Just some Clarification Please...

It can also be listed on pathology  as MKI67.

My BS first mentioned it several months after my diagnosis when we were discussing the pros and cons of a double mastectomy. Mine was 19% (I think) which being at the top end of that bracket put me in a "grey area" as far as that indicator was concerned. He described it as "a poor man's oncotype test" and said many doctors don't factor it in any more. Your doctor may be one of those @kitkatb.

I'm not sure how accurate the Ki67 is as a measure...mine was less than 10% but my cancer was classed as pleomorphic and therefore fast growing (estimated to have only been growing for 12 months or possibly 2 years at most and was already 4.5cm and into 3 nodes).  That floored me when I found out.

@kitkatb
My Ki-67 was listed on my initial biopsy report but not on my final report. The percentage was high at 80%. My oncologist said that she regards the result as "numbers" in that it does not change treatment decisions or followup, it is a guide along with all else the medical team take into consideration.

I have a Ki-67 result on both my initial biopsy report and on the full report.  My breast surgeon said at my first appointment that the 70-80% from my initial biopsy was “significant”. The final 50% result from my lumpectomy is still frighteningly high but my oncologist assures me is very typical of TNBC.

I spent a lot of time worrying about a high Ki-67 and what it meant. Some things I read said a high Ki-67 meant a worse prognosis and others said a better chemo response.  In the end I think it’s just something that goes hand in hand with TNBC (like being Grade 3) and not something additional to worry about.

Thanks for that @"Annie C"   Explains things really well.   Is it something you actually ask for or is it something which is done depending on your type and grade of cancer.  

Wow @Mantis I never knew that.  How come it was never mentioned to me.  Yes I am TNBC  I will definitely chase that up. Was it written up in your pathology results or just something your Onc mentioned to you.  You've literally blown my mind as I can't believe it was never mentioned.  Thanks for that.  I'm certainly not going to dwell on it which is perhaps the reason it wasn't mentioned but would certainly like to know.  

@kitkatb
The following information on ki-67 I found on the internet. I have paraphrased some of it.

"Ki-67 is a protein in cells that increases as they prepare to divide into new cells. A staining process can measure the percentage of tumor cells that are positive for Ki-67. The more positive cells there are, the more quickly they are dividing and forming new cells. In breast cancer, a result of less than 10% is considered low, 10-20% borderline, and high if more than 20

Ki-67 is a cancer antigen (protein) found in growing, dividing cells but is absent in the resting phase of cell growth (when cells are not growing). The fact that Ki-67 is found in dividing cells makes it a good proliferation marker (since cancer cells rapidly grow and divide) to follow the progress of breast cancer.

When it comes to breast cancer, the Ki-67 test may be performed on a sample of breast cancer tissue to help predict the aggressiveness of the cancer. The test, performed by a pathologist, measures the level of Ki-67 expression in the cancer cells through a staining process."

Ki-67 indicates the rate of cell growth. The higher the percentage the more quickly the cells are dividing and forming new cells.  Less than 10% is considered low and more than 20% is considered high.

I think you’re TNBC like me? We typically have a higher Ki-67 and I think I read somewhere the average for TNBC is 50%.