women who have IDC also have some DCIS; whenever that happens, the IDC trumps the DCIS and the cancer is considered IDC and staged as IDC.

DCIS-Mi is one of these types of mixed DCIS-IDC cancers. It is a diagnosis in which the majority of the lesion is DCIS, but there is a very small amount of invasive cancer. Therefore DCIS-Mi is not pure DCIS. Although this diagnosis could be called IDC, the name DCIS-Mi is used instead because the cancer is mostly DCIS, and because amount of IDC is no more than one or several small microinvasions (that's the "Mi" in the name; microinvasions are invasive lesions that are no more than 1mm in size). However because the name DCIS-Mi includes "DCIS", it is often grouped together with DCIS, even though it's not pure DCIS. DCIS-Mi is in fact a Stage IA invasive cancer.

The problem on BC.org is that the diagnosis feature within our personal profiles does not include "DCIS-Mi" as a type of breast cancer. So given a choice between saying that we have "DCIS" or "IDC", many women with DCIS-Mi check off the DCIS box, even though technically that's not correct. This means they end up with a diagnosis line that says "DCIS Stage I", which is incorrect. More correctly, all of us with "DCIS-Mi" should check off the IDC box, but then our diagnosis line would say "IDC Stage I" which is technically correct but can feel a bit misleading when the diagnosis is DCIS-Mi and the amount of IDC is no more than a microinvasion.