Immunohistochemistry - ER
- Introduction to ER
- ER Uses
ER or Estrogen (Oestrogen) receptor, is one of the most widely used antibodies in Immunohistochemistry.
Picture 1 – ER in use
This antibody is mainly used to assist in determination of whether a breast case will respond to tamoxifen by working out the whether it is a ER+ tumour. This stains up the nuceli of breast epithelial cells and some carcinomas that are ER+. This can also stain up endometrial and myometrium epithelia as well.
ER positivity requires validation by use of several different levels of positivity to determine the level of Estrogen receptor.
Picture 2 – Levels of ER positivity
As you can see above, the level of positivity can vary and this is very important in the determination of whether the patient can be treated using the above drug. In general, breast tumours that are ER positive are easier to treat than those that show up as negative.