HER2 Support Group Forums - View Single Post - cut-off point used to determine her2 amplification to be lowered?

Hopeful · 01-16-2008, 11:09 AM

Lani,

I think the article I was trying to recall was this one: http://jco.ascopubs.org/cgi/content/full/25/1/118

I think prior to this guideline change, 10% of the tumor had to stain positive for Her2 by IHC to be considered Her2+++, and it was raised to 30% (see http://jco.ascopubs.org/cgi/content-nw/full/25/1/118/T2 for the old standard and http://jco.ascopubs.org/cgi/content-nw/full/25/1/118/T4 for the revised one)

I have been curious about the change in standard, as I was dx in June of 2006, under the old algorithm, and wonder if the result would be different under the new one?

The point about Herceptin being of benefit to women who are less than Her2+++ by IHC has drawn interesting responses from the medical community. The initial responses I saw were to criticize the testing methods as being incosistent/unreliable in that they found results from different labs not easily reproducible. I think this may explain some instances but not all. I have seen more studies that are looking at how the signalling pathways are utilized by the cancer. It appears that Herceptin may block some signalling that occurs in patients that are not Her2+++, making this cut-off for determining Herceptin response unreliable.

The goal, I think, is to try to find out who might benefit from Herceptin and who will not. In this regard, I think there are more issues than just the magnitude of Her2+. For example, I have been reading papers lately about the interaction of all the Her family members and its relationship to outcomes for bc patients. It seems Her3 is a big influence in conjunction with Her2 combined with endocrine status. However, since all of the focus is on Her2 testing, we are losing a valuable part of the picture in trying to discern which Her2+ bc tumors are the most aggressive and amenable to certain types of tx when not testing for the other Her2 family members. It is unrealistic to expect that one marker will hold the key in a disease as complex as bc.

Hopeful

01-16-2008, 11:09 AM	#7
Hopeful Senior Member Join Date: Aug 2006 Posts: 3,380	Finally found what I was looking for Lani, I think the article I was trying to recall was this one: http://jco.ascopubs.org/cgi/content/full/25/1/118 I think prior to this guideline change, 10% of the tumor had to stain positive for Her2 by IHC to be considered Her2+++, and it was raised to 30% (see http://jco.ascopubs.org/cgi/content-nw/full/25/1/118/T2 for the old standard and http://jco.ascopubs.org/cgi/content-nw/full/25/1/118/T4 for the revised one) I have been curious about the change in standard, as I was dx in June of 2006, under the old algorithm, and wonder if the result would be different under the new one? The point about Herceptin being of benefit to women who are less than Her2+++ by IHC has drawn interesting responses from the medical community. The initial responses I saw were to criticize the testing methods as being incosistent/unreliable in that they found results from different labs not easily reproducible. I think this may explain some instances but not all. I have seen more studies that are looking at how the signalling pathways are utilized by the cancer. It appears that Herceptin may block some signalling that occurs in patients that are not Her2+++, making this cut-off for determining Herceptin response unreliable. The goal, I think, is to try to find out who might benefit from Herceptin and who will not. In this regard, I think there are more issues than just the magnitude of Her2+. For example, I have been reading papers lately about the interaction of all the Her family members and its relationship to outcomes for bc patients. It seems Her3 is a big influence in conjunction with Her2 combined with endocrine status. However, since all of the focus is on Her2 testing, we are losing a valuable part of the picture in trying to discern which Her2+ bc tumors are the most aggressive and amenable to certain types of tx when not testing for the other Her2 family members. It is unrealistic to expect that one marker will hold the key in a disease as complex as bc. Hopeful