The whole rationale of adjuvant therapy is that it is easier to cure cancer when there are only a few (relative term) cancer cells in the body than when there is full blown relapse – hence therapy is often given after an operation which by itself appears to have removed the only known site of disease.
Tumour cells that express hormone receptors (the proteins that are present in normal breast duct cells and sense and respond to oestrogen hormone and which are retained by some breast cancer cells) will respond to drugs targeted at either blocking these receptors (e.g. tamoxifen) or deprive the body of oestrogen (GnRH antagonists and aromatase inhibitors). These medications carry fewer side effects than chemotherapy and have an important role in the adjuvant therapy of patients with hormone receptor positive disease and are given for up to five years after the diagnosis.
Larger or more extensive breast cancer (without overt spread beyond the breast and regional lymph nodes) may be treated by primary total mastectomy (sometimes with immediate reconstruction of the breast shape by subcutaneous prosthetic implant) or even primary chemotherapy to shrink the tumour down in size prior to operation. Such patients are more likely to receive all modalities of therapy – viz. chemotherapy, hormonal therapy, surgery, radiotherapy and nowadays the molecular agents. These last are of great interest. Where a breast cancer expresses a surface membrane protein called Her-2 (approximately 20% of cases) then this tumour is being driven to multiply in an above average, aggressive way by a particular oncogene. In the last few years, an inhibitor of Her-2 (trastuzumab) has been shown to further improve the results of adjuvant therapy in terms of long term disease survival (which we expect to equate with cure), and an orally active version of this therapy (lapitinib) is now becoming available.
It has now been unequivocally demonstrated that improved adjuvant therapy – wisely chosen and bespoke for individual patients and based on the risk characteristics of their tumour and its staging at presentation to the doctor – will increase the cure rate of this disease and it is therefore critical that this is assessed optimally at the outset.
Modern treatment relies on a multimodality approach (involving experts in surgery, radiology, histopathology, oncology and others). The team at The Oncology Clinic at 20 Harley Street in London has long term experience in the field, introduced the specific aromatase inhibitors to Europe and has published widely in scientific medical journals on optimal therapy in breast cancer.
Further information on breast cancer is available on the Cancer Advice web site.