help me understand dcis

bcisnofun,

If someone had positive nodes, then they did not have pure DCIS.  They might have had some DCIS but they also had to have some invasive cancer along with that DCIS.  DCIS cannot travel to the nodes. Even if no invasive cancer is found in the breast, when there is cancer in the nodes it is assumed that there was an occult invasion (i.e. invasive cancer in the breast tissue that wasn't found). 

As for those who become Stage IV, again in most cases it's someone who's diagnosis was not pure DCIS - they also had an invasive component right from the start.  Most cases of IDC also include some DCIS and for some reason the term "DCIS" seems to stick out when doctors tell patients about their diagnosis or when patients read their pathology reports.  As a result, it's not unusual to see women here who say that they have "DCIS Stage I" or "DCIS Stage III".  What they have is actually IDC Stage I or IDC Stage III and along with the IDC, they have some DCIS. If any of these women progress to Stage IV, from how they've described their diagnosis it will appear that they started with DCIS and progressed to Stage IV but in fact they really didn't start with pure DCIS.

Another situation is those who have DCIS-Mi.  That's DCIS with a microinvasion.  That's my diagnosis.  A microinvasion is invasive cancer, but it's just a tiny amount.  It changes the diagnosis to Stage I, whereas pure DCIS is always Stage 0.  But this isn't always explained to women who have a microinvasion so they continue to believe and state that their diagnosis is DCIS and they are Stage 0. But again in actual fact they started out as Stage I, with a very tiny amount of invasive cancer.  And with that very tiny amount of invasive cancer comes a very tiny risk of mets.

For those who really do start off with pure DCIS, if there is a local (in the breast area) recurrence, in approx. 50% of cases the recurrence is not found until the DCIS has evolved to become invasive cancer.  So at that point the diagnosis and prognosis changes and the development of mets is a possibility.

Lastly, in rare situations, it's possible that someone might be diagnosed with what appears to be pure DCIS, however there actually was some invasive cancer present that was not found when the breast tissue was analysed (an occult invasion). So this individual - and her doctors - believe that the diagnosis is Stage 0 DCIS when it fact that really isn't the case.  It's a misdiagnosis. Usually the amount of IDC that is missed in the pathology is very very tiny and doesn't create any problems. It's removed along with all the DCIS and that's the end of it. But if a few of these invasive cancer cells escaped into the body before the cancer was removed from the breast, then at some point in the future mets could develop.  In my almost 6 years on this board, I think I've seen this happen only in 2 cases.  In every other case where it appears that DCIS progressed to Stage IV, what really happened could be explained by one of the other situations that I mentioned.

Thanks, Beesie - that very good explanation helps me, too!

Officially even one chocolate chip in the middle of a lot of oatmeal means that it's no longer an oatmeal cookie.  It is an "oatmeal chocolate chip cookie".  I had 1mm of IDC in the middle of over 7cm of DCIS and my diagnosis was DCIS-Mi (DCIS with a microinvasion), which is Stage I.  That how all the official staging documents show it. 

But, as cycle-path said, often "the doc tells the patient she has whatever s/he thinks will give the patient the most peace of mind, or motivate her to get the right treatment" and that's why some docs choose to not mention the "Stage I" part.  It's also pretty easy, when talking about "DCIS with a microinvasion" to just abbreviate and say "DCIS".  The treatment and prognosis is virtually the same so in most cases the doc may feel that there is little harm done.  The harm only comes if the patient does not understand that there is a very small difference between pure DCIS and DCIS-Mi and that difference is the very small risk of mets that comes from having the microinvasion.

My doctor told me immediately that I had the microinvasion and that this moved the diagnosis up to Stage I.  He went on to explain that in all likelihood this microinvasion would have no impact on my treatment or long-term prognosis. I appreciated having my diagnosis explained to me correctly and I wish that all doctors would do that. They should not treat their patients like idiots nor should they try to think about what explanation might be easier on someone. They should tell the truth. And the truth is that even the tiniest presence of IDC means that the diagnosis is not Stage 0 DCIS.  

My pathology report indicates that I had DCIS along with Paget's disease, which is apparently a rare form of cancer of the nipple associated with either DCIS or an underlying cancer.  I have been very confused because everyone says 'oh that is only stage 0 - the kind that doesn't spread'. Yet, the surgeon also recommended that I have the whole breast removed.  Following surgery I was advised that had I opted for only partial removal with radiation, I would have ended up having to have a second surgery to remove the rest of the breast.  If DCIS doesn't spread, then why is it treated the same as other cancer?  Very confused  

Oh, yes, if DCIS becomes invasive it is no longer DCIS but IDC.

Djustme, I'm not surprised that you are confused.  It is true that pure DCIS is Stage 0 and that it "can't spread". But it is also true that many women diagnosed with DCIS require mastectomies.  That's what was recommended for you, that was sunshinegal's situation, and that was my situation too. In my case there was simply too much DCIS (over 7cm in a small breast) to be able to remove it all with just a lumpectomy.  A mastectomy was necessary.

So if DCIS can't spread, why did we all require mastectomies?  Let me try to explain. DCIS cells are cancer cells. Cancer cells by definition tend to multiply and spread. DCIS cancer cells are no different. The more aggressive the DCIS (higher grade, the presence of comedonecrosis), the more likely it is that the DCIS cells have been busy multiplying and spreading.  But... and here's the big difference with DCIS vs. invasive cancer... DCIS cancer cells are confined to the milk ducts.  So what this means is that as DCIS cancer cells multiply and spread, the only place that these cells can move and expand into are other milk ducts in the breast.  There are milk ducts throughout the breast, so as the cells multiply, DCIS tends to become more and more spread out through the ductal system of the breast.  The DCIS cancer cells are always remain confined to the milk ducts - they never enter the open breast tissue - but within the ductal system of the breast, the DCIS cells can spread.

This is the reason why aggressive DCIS often tends to cover large areas of the breast, more so than invasive cancer.  With invasive cancer (IDC), the cancer cells are in the open breast tissue, and this means that they can multiply and expand in place, forming an ever increasing lump. Or the cancer cells can travel around and move into the nodes or the vascular system (bloodstream). That's the type of spread - into the nodes and vascular system - that is the most dangerous, because from there the cells can move to another part of the body and take hold there. That's metastisis.  And that's not possible with DCIS because DCIS cancer cells can only spread out within the confined space of the ductal system in the breast. 

What this means for DCIS patients is that DCIS is more likely than IDC to be widespread throughout the breast and as a result, it may be harder to get clean margins with a lumpectomy. A mastectomy is more likely to be required. So although it seems counter-intuitive, this is why mastectomies are considered to be 'medically necessary' more often for DCIS patients than those with IDC.  

To your other question, the reason that DCIS is treated the same as other breast cancer is because cells that are DCIS today could become IDC (invasive cancer) cells in the future.  Cancer starts with a normal cell.  This cell starts to mutate.  First it becomes 'atypical' - it's a bit different than a normal cell but it's not a cancer cell and it doesn't have the properties of a cancer cell (it's not going to spread out of control, as cancer cells can). If it continues to evolve, it next becomes a pre-invasive cancer cell - in breast cancer, that's a DCIS cell. DCIS cells have most of the properties of invasive cancer except that the cell has not yet acquired the ability to break through the milk duct and survive in open tissue. What that means is that DCIS cells cannot survive outside of the breast. But again the cell can continue to evolve. And if the DCIS cell undergoes one more biological change, then it becomes invasive cancer -it's no longer DCIS but is now IDC. That's the point at which the cell has the capability to move outside of the breast. And that's why DCIS is treated like any other breast cancer, at least in that the DCIS cells have to be removed. Those very same DCIS cells could one day become IDC cancer cells so you want to get them out before they become more dangerous.  

And just to clarify one other point.  A diagnosis of pure DCIS is always Stage 0.  According to the official staging documents, anyone who has a combination of DCIS and IDC - even if they have a lot of DCIS and only a tiny amount of IDC - does not have 'pure' DCIS and therefore will not be Stage 0. The tiniest amount of invasive cancer, or the presence of nodal involvement (even if no invasive cancer was found) changes the diagnosis to at least Stage I. In my case, I had 7+ cm of DCIS. In one small area those DCIS cells had started to undergo that next biological change and 1mm of the cells had broken through the milk duct and become IDC. Because of that, my diagnosis was not DCIS, it was DCIS-Mi, Stage I (Mi stands for microinvasion, which is the term used for a 1mm or smaller area of IDC). Or I could just say that I had Stage I IDC.  What I should not say is that I had DCIS or DCIS Stage 0 because that implies pure DCIS, which is not what I had.  

Hope that helps and isn't too confusing!  

Although you will find different terms and opinions that can be very confusing--

the answer to your question (according to the vast majority of experts) is, "Yes, you had cancer.  DCIS is pre-invasive / non-invasive cancer." 

Paget's disease is classified along with the underlying cancer, DCIS in your case.

Here's what the main Breastcancer.org site has to say about DCIS - Ductal Carcinoma In Situ.

Judith and the Mods

Djustme, yes, I have had others minimize my diagnosis (not even knowing it was "just" DCIS - just knowing it was breast cancer in general).  It hurts, for sure.  In my situation, I realized that what they were doing was, in a warped way, trying to make me feel better.  By making light of the situation, it makes it less scary for them, and so they think that is a way to help you.  They don't realize that what we want instead is for someone to VALIDATE our feelings.  It helps to realize it is THEIR issue, they can't deal with the seriousness of our diagnosis.  It still hurts, but I found understanding why they are saying those things keeps me from slugging them.  LOL.  Really, though, if she continues to say that, I would be inclined to say to her "please don't minimize my loss and struggle.  I know you think you are helping by downplaying what I am going through, but it actually makes me feel much worse."

Can you explain to me why my pathology says "negative for DCIS component"?

I would assume because you had 100% IDC with no DCIS. Did you have reason to believe you had some DCIS?

melster,

Keep in mind too that a core biopsy only retrieves a sample of the cancerous tissue.  It's true that in about 90% of cases, DCIS and IDC are found together.  But that doesn't mean that a needle biopsy sample will pick up both DCIS and IDC.   As cycle-path suggested, it appears that your biopsy sample showed only IDC.  That doesn't mean that some DCIS might not be found once the full area of cancer is removed.

My needle biopsy only found ADH.  My subsequent surgery found ADH, DCIS (and every type of DCIS - solid, papillary, micropapillary, cribiform, comedo and comedonecrosis), and a microinvasion of IDC.

In any case, because you have been diagnosed with IDC, if any DCIS ends up being found, it won't make any different to your diagnosis, your treatment or your prognosis. It will just need to be removed. The IDC is the more serious condition and your treatment plan is developed for that. Any DCIS that may be found will simply become a comment on a pathology report.  

Melster, an MRI is unlikely to be able to distinguish between DCIS and IDC. That's not what it's for. The MRI shows the tumor but it can't tell the pathology of the tumor such as grade, whether there's any necrosis, and the type of tumor cells found. That information is determined by the pathologist who examines the tissue removed when a biopsy or surgery is done.

I saw a similar post from you on another thread. Unfortunately I'm not much on the statistics. I was told that radiation would halve my chance of recurrance, and I never looked further into the statistics than that.

My suggestion is that you create a new thread, either in the DCIS section or the Radiation section. Title it something like "looking for statistics on recurrence with/without radiation." I think you'll get some answers if you do that. 

Edited to add: never mind! You got great answers from Beesie below. 

stac, I'll try to dig up some info on recurrence rates with and without radiation for you but the thing that you have to keep in mind is that every case is different.  I remember reading one study that said that recurrence risk after a lumpectomy for DCIS can range from 3% to 60%.  What this means is that some women start off with a very low recurrence risk post-surgery and for them there is little benefit from radiation and little risk if they choose to not have radiation.  Other women face a much higher recurrence risk after surgery and therefore these women will get a much greater benefit from radiation. Generally, most studies have shown that whatever the starting risk level, radiation reduces the risk by about 50%.

The key factors that play in your individual recurrence risk are:

- size of the area of DCIS; this can be estimated before surgery but it's something you really don't know for sure until after surgery - all the DCIS that's there might not show up on the mammo or even an MRI.

- focality of the DCIS; do you have a single focus of DCIS or is it multi-focal?  This might show up on the films before surgery but here again there could be surprises after surgery.  You may think that there was a single focus of DCIS only to find out that there were additional areas. 

- aggressiveness of the DCIS (grade and whether or not there is any comedonecrosis present); you may have a complete picture of this from the biopsy but you won't know that until you get your final pathology report and see if anything new/different was discovered

- the size of the surgical margins; this is probably the most important factor and it's definitely something you can't know until your surgery is done. 10mm margins are considered 'ideal' but very rarely seen; anything less than 2mm (sometimes 3mm, depending on the surgeon) usually requires a re-excision.  Surgeons try to deliver acceptable margins based on the area of DCIS that they see on the films but DCIS cancer cells are microscopic so it's pretty much impossible for a surgeon to guarantee margins of any size. 

- your age; younger women tend to have more aggressive cancers 

As you can see, most of these factors are things that you won't know until after surgery.  So while you can prepare for different scenerios, you really won't know how strongly radiation will be recommended, and what your benefit from radiation will be, until after you have surgery.

Off to see what studies I can find for you.