How do we know it is pure DCIS?

sunny----I think at some point you have to trust in your doctors. If you have already had bilat masts, amd 2 pathologists have said the nodes were negative, I think you have to realize that this is all good news, you've done everything you can to decrease your risk as much as possible, and it's now time to move on and enjoy your life. Praying for God's peace for you.

Anne

iHEARTu: if you still weigh the Tamoxifen route - just to let you know, DCIS may have different markers than its invasive part. My DCIS was variable ER+ (from low to high), but the microinvasion was not at all.

I also have periods of obsessing with uncertainty. Even worse is when oncos do not agree - my oncol did not recommend radiation but the radiation oncologist "offered" it anyway. Some do not treat micromets at all.

Wish you all more peace,
Jenna

After a diagnosis of breast cancer, it's impossible to not worry about the "what ifs?".  What's important, however, is to put the "what ifs?" into perspective.  So let me try to do that.

Is it possible that the pathologist missed a tiny microinvasion, hidden in the middle of the DCIS?  Yes, it is.  About 15% of women initially diagnosed with DCIS are subsequently found to have some invasive cancer, either a microinvasion or more.  I recall reading that about 10% of microinvasions are missed.  But what if it's more than this?  What if 20% of microinvasions are missed?  This would mean that 3% of women who think they have pure DCIS may in fact have a microinvasion that was not detected.  What if it's even more than that?  What if 10% of women who think they have pure DCIS in fact had an undetected microinvasion?

Is it possible that the nodes were checked but nodal involvement from this occult microinvasion was missed? Or that cancer cells escaped undetected through the bloodstream?  Yes it is.  It's estimated that this happens in 20% - 30% of cases where women with invasive cancer are found to be node negative. But this risk varies depending on the size of the invasive tumor; the risk is lower for smaller tumors and higher for larger tumors.  The size of the invasive tumor that we would be dealing with in situations like this, where the tumor wasn't even found by the pathologist, is in all likelihood only a microinvasion, i.e 1mm or smaller.  I don't know what the risk of undetected invasion would be for a tumor that small but I do know that chemo isn't offered to most women who have invasive tumors of less than 1cm, because of the low risk.  So for a tumor that is only 1mm in size, what might the risk of undetected invasion be?  5% at most?  Let's say 5%.  So in total, this means that 0.5% of women with DCIS might find themselves to be in this situation (5% of the 10% who had undetected microinvasions). 

Is it possible that in cases where a few random invasive breast cancer cells escaped into the body undetected, some of these cells might take hold and develop into mets?  Yes it is.  But in what percent of cases will this happen?  I don't know the answer to this, but I suspect that since we are talking about only a few cancer cells (as would likely be the case if the invasive cancer was not detected either in the breast or in the nodes), the percentage would be pretty low.  But let's be aggressive and assume that 20% of these missed invasions develop into mets.  So in total then we are talking about 0.1% of women who think they have "pure" DCIS who might be affected by this.

What this works out to is 10 women out of every 10,000 (I hope I did the math right!).  Of the approx. 50,000 cases of DCIS diagnosed every year in the U.S., 50 women might be affected.  Now of course I made up these numbers, but if anything I was overly aggressive.  The real risk is probably quite a bit lower.  And in any case, this is all just to provide perspective about the risk.

Before we were diagnosed with BC, we were each walking around with a breast cancer risk in the range of 10% to maybe 25%, depending on the individual (not including those who are BRCA+).  Yet most of us didn't worry about breast cancer all the time.  The risk that someone diagnosed with DCIS might have had an occult invasion that eventually will lead to mets is 0.1%.  We face greater risks simply by leaving the house every day... which of course isn't to scare anyone into staying inside all the time! 

Thanks everyone!   I'm a research geek, so I actually enjoy digging around the internet, trying to find answers to the mystery that is DCIS (and DCIS with microinvasions).  I remember the information that helped me understand my diagnosis, that armed me with questions for my doctors and helped me better understand what my doctors were saying.  And I remember the types of information that I found reassuring, during those times when panic would strike.  So really, all I do is share what I've learned in the course of my investigations about my own situation.  I'm glad that the info I provide is sometimes helpful to others.

I was diagnosed with DCIS on my left side in May '08 following slight blood discharge from that nipple for a few months which I didn't think was anything. I had been running on the treadmill for several months and just thought I had chaffed my nipple. Well, being a mom of three boys and working full time, we ladies sometimes procrastinate on monitoring our own health needs. I had a mastectomy with no radiation or chemo because I go just enough votes to have it diagnosed as cancer (DCIS) by the medical doctors but my ducts were visibly messed up based on what I saw on my mammo and subsequent MRI.

Fast forward to Nov 2009. I met with a mom friend who told me how her mom had a mastectomy (maybe double) and was cancer free for 18 years. Her mom did not do chemo or radiation but managed through holistic avenues. She was retired and subbing at a middle school when a kid pulled out her chair as a prank. Her hip began bothering her and she let it go for a month or so. I can't recall if she said she broke her hip or not. Anyway, her cancer reappeared in her injured hip. I had not heard of anything like that before but, of course, often you really don't learn much about a disease unless it affects you or someone close to you.

Fast forward to January of this year. I finally had been released from my plastic surgeon and was starting to feel my old self again. I was hanging some blinds on this window in our front entry. We have a two story house so I went up and down this extension ladder all day long that day. I was doing some touch-up paint, too. Soon after, my right hip started hurting. I chalked it up to middle age (48) and lack of exercise because I had to lay off during my three rounds of surgery and 2-3 tatoo procedures during the reconstruction phase because I couldn't sweat.

I had a long overdue well check in Feb because that slid on my priority list after dealing with a lot medically the last couple of years. I talked to my GP and asked him about my hip. He said based on what I described it was probably musce/tendon related. I thought it might be bursitis which I had 15+ years due to a bad exercise bike.

Now, we're here in mid-April and I've had the same consistent pain in my right hip -- no difference from Jan. I decided to call my plastic surgeon because she is just super in so many ways and I respect her medical knowledge immensely. I spoke with her assistant first saying -- "I'm probably being paranoid here but I had this friend whose mom..." My dr called me and said she'd seen about three cases with advanced stage of breast cancer that had metastised to the hip. She said my risk was extremely low but that I should probably check it out with an oncologist for peace of mind. I go next Friday and am to bring all of my pathology reports. I was not referred to an oncologist when I was first diagnosed by another surgeon. Hopefully, Beesie is right on with her statistics as my risk should be low but it's disconcerting to have to even slightly consider that something more serious might be wrong. Keep in mind I discounted my nipple discharge for several months before checking it out. It was comforting to read Beesie's stats so I'm going to try and think positive :-)

Beesie -- Thank you for your kind words of encouragement. Logically, I agree with you. Emotionally, it's another story. Ironically, I don't get emotional like this typically. I hope it does all chalk up to "old age." I'd take that any day over the alternative. Again, hoping I'm just being paranoid but, once you go through any cancer at any stage, you do get a bit hypersensitive when it comes to your health. Well, I'm not sure how much more I'll know Friday but, as we all know, it' a process of elimination to know what you're dealing with. Will post once I know more. Thank you and God bless.