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The mainstay of breast cancer treatment is surgery when the tumor is localized, with possible adjuvant hormonal therapy (with tamoxifen or an aromatase inhibitor), chemotherapy, and/or radiotherapy. At present, the treatment recommendations after surgery (adjuvant therapy) follow a pattern. This pattern may be adapted as every two years a worldwide conference takes place in St. Gallen, Switzerland to discuss the actual results of worldwide multi-center studies. Depending on clinical criteria (age, type of cancer, size, metastasis) patients are roughly divided to high risk and low risk cases which follow different rules for therapy. Treatment possibilities include Radiation Therapy, Chemotherapy, Hormone Therapy, and Immune Therapy.
An online resource for helping to quantify the relative risks and benefits of chemotherapy v. hormonal therapy is Adjuvant! Online (see below).
In planning treatment, doctors can also use PCR tests like Oncotype DX or microarray tests like MammaPrint that predict breast cancer recurrence risk based on gene expression. In February 2006, the MammaPrint test became the first breast cancer predictor to win formal approval from the Food and Drug Administration. This is a new gene test to help predict whether women with early stage breast cancer will relapse in five or 10 years, this could help influence how aggressively they fight the initial tumor.
The emotional impact of cancer diagnosis, symptoms, treatment, and related issues can be severe. Most larger hospitals are associated with cancer support groups which can help patients cope with the many issues that come up in a supportive environment with other people with experience with similar issues. Online cancer support groups are also very beneficial to cancer patients, especially in dealing with uncertainty and body-image problems inherent in cancer treatment.
Surgery
Depending on the staging and type of the tumor, just a lumpectomy (removal of the lump only) may be all that is necessary or removal of larger amounts of breast tissue may be necessary. Surgical removal of the entire breast is called mastectomy.
While there has been an increasing utilization of lumpectomy techniques for breast-conservation cancer surgery, mastectomy may be the preferred treatment in certain instances:
* Two or more tumors exist in different areas of the breast (a "multifocal" cancer).
* The breast has previously received radiation (XRT) treatment.
* The tumor is large relative to the size of the breast.
* The patient has had scleroderma or another disease of the connective tissue, which can complicate XRT treatment.
* The patient lives in an area where XRT is inaccessible.
* The patient is apprehensive about their risk of local recurrence after lumpectomy.
Standard practice requires the surgeon to establish that the tissue removed in the operation has margins clear of cancer, indicating that the cancer has been completely excised. If the tissue removed does not have clear margins, then further operations to remove more tissue may be necessary. This may sometimes require removal of part of the pectoralis major muscle which is the main muscle of the anterior chest wall.
During the operation, the lymph nodes in the axilla are also considered for removal. In the past, large axillary operations took out ten to forty nodes to establish whether cancer had spread. This had the unfortunate side effect of frequently causing lymphedema of the arm on the same side, as the removal of this many lymph nodes affected lymphatic drainage. More recently, the technique of sentinel lymph node (SLN) dissection has become popular, as it requires the removal of far fewer lymph nodes, resulting in fewer side effects. The sentinel lymph node is the first node that drains the tumor, and subsequent SLN mapping can save 65-70% of patients with breast cancer from having a complete lymph node dissection for what could turn out to be a negative nodal basin. SLN biopsy is indicated for patients with T1 and T2 lesions (<5cm) and carries a number of recommendations for use on patient subgroups.
Radiation therapy
Radiation therapy consists of the use of high powered X-rays or gamma rays (XRT) that precisely target the area that is being treated. These X-rays or gamma rays are very effective in destroying the cancer cells that might recur where the tumor was removed. These X-rays are delivered by a machine called a linear Accelerator or LINAC. Alternatively, the use of implanted radioactive catheters (brachytherapy), similar to those used in prostate cancer treatment, is being evaluated. The use of radiation therapy for breast cancer is usually given after surgery has been performed and is an essential component of breast conserving therapy. The purpose of radiation is to reduce the chance that the cancer will recur.
Radiation therapy works for breast cancer by eliminating the microscopic cancer cells that may remain near the area where the tumor was removed during surgery. Since by the nature of radiation and its effects on normal cells and cancer cells alike the dose that is given is to ensure that the cancer cells are eliminated. However, the dose cannot be given in one sitting. Radiation causes some damage to the normal tissue around where the tumor was but normal healthy tissue can repair itself. The treatments are given typically over a period of five to seven weeks, performed five days a week. Each treatment session takes about fifteen minutes per day. Breaking the treatments up over this extended period of time gives the healthy normal tissue a chance to repair itself. Cancer cells do not repair themselves as well as normal cells, which explains the efficacy of radiation therapy.
Although radiation therapy can reduce the chance that breast cancer will recur in the breast, it is much less effective in prolonging patient survival. The National Cancer Institute reviews this information. in a paragraph that begins:“Breast-conserving surgery alone without radiation therapy . . .” The NCI includes six studies; none of them found a survival benefit for radiation therapy. Abstracts from all six studies are available for review. Patients who are unable to have radiation therapy after lumpectomy should consult with a surgeon who understands this research and who believes that lumpectomy (or partial mastectomy) alone is a reasonable treatment option.
Indications for radiation
Indications for radiation treatment are constantly evolving. Patients treated in Europe have been more likely in the past to be recommended adjuvant radiation after breast cancer surgery. Radiation therapy is usually recommended for all patients who had (lumpectomy, quadrant-resection). Radiation therapy is usually not indicated in patients with advanced (stage IV disease) except for palliation of symptoms like bone pain.
In general recommendations would include:
* As part of breast conserving therapy of breast cancer when the whole breast is not removed (lumpectomy or wide local excision)
* After mastectomy: Patients with higher chances of cancer recurring such as : large primary tumor and involvement of 4 or more lymph nodes.
Other factors which may influence adding adjuvant radiation therapy:
* Tumor close to or involving the margins on pathology specimen
* Multiple areas of tumor (multicentric disease)
* Microscopic invasion of lymphatic or vascular tissues
* Microcopic invasion of the skin, nipple/areola, or underlying pectoralis major muscle
* Patients with <4 LN involved, but extension out of the substance of a LN
* Inadequate numbers of axillary LN sampled
Types of radiotherapy
Radiotherapy can be delivered in many ways. Most commonly this is done using radiation from linear accelerators. Since this is delivered from outside, one needs to restrict the amount of dose that can be given at one time so that normal tissues are not harmed. So the course usually lasts for several days, typically every day for 5 to 6 weeks.
New technology has allowed more precise delivery of radiotherapy in a portable fashion - for example in the operating theatre. Targeted intraoperative radiotherapy (TARGIT). is a method of delivering therapeutic radiation from within the breast using a portable x-ray generator called Intrabeam. It is undergoing clinical trials in several countries at present to test whether it can replace the whole course of radiotherapy in selected patients. It may also be able provide a much better boost dose to the tumour bed and appears to provide superior control. This will be tested in a Targit-B trial.
Side effects of radiation therapy
The side effects of radiation have decreased considerably over the past decades. Aside from general fatigue caused by the healthy tissue repairing itself, there will probably be no side effects at all. Some patients develop a suntan-like change in skin color in the exact area being treated. As with a suntan, this darkening of the skin will fade with time. Other side effects experienced with radiation include the fact that radiation therapy can and often does cause permanent changes in the color and texture of skin, in addition to:
* reddening of the skin
* muscle stiffness
* mild swelling
* tenderness in the area
* long-term shrinking of the irradiated breast
Along with improved cosmetic outcome of treatment with radiation, there have been improvements in the techniques that deliver radiation to the breast. One such new technology is using IMRT (intensity modulated radiation therapy), in which the radiation oncologist can change the shape and intensity of the radiation beam at different points across and inside the breast. This allows for a more focused beam of radiation directed at the tumor cells and leaves most of the healthy tissue unaffected by the radiation.
Another new procedure involves a type of brachytherapy, where a radioactive source is temporarily placed inside the breast in direct contact with the tumor bed (area where tumor was removed). This technique is called a Mammosite and is currently undergoing clinic trials.
The use of adjuvant radiation has significant potential effects if the patient has to later undergo breast reconstruction surgery. Fibrosis of chest wall skin from radiation negatively affects skin elasticity and makes tissue expansion techniques difficult. Traditionally most patients are advised to defer immediate breast reconstruction when adjuvant radiation is planned and are most often recommended surgery involving autologous tissue reconstruction rather then breast implants.
Systemic therapy
Systemic therapy uses medications to treat cancer cells throughout the body. Any combination of systemic treatments may be used to treat breast cancer. Systemic treatments include chemotherapy, immune therapy, and hormonal therapy.
Chemotherapy
Chemotherapy can be given both before and after surgery. Neo-adjuvant chemotherapy is used to shrink the size of a tumor prior to surgery. Adjuvant chemotherapy is given after surgery to reduce the risk of recurrence.
Several different chemotherapy regimens may be used. Determining the appropriate regimen depends on many factors, including the character of the tumor, lymph node status, and the age and health of the patient. Possible chemotherapy regimens include:
* CMF: cyclophosphamide, methotrexate, and 5-fluorouracil
* FAC: 5-fluorouracil, doxorubicin, cyclophosphamide
* AC (or CA): Adriamycin (doxorubicin) and cyclophosphamide
* AC with paclitaxel administered after the AC
* TAC: Taxotere (docetaxel), Adriamycin (doxorubicin), and cyclophosphamide
* FEC: 5-fluorouracil, epirubucin and cyclophosphamide for 6 cycles
* FEC for three cycles followed by docetaxel for three cycles
* Dose dense AC: doxorubicin and cyclophosphamide followed by paclitaxel
* TC: Taxotere (docetaxel) and cyclophosphamide
Since chemotherapy affects the production of white blood cells, a growth factor, e.g. pegfilgrastim, is sometimes administered along with chemotherapy. This has been shown to reduce, though not completely prevent, the rate of infection and low white cell count.
Chemotherapy has increasing side effects as the patient's age passes 65.
Hormonal treatment
Patients with estrogen receptor positive tumors will typically receive a hormonal treatment after chemotherapy is completed. Typical hormonal treatments include:
* Tamoxifen is typically given to premenopausal women to inhibit the estrogen receptors
* Aromatase inhibitors are typically given to postmenopausal women to lower the amount of estrogen in their systems
* GnRH-analogues
* ovarian ablation or suppression is used in premenopausal women
However, a recent statistic data shows breast cancer rate dropped dramatically in 2003 and the declining use of hormonal treatment could be the reason .
Targeted therapy
In patients whose cancer expresses an over-abundance of the HER2 protein the drug trastuzumab (Herceptin ®) is used to block the HER2 protein in breast cancer cells slowing their growth. This drug was originally used only in the treatment of patients with metastatic disease, however in the summer of 2005 two large clinical trials published results suggesting that patients with early-stage disease also benefit significantly from Herceptin.
Preclinical
Flax seeds
Preliminary research into flax seeds indicate that flax can significantly inhibit breast cancer growth and metastasis, and enhance the inhibitory effect of tamoxifen on estrogen-dependent tumors.
Alternative medicine
The use of traditional Chinese medicine to treat breast cancer has been claimed, but no successful clinical trials have yet been reported.
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Important notice:
The content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other
qualified health provider with any questions you may have regarding a medical condition.
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