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Topic: Chemo benefit (%) based on your Oncotype DX score

Forum: ILC (Invasive Lobular Carcinoma) — Just diagnosed, in treatment, or finished treatment for ILC.

Posted on: Dec 6, 2019 07:16PM

MikaMika wrote:

Hello, just got my results from the Oncotype DX test. Score =11, chemo benefit <1%. Could you please share your results and your decision with chemotherapy for ILC? I'm 38 y.o., had BMX on Halloween. My oncologist told me no chemo, but he willing to give me 4 rounds of Taxotere (maybe I'm wrong with the drug name) just to be sure we did everything.

What was your decision based on the test results?

Dx at 38 Dx 8/2019, ILC, Stage IIA, Grade 2, ER+/PR+, HER2- Radiation Therapy Hormonal Therapy Arimidex (anastrozole)
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Dec 6, 2019 10:49PM OnTarget wrote:

My score was 16. The printout said my risk of recurrence was 4% and chemo benefit was <1%.

But then the latest TAILORx results (which are the basis of the Oncotype % in the low and intermediate ranges) came out. Adding my age and clinical risk, my new stats were ~12% risk of distance recurrence in 9 yrs, and an absolute chemo benefit of ~6%.

I also asked my MO to do my RSPC score and it said 13% chance of recurrence.

All of that added up to more risk than I wanted, so I did 4 rounds of TC. I'm happy that I did everything I could.

Diagnosed at 42, Oncotype score 16, ITC in one node- considered node negative. Lost right implant to infection March 2020. Waiting to start reconstruction all over again. Dx 4/8/2019, ILC, Left, 3cm, Stage IB, Grade 2, 0/3 nodes, ER+/PR+, HER2- Dx 4/23/2019, ILC, Right, <1cm, Stage IA, Grade 2, 0/2 nodes, ER+/PR+, HER2- Surgery 5/15/2019 Lymph node removal: Sentinel; Mastectomy: Left, Right; Reconstruction (left): Tissue expander placement; Reconstruction (right): Tissue expander placement Hormonal Therapy 6/13/2019 Zoladex (goserelin) Chemotherapy 8/5/2019 Cytoxan (cyclophosphamide), Taxotere (docetaxel) Surgery 11/5/2019 Reconstruction (left): Silicone implant; Reconstruction (right): Silicone implant
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Dec 7, 2019 10:00AM Beesie wrote:

MikaMika, I don't have ILC but I saw your post and OnTarget's reply, and want to reinforce something she said.

You haven't posted any information about your diagnosis but you did state your age. Age is one factor in risk recurrence. So I would suggest that you ask your Oncologist to run the RSPC model for you. This is a computer model that the Oncotype people make available to Oncologists. It's long name is "Recurrence Score Pathology Clinical" and what it does is take your score (11), and add in your age (38), the tumor size (?) and the tumor grade (?), and whether you will be taking Tamoxifen or an AI, and it kicks out a new metastatic recurrence risk (and therefore, chemo benefit) that is more specific to you personally.

For someone with a high score who is older or has a very small lower grade tumor, the model might show a significantly lower risk that the generic results that are associated with each recurrence score. Alternately, for someone with a low score who is younger or who has a large high grade tumor, the model might show a significantly higher risk than the generic report.

Since you aren't sure what to do based on your Oncotype result, this additional information might be helpful. I would assume your MO has access to the RSPC model - I think all MOs do, although I'm not sure. It's a quick computer model - it provides the result as soon as the MO inputs the information.

Good luck with your decision.

“No power so effectually robs the mind of all its powers of acting and reasoning as fear.” Edmund Burke
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Dec 7, 2019 10:48AM MikaMika wrote:

Thank you so much for your replies! I will go for second opinion and also ask to run RSPC model.

Dx at 38 Dx 8/2019, ILC, Stage IIA, Grade 2, ER+/PR+, HER2- Radiation Therapy Hormonal Therapy Arimidex (anastrozole)
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Dec 7, 2019 10:57AM MikaMika wrote:

OnTarget,

Thank you so much for helping me. I tried to find the link to TailorX results to see the new statistics for my age. If it is possible could you please share the link?

Dx at 38 Dx 8/2019, ILC, Stage IIA, Grade 2, ER+/PR+, HER2- Radiation Therapy Hormonal Therapy Arimidex (anastrozole)
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Dec 7, 2019 10:59AM MikaMika wrote:

Beesie,

Thank you so much for your explanation!

Dx at 38 Dx 8/2019, ILC, Stage IIA, Grade 2, ER+/PR+, HER2- Radiation Therapy Hormonal Therapy Arimidex (anastrozole)
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Dec 7, 2019 03:08PM - edited Dec 7, 2019 03:08PM by ShetlandPony

Further analysis of TAILORx:


Clinical and Genomic Risk to Guide the Use of Adjuvant Therapy for Breast Cancer

June 20, 2019
N Engl J Med 2019; 380:2395-2405
DOI: 10.1056/NEJMoa1904819

https://www.nejm.org/doi/full/10.1056/NEJMoa1904819

2011 Stage I ILC 1.5cm grade1 ITCs sn Lumpectomy,radiation,tamoxifen. 2014 Stage IV ILC mets breast,liver. TaxolNEAD. Ibrance+letrozole 2yrs. Fas+afinitor nope. XelodaNEAD 2yrs. Eribulin,Doxil nope. SUMMIT FaslodexHerceptinNeratinib for Her2mut NEAD
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Dec 7, 2019 03:15PM ShetlandPony wrote:

How much we should trust Oncotype for ILC is another question. See the threads here about LobSig.

2011 Stage I ILC 1.5cm grade1 ITCs sn Lumpectomy,radiation,tamoxifen. 2014 Stage IV ILC mets breast,liver. TaxolNEAD. Ibrance+letrozole 2yrs. Fas+afinitor nope. XelodaNEAD 2yrs. Eribulin,Doxil nope. SUMMIT FaslodexHerceptinNeratinib for Her2mut NEAD
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Dec 7, 2019 05:44PM MikaMika wrote:

I read articles about LobSig. But as I understand, this test is not available now for patients.

Dx at 38 Dx 8/2019, ILC, Stage IIA, Grade 2, ER+/PR+, HER2- Radiation Therapy Hormonal Therapy Arimidex (anastrozole)
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Dec 7, 2019 07:40PM OnTarget wrote:

LobSig looks good, but one thing I note is that 5 people died within 8 years who were considered low risk. Four of those were considered high risk by Oncotype testing, and the fifth was considered low risk by both.

I think LobSig could mean that far less people are overtreated, but 4 would have died potentially from being undertreated versus with Oncotype.

https://www.nature.com/articles/s41523-019-0113-y

It will be exciting to see how this develops and is refined over time.


Diagnosed at 42, Oncotype score 16, ITC in one node- considered node negative. Lost right implant to infection March 2020. Waiting to start reconstruction all over again. Dx 4/8/2019, ILC, Left, 3cm, Stage IB, Grade 2, 0/3 nodes, ER+/PR+, HER2- Dx 4/23/2019, ILC, Right, <1cm, Stage IA, Grade 2, 0/2 nodes, ER+/PR+, HER2- Surgery 5/15/2019 Lymph node removal: Sentinel; Mastectomy: Left, Right; Reconstruction (left): Tissue expander placement; Reconstruction (right): Tissue expander placement Hormonal Therapy 6/13/2019 Zoladex (goserelin) Chemotherapy 8/5/2019 Cytoxan (cyclophosphamide), Taxotere (docetaxel) Surgery 11/5/2019 Reconstruction (left): Silicone implant; Reconstruction (right): Silicone implant
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Dec 7, 2019 08:14PM MikaMika wrote:

OnTarget,

Thank you so much!

Dx at 38 Dx 8/2019, ILC, Stage IIA, Grade 2, ER+/PR+, HER2- Radiation Therapy Hormonal Therapy Arimidex (anastrozole)
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Dec 7, 2019 09:34PM - edited Dec 7, 2019 09:36PM by ShetlandPony

Yes, LobSig is not available, and may need more work. My point in mentioning it, and this is just my opinion, is that since Oncotype has been validated mostly with women who had IDC, perhaps we should pay particular attention to clinical features and age, and err on the side of caution, in cases of ILC.

2011 Stage I ILC 1.5cm grade1 ITCs sn Lumpectomy,radiation,tamoxifen. 2014 Stage IV ILC mets breast,liver. TaxolNEAD. Ibrance+letrozole 2yrs. Fas+afinitor nope. XelodaNEAD 2yrs. Eribulin,Doxil nope. SUMMIT FaslodexHerceptinNeratinib for Her2mut NEAD
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Dec 7, 2019 09:47PM MikaMika wrote:

Thank you so much for your response!

But how can we know which treatment works for ILC? I heard a lot that chemo doesn't work well on ILC, and AI is preferable.

Dx at 38 Dx 8/2019, ILC, Stage IIA, Grade 2, ER+/PR+, HER2- Radiation Therapy Hormonal Therapy Arimidex (anastrozole)
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Dec 7, 2019 10:02PM - edited Dec 7, 2019 10:07PM by ShetlandPony

I think the source of that idea is a study that showed not as many compete pathological responses to chemo in ILC compared to IDC. But that does not mean no response. In addition, it is apparent that advanced ILC often does respond to chemo. To further complicate matters, there is the idea that some or all of chemo's benefit for younger women with ER+ Her2- bc could be that it suppresses ovulation (chemopause), and not the cytotoxic effects per se. Another thing to consider is that we have data that seem to show at least a subset of ILC may be de novo resistant to tamoxifen, whereas the aromatase inhibitors are more effective. I will refer you to the web site of the Lobular Breast Cancer Alliance where you can read articles and see a list of medical journal articles. Lobularbreastcancer.org

If you were to do ovarian suppression plus an aromatase inhibitor, that would be considered more aggressive than just tamoxifen, and less aggressive than chemo. Keep asking questions, make your oncologist work hard, and come up with a plan that is tailored specifically for you.

2011 Stage I ILC 1.5cm grade1 ITCs sn Lumpectomy,radiation,tamoxifen. 2014 Stage IV ILC mets breast,liver. TaxolNEAD. Ibrance+letrozole 2yrs. Fas+afinitor nope. XelodaNEAD 2yrs. Eribulin,Doxil nope. SUMMIT FaslodexHerceptinNeratinib for Her2mut NEAD
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Dec 7, 2019 10:33PM MikaMika wrote:

Thank you so much!

I'm so grateful for your support!

Dx at 38 Dx 8/2019, ILC, Stage IIA, Grade 2, ER+/PR+, HER2- Radiation Therapy Hormonal Therapy Arimidex (anastrozole)
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Dec 7, 2019 10:57PM - edited Dec 8, 2019 12:32AM by JRNJ

MikaMika, You didn't say anything about your node status or lymphovascular invasion. I'm guessing it's negative because your report had an actual quantification on it. The node positive reports do not report a number because the studies are still ongoing so they just say "no apparent benefit". I'm Oncotype 15, 54, pre-menopausal, pleomorphic ILC, with lymphovascular invasion and extra-nodal extension, 2 positive nodes, 3 mm and 2mm, Ki%=18. Although Oncotype says "no apparent benefit", this all added up to chemo in my mind. I had one dr. say I don't know, one say definitely NO chemo (she is involved in Oncotype studies and said I have a low miotic score). I was uncomfortable with this so went to Sloan for another opinion and they said definitely YES to chemo (due to ongoing studies not yet finished and my other features described above). How could 2 drs. have such different polar opposite opinions? To be honest, I totally respect the dr. that said I was in the gray area and I don't really know, because you can't be sure. I started chemo on Monday. Sloan also seems to really like CMF for "lower risk" people. Our CMF string is mostly recommendations from Sloan. That being said, if you are node negative and Oncotype 11, it's another tough one. I don't know how children factor into the equation. If you want to have children, maybe you don't want ovarian suppression.

Thanks OnTarget and Shetland Pony for your help in my decision process!!!

Pleomorphic Multifocal, Extra nodal Extension, Lymphovascular Invasion. TEs removed due to infection Dx 8/15/2019, LCIS, Right, 6cm+, Grade 3, ER+/PR+, HER2- Dx 8/15/2019, ILC, Right, 2cm, Grade 3, 2/5 nodes, ER+/PR+, HER2- Surgery 9/24/2019 Lymph node removal: Sentinel; Mastectomy: Right; Prophylactic mastectomy: Left; Reconstruction (left): Tissue expander placement; Reconstruction (right): Tissue expander placement Chemotherapy 12/2/2019 CMF Radiation Therapy 3/30/2020 Whole-breast: Breast, Lymph nodes, Chest wall Hormonal Therapy 6/4/2020 Aromasin (exemestane) Hormonal Therapy 8/6/2020 Arimidex (anastrozole) Surgery 8/25/2020 Prophylactic ovary removal
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Dec 8, 2019 01:47AM - edited Dec 8, 2019 01:51AM by ShetlandPony

Ovarian suppression with Lupron would be temporary, not permanent as it would be with oophorectomy.

JRNJ, fwiw your choice seems reasonable to me!

Best wishes, MikaMika. Please keep us posted on what you and your onc decide.

2011 Stage I ILC 1.5cm grade1 ITCs sn Lumpectomy,radiation,tamoxifen. 2014 Stage IV ILC mets breast,liver. TaxolNEAD. Ibrance+letrozole 2yrs. Fas+afinitor nope. XelodaNEAD 2yrs. Eribulin,Doxil nope. SUMMIT FaslodexHerceptinNeratinib for Her2mut NEAD
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Dec 8, 2019 02:41AM - edited Dec 8, 2019 02:58AM by MikaMika

Thank you so much for the information.

I'm sorry, I can't add my info permanently. It seems like I have sort of mental block.

I have BRCA 2 mutation.

I had removed 1 node and it contained rare ITC.

Pathologists didn't find extranodal extension or lymphovascular invasion. Since I had multifocal ILC (with greatest tumor 2.2 cm) and because of my node, I was suggested to do radiation treatment (even though I had BMX). And after that start AI +ovarian suppression for now, later going through oophorectomy.


I want to have children. I don't have them. But how?

We were working on that before I was diagnosed.

My oncologist is considered to be the most "aggressive" one in our area. But he is Ok with skipping chemo, and he is not Ok with any children plans. From the very beginning his point was 10 years on AI.


Dx at 38 Dx 8/2019, ILC, Stage IIA, Grade 2, ER+/PR+, HER2- Radiation Therapy Hormonal Therapy Arimidex (anastrozole)
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Dec 8, 2019 02:55AM MikaMika wrote:

It seems like my oncologist doesn't like CMF regime. The lightest one that he suggested was 4xTC.

I'll see what other doctors think.

Dx at 38 Dx 8/2019, ILC, Stage IIA, Grade 2, ER+/PR+, HER2- Radiation Therapy Hormonal Therapy Arimidex (anastrozole)
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Dec 8, 2019 02:44PM wallycat wrote:

When I lived in WI and first dx, my then second oncologist (fired the first) also stated what ShetlandPony said: Most of the european countries that opt to give patients chemo and have better outcomes is due to the ovarian suppression from the protocol (he is British).

Dx 4/07 1 month before turning 50; ILC 1.8cm, ER+/PR+, HER2 neg., Stage 1, Grade 2, 0/5 nodes. Onco score 20, Bilateral Mast., tamoxifen 3-1/2 years, arimidex-completed 4/20/2012
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Dec 8, 2019 04:43PM MikaMika wrote:

I heard that, too.

I also tried to find the results of trials, when women with ILC got AI before their surgeries to shrink tumors.

Dx at 38 Dx 8/2019, ILC, Stage IIA, Grade 2, ER+/PR+, HER2- Radiation Therapy Hormonal Therapy Arimidex (anastrozole)
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Dec 8, 2019 11:11PM JRNJ wrote:

MikaMika, The decisions in this process are so hard. I'm sorry you also have to factor in children. I had mine late, 39 and 41, no problem getting pregnant (overly hormonal, I thought it was a good thing.....) If it is important to you, than maybe get another opinion. Maybe chemo and radiation, break to have children, than AI? Or freeze eggs and get a surrogate? I struggled with getting another opinion until the time was right. When I didn't like what I was hearing it was time, and my MO was very supportive. I got two additional opinions. It was my BS that I hated. That support prompted me to go back to him. I'm not surprised yours doesn't like CMF. It appears to be a Sloan and CA thing. Everyone else is doing TC. I have some worries about that, but decided to trust the Sloan recommendation as they are #2 in the country. The risks for permanent side effects are lower with CMF. And supposedly I won't lose all my hair, yay!

Pleomorphic Multifocal, Extra nodal Extension, Lymphovascular Invasion. TEs removed due to infection Dx 8/15/2019, LCIS, Right, 6cm+, Grade 3, ER+/PR+, HER2- Dx 8/15/2019, ILC, Right, 2cm, Grade 3, 2/5 nodes, ER+/PR+, HER2- Surgery 9/24/2019 Lymph node removal: Sentinel; Mastectomy: Right; Prophylactic mastectomy: Left; Reconstruction (left): Tissue expander placement; Reconstruction (right): Tissue expander placement Chemotherapy 12/2/2019 CMF Radiation Therapy 3/30/2020 Whole-breast: Breast, Lymph nodes, Chest wall Hormonal Therapy 6/4/2020 Aromasin (exemestane) Hormonal Therapy 8/6/2020 Arimidex (anastrozole) Surgery 8/25/2020 Prophylactic ovary removal
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Dec 8, 2019 11:37PM MikaMika wrote:

JRNJ,

Thank you so much for your support!

Yes, I'm going to ask for the second opinion.

And I believe you got your chemo advice from the very trusted source. How are you doing on this regime?


Dx at 38 Dx 8/2019, ILC, Stage IIA, Grade 2, ER+/PR+, HER2- Radiation Therapy Hormonal Therapy Arimidex (anastrozole)
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Dec 8, 2019 11:48PM JRNJ wrote:

I started Monday. I just posted the details at: CMF treatment survivors and experiences. The brief summary is, I had a few pretty crappy days this week, but feel pretty good today, day 7. I've been shopping all day. I'm prone to nausea and thought for sure I'd be really nauseous. But I wasn't. I think they overmedicated me and my worst side effect was medication withdrawal and insomnia.


Pleomorphic Multifocal, Extra nodal Extension, Lymphovascular Invasion. TEs removed due to infection Dx 8/15/2019, LCIS, Right, 6cm+, Grade 3, ER+/PR+, HER2- Dx 8/15/2019, ILC, Right, 2cm, Grade 3, 2/5 nodes, ER+/PR+, HER2- Surgery 9/24/2019 Lymph node removal: Sentinel; Mastectomy: Right; Prophylactic mastectomy: Left; Reconstruction (left): Tissue expander placement; Reconstruction (right): Tissue expander placement Chemotherapy 12/2/2019 CMF Radiation Therapy 3/30/2020 Whole-breast: Breast, Lymph nodes, Chest wall Hormonal Therapy 6/4/2020 Aromasin (exemestane) Hormonal Therapy 8/6/2020 Arimidex (anastrozole) Surgery 8/25/2020 Prophylactic ovary removal
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Dec 9, 2019 12:54AM MikaMika wrote:

JRNJ,

It's great to hear that you are doing well! I wish you to go through this treatment with minimal side effects!

Dx at 38 Dx 8/2019, ILC, Stage IIA, Grade 2, ER+/PR+, HER2- Radiation Therapy Hormonal Therapy Arimidex (anastrozole)
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Dec 17, 2019 12:25AM Dreamer1 wrote:

Hi, Mika, I just got my Oncotype test results today, it was 10. Neither of the 2 med oncs are recommending chemo. I am 59 and had my kids. I agree with other posters - get a second opinion on any matters that are in your personal "gray" decision making zone. I saw 3 surgeons, they all said different things. The 2 med oncs are not differing on chemo, but they have diff preferences for which AI to start me on.

Oncotype = 10 Dx 10/15/2019, IDC, Left, 1cm, Stage IA, Grade 1, 0/5 nodes, ER+/PR+, HER2- (IHC) Dx 10/31/2019, DCIS, Left, 4cm, Stage 0, Grade 2, 0/5 nodes, ER+/PR+, HER2- (IHC) Surgery 11/20/2019 Lumpectomy: Left; Lymph node removal: Sentinel Radiation Therapy 1/2/2020 Whole-breast: Breast Hormonal Therapy 2/9/2020 Arimidex (anastrozole)
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Dec 17, 2019 12:40AM - edited Dec 17, 2019 12:40AM by thisiknow

Dreamer1 ...I'd be interested to know what the different preferences of AI's are by your different MO's. We have similar dx profiles.

Age 72 @dx - Oncotype 4 & 15 Dx 7/14/2019, DCIS/IDC, Both breasts, 1cm, Stage IA, Grade 1, 0/3 nodes, ER+/PR+, HER2- (FISH) Surgery 9/10/2019 Lumpectomy: Left, Right; Lymph node removal: Sentinel Radiation Therapy 10/28/2019 Whole-breast: Breast Hormonal Therapy 12/18/2019 Arimidex (anastrozole)
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Dec 17, 2019 05:57AM - edited Dec 17, 2019 06:07AM by JRNJ

Dreamer Me to regarding info on different ais

Mika thanks! Not the worst case scenario but still not up for working for going out the first week much and can’t even relax in bed due to jitters and insomnia so still sucks. Second week was fine.



Pleomorphic Multifocal, Extra nodal Extension, Lymphovascular Invasion. TEs removed due to infection Dx 8/15/2019, LCIS, Right, 6cm+, Grade 3, ER+/PR+, HER2- Dx 8/15/2019, ILC, Right, 2cm, Grade 3, 2/5 nodes, ER+/PR+, HER2- Surgery 9/24/2019 Lymph node removal: Sentinel; Mastectomy: Right; Prophylactic mastectomy: Left; Reconstruction (left): Tissue expander placement; Reconstruction (right): Tissue expander placement Chemotherapy 12/2/2019 CMF Radiation Therapy 3/30/2020 Whole-breast: Breast, Lymph nodes, Chest wall Hormonal Therapy 6/4/2020 Aromasin (exemestane) Hormonal Therapy 8/6/2020 Arimidex (anastrozole) Surgery 8/25/2020 Prophylactic ovary removal
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Dec 17, 2019 11:29AM MikaMika wrote:

I'm also interested in research about AI. Which one is better or has less side effects?

Dx at 38 Dx 8/2019, ILC, Stage IIA, Grade 2, ER+/PR+, HER2- Radiation Therapy Hormonal Therapy Arimidex (anastrozole)
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Dec 17, 2019 01:07PM Beesie wrote:

Mika,

From the standpoint of tolerance, which is best depends on the person taking it.

If you read the board, you'll find that there are people who started with Letrozole (Femara or generic) or with Anastrozole (Arimidex or generic) or with Exemestane (Aromasin or generic) and did well. Then there are others who started with any of the three, had quality of life side effects, switched to one of the others and did well. There are some people will tolerate any of the AIs well, and other people who will have trouble tolerating any of them.

For those for take the generic versions, sometimes one brand of generic is more tolerable than another brand of generic, for the very same drug.

From the standpoint of side effects, again it depends very much on the individual, but here is a comparison from BCO:

https://www.breastcancer.org/treatment/hormonal/comp_chart


And here are comparisons of Anastrozole vs. Letrozole, and one of Aromasin vs. Anastrozole .


From the standpoint of effectiveness and toxicity, the results seem to vary depending on the study. Generally all 3 AIs perform about the same.

Here are a number of studies that have compared the effectiveness of the AIs:

Adjuvant anastrozole versus exemestane versus letrozole, upfront or after 2 years of tamoxifen, in endocrine-sensitive breast cancer (FATA-GIM3): a randomised, phase 3 trial (2018)

  • "5-year disease-free survival was 90·0% (95% CI 87·9–91·7) with anastrozole (124 events), 88·0% (85·8–89·9) with exemestane (148 events), and 89·4% (87·3 to 91·1) with letrozole (129 events; p=0·24). No unexpected serious adverse reactions or treatment-related deaths occurred."

.

Do all aromatase inhibitors have similar efficacy and safety? (2017)

  • "Letrozole is a more potent inhibitor of aromatase than anastrozole at their conventionally used doses, and leads to more complete inhibition of whole-body aromatase. Geisler et al. reported that mean percentage aromatase inhibition with anastrozole was 97.1%, whereas more than 99.1% suppression of aromatase enzyme was observed with letrozole in standard treatment doses"
  • "In a randomized Phase III MA.27 trial (NCT00066573), the efficacy of steroidal aromatase inhibitor exemestane and nonsteroidal aromatase inhibitor anastrozole for 5 years in the adjuvant hormonal treatment of hormone receptor-positive postmenopausal early breast cancer was compared [7]. Total of 7576 patients were enrolled in this first comparison of steroidal and nonsteroidal classes of aromatase inhibitors trial, and the primary outcome 4-year event-free survival (EFS) rates were similar: 91% for exemestane and 91.2% for anastrozole in the initial adjuvant therapy of hormone receptor-positive breast cancer with a median 4.1-year follow-up (HR: 1.02; 95% CI: 0.87–1.18; p = 0.85). In a recent published randomized Phase III Femara Versus Anastrozole Clinical Evaluation (FACE) trial (NCT00248170), Smith et al. compared the efficacy and safety of adjuvant letrozole and anastrozole in postmenopausal patients with hormone receptor and node-positive early breast cancer [8]. A total of 4136 patients were randomized and 5-year estimated disease-free survival (DFS) rates were 84.9 and 82.9% for letrozole and anastrozole arms, respectively (HR: 0.93; 95% CI: 0.80–1.07; p = 0.31)."

.

No Efficacy Difference Between Adjuvant Letrozole and Anastrozole in Postmenopausal Women With Early Breast Cancer (2017)

  • "The 5-year estimated disease-free survival rate was 84.9% in the letrozole group vs 82.9% in the anastrozole group.....The 5-year estimated overall survival rate was 89.9% vs 89.2%"
  • "The most common adverse events of any grade in the letrozole vs anastrozole groups were arthralgia (48% vs 48%), hot flushes (33% vs 32%), fatigue (17% vs 17%), osteoporosis (11% vs 11%), myalgia (11% vs 10%), and back pain (10% vs 9%). The most common grade 3 or 4 adverse events were arthralgia (3.9% vs 3.3%), hypertension (1.2% vs 1.0%), hot flushes (0.8% vs 0.4%), myalgia (0.8% vs 0.7%), dyspnea (0.8% vs 0.5%), and depression (0.8% vs 0.6%)."
  • "Adverse events led to discontinuation of treatment in 15.1% vs 14.3% of patients and dose interruption or reduction in 8.2% vs 7.7%. Serious adverse events considered related to treatment occurred in 2.6% vs 2.3%. Death occurred in 2.0% vs 2.2% of patients; causes other than disease progression included cardiac failure (six vs two patients), pulmonary embolism (two vs four patients), and chronic obstructive pulmonary disease (one vs four patients)."

.

Differences between the non-steroidal aromatase inhibitors anastrozole and letrozole – of clinical importance? (2011)

  • "In addition to being the most potent non-steroidal AI, letrozole is the only AI that has demonstrated superior efficacy in both the neoadjuvant and adjuvant settings compared with tamoxifen. A significant reduction of early DM in the adjuvant setting has been shown with letrozole, and a survival benefit is emerging with longer follow-up in the BIG 1–98 trial. In contrast, 100-month survival data from the ATAC trial do not demonstrate an OS benefit for anastrozole vs tamoxifen."

.

What it comes down to is that different MOs have different preferences, possibly depending on which study they read last or which study sticks in their mind most. There is really nothing out there that says that one is any better than the others, or that one will be more easily tolerated. It's all a question of how your body reacts to one vs. another.

“No power so effectually robs the mind of all its powers of acting and reasoning as fear.” Edmund Burke
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Dec 17, 2019 01:44PM MikaMika wrote:

Beesie,

Thank you so much for your response and help!

Dx at 38 Dx 8/2019, ILC, Stage IIA, Grade 2, ER+/PR+, HER2- Radiation Therapy Hormonal Therapy Arimidex (anastrozole)

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