LCIS response to CHEMO

hopeandfuture72

I was diagnosed with 1.2 cm ILC with LCIS originally. The day before schedueled lumpectomy I had an MRI. BS called me that night and said I had a large (5 cm) non-mass close to the muscle. She recommended neoad. chemo to shrink back the non-mass. This was before it was biopsied. I had the biopsy the next day and it was originally diagnosed as DCIS. My BS and the oncologist read the MRI report in a way that did not seem correct to me. I asked for a second opinion and I was correct. The Dr. wrote an addendum to the MRI to clarify that the non-mass was NOT in the muscle. They still wanted to do chemo even though I questioned them since I knew DCIS was not treated with chemo. I had 3 rounds of dose-dense AC. I was still not feeling great about this treatment plan. I went to another cancer treatment center to get a second opinion. They re-read the MRI and confirmed again that it was NOT in the muscle. They also re-diagnosed the DCIS as LCIS! They said no more chemo (I was still supposed to do 4 rounds of T based on first oncologist's treatment plan)

So after months of questions and uncertainty, this is what I was confirmed to have...

1.2 cm ILC with LCIS ER/PR +, HER2 -, Magee score 11, intermediate grade/2

5 cm LCIS

HERE IS MY QUESTION? I had 4 rounds of AC. I had an MRI 9 days after the last chemo treatment. My BS called me and said it is ALL gone. No signs of either area. I was happy beyond belief. She said she was not expecting that and was very surprised to see LCIS respond so quickly and completely to chemo. Because LCIS is not treated with chemo, she can't check studies etc. Has anyone ever heard of LCIS respond completely to chemo if for some reason a patient was given chemo for another reason?

MelissaDallas

Hope, why don't you "copy & paste" your question to the ILC or IDC forums? Since none of us with "LCIS only" have had chemo for breast cancer I'm not sure anyone here can answer your question, but it isn't unusual for there to be an "alphabet soup" of atypical or in situ findings along with invasive cancer. It is a really interesting question & I'd be curious to see what answers you get. I didn't need chemo for my ovarian cancer, so I'm no help

leaf

I don't understand how your oncologist can say FOR SURE that ALL your LCIS is gone. LCIS is not RELIABLY detected by any imaging means or by palpation. LCIS is often multifocal (meaning there are several spots of it in a breast), and often bilateral. It is only reliably diagnosed by taking a sample of tissue and looking at it under the microscope. So even if all your known LCIS spot(s) were removed with clean margins, you could still have a foci somewhere else in that or the other breast.

While it is thought that SOME LCIS may itself turn into invasive cancer (because clonally SOMETIMES the LCIS resembles a local invasive cancer), sometimes LCIS women get an invasive breast cancer that does NOT resemble their LCIS. LCIS could be a marker for some unknown mechanism that increases one's risk for breast cancer.

For many LCIS women who subsequently get invasive breast cancer, the invasive breast cancer occurs in an area that previously looked benign in imaging. Even when they biopsy LCIS-only women, the LCIS sometimes occurs not AT but NEXT TO the calcifications or other abnormality that prompted the biopsy.

So, even if your chemo killed all the LCIS (which I would somewhat question because probably at least some LCIS is slower growing than some invasive breast cancers, and I think most traditional chemos work on dividing cells), it would be very difficult to tell this without removing an LCIS foci post-chemo. I don't know if the pathologist can tell if LCIS is dividing or not. But they certainly couldn't be certain where all the LCIS was in your breast.