HER2-low is a clinically significant subgroup
IHC 0
IHC 1+
IHC 2+/ISH-
IHC 3+
IHC 2+
ISH+
100% of breast cancer’s tested for HER2
Traditionally
HER2 Negative
~85%
HER2 Positive
~15%
~60% of
HER2 Negative
NOW CLASSIFIED
as HER2-low
{
{
{
HER2 Negative
~25%
Experience the data
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![](media/9c4e8b9ed3da8cb543113ce2aa5941da/stage-4-overlay-01.png)