About Breast Cancer > Principles of BC Management
Dr Kwan Wing Hong
M.B.,B.S.(HK),F.R.C.R., F.H.K.C.R., F.H.K.A.M. (Rad)
Management of breast cancer entails a multidisciplinary approach including the close collaboration of surgeons, diagnostic radiologists, pathologists, clinical oncologists, or medical and radiation oncologists, breast cancer nurses and physiotherapists. Majority of early operable disease are curable. Innovative surgical techniques had significantly improved cosmetic outcome while maintaining the same level of cure as compared with the gold standard mastectomy. Prognosis of advanced or metastatic disease is grave but modern treatment could prolong survival and improve quality of life.
Surgery, radiation therapy, hormonal manipulation, cytotoxic and monoclonal antibody treatments are effective tools to treat breast cancer. The side effect profile and indication of these treatment modalities are different. Conservative surgical procedure will produce a better cosmetic outcome over mastectomy but could only be offered to patients who meet the selection criteria. Hormonal treatment is only useful in patients whose tumour expresses hormone receptor. Young patients generally tolerate chemotherapy much better. Targeted therapy with a monoclonal antibody called Herceptin is of clinical use in patients whose tumour strongly overexpress HER 2.
Treatment of breast cancer consists of a local and a systemic component because breast cancer tends to have occult systemic spread early in its clinical course. Such small metastasis are too tiny to be picked up by the best currently available imaging modality. Clinical trials in the past 30 years have demonstrated that adjuvant systemic treatment after surgery could eliminate these micrometastasis resulting in a lower relapse rate and a better survival. Chemotherapy and hormonal therapy are both effective treatment modality; each being able to reduce the recurrence by about one third. Therefore the use of adjuvant systemic treatment in patients with higher stage disease will result in a larger gain in survival.
Patients with early operable disease are normally operated first by either removing the whole breast (mastectomy) or part of the breast (breast conserving surgery). Preoperative chemotherapy may be considered to reduce the size of the tumour in those individuals who have a relatively large tumour initially and a strong desire to conserve their breast. Postoperative irradiation to the breast is mandatory for those individuals receiving breast conserving therapy. Adjuvant systemic treatment is indicated in a great majority of early staged patients to eradicate occult systemic micrometastasis. In general, adjuvant chemotherapy is given to young patients who could tolerate the drug well. In selected group of elderly patients with good general condition and relatively higher risk of relapse, chemotherapy may also be considered. In order to get the maximum benefit from cytotoxic treatment, chemotherapy should be commenced within six weeks of surgery. Four to eight cycles of drugs in 2-4 week intervals are delivered depending on the stage of disease, physical condition of the patient and doctor’s preference. Adjuvant hormonal treatment is useful in patients whose tumour expresses hormone receptor. Tamoxifen is the gold standard of hormonal therapy but new clinical data suggested that aromatase inhibitors may have a superior therapeutic effect than tamoxifen in postmenopausal patients. Hormonal therapy is usually taken for five years.
Patients with locally advanced disease, including those whose tumour erodes through the skin or fixed to the chest wall or fixed axillary lymph nodes, are generally given neoadjuvant chemotherapy with the aim of shrinking the main tumour bulk to facilitate subsequent surgical resection and to control micrometastasis before operation. In elderly patients whose disease is hormone responsive, upfront hormonal therapy may be used instead prior to surgical resection. Further adjuvant systemic treatment as described above are offered after surgery.
Long term prognosis of patients with metastatic disease is grave. Principle of treatment is palliative with the aim of prolonging survival and improving quality of life. Both chemotherapy and hormonal treatment are effective measures. In general patients with metastasis to major internal organs like lung and liver are given chemotherapy while those with lymph node and bone secondaries are offered hormonal therapy. Monoclonal antibody treatment with a drug called Herceptin is proven clinically beneficial to patients whose tumour strongly overexpresses an antibody named HER 2. Radiotherapy effectively palliate symptoms due to brain and skeletal secondaries. Bisphosphonate treatment would alleviate the pain due to bone metastasis and reduce subsequent skeletal complications.