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Patients & Visitors

Breast Unit

Endocrine Treatment

When the breast cancer cells are looked at under the microscope, the pathologist will look to see if there are any oestrogen receptors in the cells. If these are seen, then the breast cancer is termed ER positive.

If the breast cancer is ER positive then it is likely that endocrine treatment will be recommended. This is usually Tamoxifen for premenopausal women and an Aromatase inhibitor (e.g. Anastrozole) for post menopausal women. At the moment this treatment is usually recommended for 5 years.

If you have been prescribed an aromatase inhibitor (anastrozole, letrozole, exemestane), then a bone density scan will be arranged for you at the RNHRD and Brownsword therapies centre. As aromatase inhibitors can cause osteoporosis, your bone density is measured soon after treatment starts to ensure that you do not suffer from osteoporosis and occasionally an extra treatment in recommended to reduce your risk of osteoporosis.

If you are prescribed Tamoxifen, then we would recommend that this is stopped for a month before any major surgery. It should be restarted a month following surgery. This is to reduce the risk of deep vein thrombosis. It is imperative that appropriate contraception is used to avoid pregnancy for all patients on Tamoxifen.

Clinical trials continue to be done and the length of time patients' stay on endocrine treatment may change for some women in the future.

These tablets reduce the effect of oestrogen on the breast cancer cells and can cause breast cancer cell death. If a tumour is ER positive we would recommend that oestrogen containing HRT or oestrogen creams are avoided. This can be a problem for some of our patients and we would encourage patients to discuss this with us in clinic if that was the case.

Endocrine treatment and surgery

Endocrine treatment is often given after surgery, on some occasions it is given as the first treatment, for a period of time before surgery. Often this is used with the aim to shrink down the tumour to enable successful breast conserving surgery. An aromatase inhibitor is started soon after the diagnosis has been given and continues for 16 weeks. At 16 weeks an ultrasound and mammogram is done and surgery planned.

For patients, with an ER positive tumour who have many medical problems that would render them not fit enough for an operation, endocrine treatment without surgery may be offered. These patients are seen regularly in clinic to ensure there is a response to the treatment offered.

Side effects

Although endocrine treatments are usually well tolerated, some women find specific side effects difficult to cope with. If so, we encourage women to ring our breast care nurses who usually arrange a clinic appointment to discuss side effects and often offer an alternative.

Also See:




Endocrine Treatment

Care after treatment

Breast Cancer Support Groups

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