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Jeanne
05-18-2006, 09:54 AM
Hi,

This is my first post to the group. I was diagnosed with mixed ductal and lobular invasive BC in March 2006. I had a lumpectomy + sentinel node biopsy later in March and the nodes and margins were clean. The tumor is 1.2 cm and 80% ER+ and 90% PR+. (My internist is my hero for finding the lump at such an early stage!)

My HER2/neu score using the IHC test is 3+ on both the core biopsy and the excised tumor. Given my negative node status and the relatively small size of my tumor, my oncologist decided to have the FISH test done before proceeding with treatment. Strangely, the FISH test was negative (1.2). Does anyone have any experience with this? My oncologist is following up with the pathology folks who did both tests and they might do another FISH test to be sure.

My oncologist also had an ONCOTYPE DX test done. I got a score of 33, which is on the low end of the high scale (as my husband puts it). Based on this score, my chance of a distant recurrence in 10 years is 22%. Does anyone have any experience with this test? My oncologist feels that this is all the more reason to do chemo. (Some of her colleagues had thought I might be able to get away with endocrine therapy only.)

For what it's worth, I am 39 years old. My oncologist has preliminarily recommended 4 rounds of AC over 3 months followed by weekly Taxol + Herceptin for 3 months, then Herceptin only to finish out a full year, followed by endocrine therapy (Tamoxifen or similar). 6 weeks of radiation after the chemo. Alternatively, I probably qualify for a dose-dense clinical trial with the AC every 2 weeks and partial breast radiation for 3 weeks during the chemo rather than afterwards. My understanding is that the only issue on the table is whether to include Herceptin given my FISH- status, and I get to choose whether to take the dose dense approach (which does not affect my ability to get Taxol with or without Herceptin afterwards). At first I was very attracted to the dose dense alternative but I want to do whatever is going to be most effective. I would be interested in the group's thoughts on any or all of the above. Many thanks in advance for your help.

Jeanne

P.S. Shortly after my diagnosis, Cynthia posted a request on my behalf for information about early stage BC treatment for Her2+ folks. Thanks very much to all who responded and my apologies for not conveying my thanks before.

saleboat
05-18-2006, 10:08 AM
Jeanne,

The issue with the IHC tests is that they can provide a false-positive reading. The FISH test is more accurate, but it measures Her2 in a different way than IHC. (IHC measures Her2 on the outside of the cell, FISH measures on the inside of the cell) I would make sure that both tests are done by an experienced, high-volume lab-- if you're not at a major cancer center, you may want to send your slides to one, such as Dana Farber, Sloan-Kettering, etc.

There are a minority of women who are genuinely IHC + and FISH negative. I am one of them, and finishing my year of Herceptin in August. If anything, I would have the IHC retested, not the FISH, but then again, I'm not a pathologist.

I had dose dense A/C, followed by dose dense Taxol with Herceptin. You may want to talk about this option as well. Dose dense has been shown to be more effective with Her2+ breast cancer, but since the big Herceptin studies (for early stage breast cancer) were done using the traditional, three week chemo dosing schedule (dose dense is every two weeks) the side-effects on the heart are unknown. You may also want to get your TOPO tested-- if you search on this web-site, you'll find info on this tumor marker. This has been associated with heart damage when Adriamycin chemo is given-- it may be that a different chemo-- Carboplatnium, Taxol & Herceptin may provide a better risk profile.

Good luck with all of this,
Jen

Jeanne
05-18-2006, 10:17 AM
Thanks, Jen. I should have mentioned that I am at Johns Hopkins and have a superb team. Everything is vetted through their weekly multidisciplinary tumor board. I have been very, very happy with the quality of care.

saleboat
05-18-2006, 10:44 AM
Hi again Jeanne--

Sounds like you're in great hands. I've attached a publication on the different testing methods and response rates-- it is a bit dated (2002) but the information is still valid in terms of explaining the different tests and response rates.

http://www.labcorp.com/clinicaltrials/what/HER2.pdf

Of Her2 patients, there are a small percentage who are IHC + and FISH - and for whom Herceptin is still appropriate. (There are even a smaller number, I believe, who are IHC - and FISH +).

I hope this is helpful.

Jen