Luminal A or Luminal B

shlee

Hi ladies,

I have been doing a lot of reading in Dr. Love's breast book and she mentions several times the emerging importance of Luminal A and Luminal B classification in ER/PR positive cancers. Has anyone been told which type they are or has it not translated into treatment yet? Just wondering! Thanks!

SpecialK

Here is a chart that explains the subtypes:

Subtype	These tumors tend to be*	Prevalence (approximate)
Luminal A	ER+ and/or PR+, HER2-, low Ki67	40%
Luminal B	ER+ and/or PR+, HER2+ (or HER2- with high Ki67)	20%
Triple negative/basal-like	ER-, PR-, HER2-, cytokeratin 5/6 + and/or HER1+	15-20%
HER2 type	ER-, PR-, HER2+	10-15%
*These are the most common profiles for each subtype. However, not all tumors within each subtype will have all these features.

SpecialK

Sorry - had to delete the above post because the table I pasted was all sorts of weird!  Here is the info again:

Luminal A - ER+ and/or PR+, Her2-, low Ki67 - account for about 40% of breast cancers

Luminal B - ER+ and or PR+, Her2+ (or Her2-), high Ki67 - account for about 20% of breast cancers

Triple negative/basal like - ER-, PR-, Her2- , cytokeratin 5/6+, and/or Her1+ - account for 15-20% of BC

Her2 type - ER-, PR-, Her2+ - account for 10-15% of breast cancers

These are the most common profiles for each subtype, but not all tumors within each subtype will show  all of  these features.

Leah_S

I'm planning to talk to my onc about this at my next appt. I'll let you know what he says (assuming chemobrain lets me do that...).

Leah

SpecialK

I just finished participating in a clinical vaccine trial for Her2+ patients.  The trial was initially for Her2+++, but they have now widened the criteria to those expressing lower levels of Her2 positivity - those not given Herceptin during treatment because they were considered Her2-, so to extrapolate, the initial participants were Luminal B, but they would now potentially be including Luminal A patients in the trial, as there could be recurrence prevention benefit for them as well.

shlee

Hi ladies, thank you. I guess i am either luminal A or B... still waiting for the Ki67 back. thank you special k for the info... i was also i think just reading about your clinical trial and it sounds amazing. do you happen to know what it is called or how i could find out more about it? 

SpecialK

shlee - here is a link:

http://clinicaltrials.gov/show/NCT00524277 

I just flew back last night from Washington, D.C. from my last visit.  Don't have to go back for 6 months when I will get the booster.  I rationalized participation in this trial because it is single-blind and the placebo is a beneficial drug, much like Neulasta, and the cost far exceeds the airfare I paid to get there.  I lived in D.C. for 10 years when DH was stationed at the Pentagon so I had lots of friends to stay with and I had fun while there - also my DS lives there and I got to see him a lot, so it was good all the way around!  The trial was easy, very few SE from the injections, and great potential for benefit. I felt good about advancing the science for those ladies who will be dx'ed after me.  It was a pay it forward for those ladies who were in the trials for Herceptin, who helped bring that drug to the market for my benefit.

SelenaWolf

I am a Luminal A.  I was told by my oncologist when we first met to discuss my surgical pathology and how it would relate to my treatment protocol. 

LittleMelons

Here in Canada they don't seem to do the Ki67 or the Oncotype test on a routine basis and I have had neither. I asked for the Oncotype test and my Onc said it wouldn't change his treatment protocol (lumpectomy, raidation + Arimidex - no chemo), so wouldn't order it.  I know that I am 100% ER+ and 50% PR+.  How would I know if I am Luminal A or Luminal B? Or is it not possible to tell without the Ki67 test?

coraleliz

The Ki67 test wasn't done on either of my tumors. I'm assuming it was low because my occotype was low & that's apparently a big part of it.

SpecialK- I haven't read much about HER2+. Are they broadening the definiton or just broadening the participants thay include in the study. Some of us had "equivicol(sp)" results that went to FISH & were deemed negative. Thanks

SpecialK

littlemelons - if you have no access to your Ki67 info, you may be able to use your mitotic rate from your path report to guesstimate.  If your Ki67 was high it would seem to follow that you would have a fairly high mitotic rate as well.  If your mitotic rate was low you would probably fall into the Luminal A category.  I think most of Luminal B are true triple positives because approximately 25% of BC is Her2+.

coraleliz - they are not redifining Her2 positivity, they are broadening the enrollment criteria because they have discovered some evidence that this vaccine has an effect on patients with a lower Her2 expression as well as those of us who have the Her2+++ required for the enrollment previously.  The purpose is recurrence prevention so if it is of benefit to those who have a lower expression of Her2 they wanted to include that population as well.

coraleliz

SpecialK-thanks for the clarification. I haven't read much on HER2+ & this thread peaked my interest.

LittleMelons

Special K.  Thanks for the response.  I just checked my pathology report and the mitotic count is 1, which seems good.  However, the other two factors, tubule formation and nuclear pleomorphism, are 3 each, making me a high Grade 2, close to 3.  My Rad Onc called it a low risk cancer.  When I mentioned that to the breast specialist, he winced as if he disagreed and said "It's not screaming alarm, but it's not that good."  So I am wondering about the relative significance of the 3 factors making up our grade.  But maybe that is a separate topic.

I can't believe how knowledgable you ladies are on this site.  My docs tell me very little.