BREAST CANCER INDIA

Correct information is .. half the war won already

HORMONE THERAPY FOR BREAST CANCER




What are hormone receptors?

A 'receptor' on a cell is a small 'item', expressed on the surface of a cell. There are many such different receptors on the surface of a cell. Each receptor has ability to bind to one or a few particular circulating substances (usually hormones and similar substances), and is specific for that substance. It is a sort of a male female connection; meaning, the receptor may be a 'female' with a small gap in it, in which the circulating substance will come and 'fit' into it. Once this 'connection' of the circulating substance - receptor occurs, the receptors causes a series of changes inside a cell.



What is the role of hormone receptors in breast cancer?

In case of breast cancer, the circulating substance is the female hormone 'estrogen' and the receptor on the cell of the breast is 'estrogen' receptor. Estrogen is a hormone which is normally present in females, it binds to the estrogen receptor on the cells of the breast, and causes the cancer cell to divide rapidly. Thus, estrogen is responsible for the growth of the tumour. Similarly, there are receptors for the other female hormone called progesterone. But the most important one is the Estrogen Receptor (ER). From the above, it is logical that if we could stop the interaction between the estrogen and the receptor, we could decrease the growth of the tumour which expresses ER. And we could prevent further occurences of an ER dependent breast cancer. Not all breast cancers express hormone receptors, but in those that express, we have a chance to intervene there.



What percentage of breast cancers are hormone receptor positive?

About 80% to 85% of breast cancers are hormone receptor positive. These hormone receptors include Estrogen Receptor (ER) and Progesterone Receptor (PR). In general, most post menopausal women are hormone receptor positive. Of the 15% patients of breast cancer who will be ER/PR negative, majority tend to be premenopausal patients.



How does one test for the hormone receptor status?

The test for Hormone receptor status is done in a pathology laboratory, on the cancerous tissue of the affected breast. The specimen for testing of hormone receptors can be any of the following types:

  • Core Biopsy: In patients where we are going to give chemotherapy first (locally advanced cancer, large operable tumour etc.), and then follow it with surgery, a Core Biopsy is a must. Hormone receptor status can be tested on a core biopsy specimen. The reason for core biopsy in such cases is that, in a fair number of patients in whom chemotherpy is given first, the tumour disappears completely, and no tumour remains for any further testing. Hence, for any patient, where we plan a chemotherapy first, a core biopsy is a must. Because, the hormonal receptors status CANNOT be tested on FNAC slide, please note.

  • Surgery Specimen: In patients where we decide surgery first, the hormone receptor status is tested on the surgical specimen (either the specimen of a wide excision lumpectomy or the whole breast, depending on which surgery is done).