If breast cancer is detected early by mammography -- that is, before the tumor has spread out to other areas of the breast or other regions of the body, such as lymph nodes, bones, liver, brain, etc., the tumor can be easily excised or removed completely by surgery.
Cancer is early when it is still "in situ" (in its place). It is late when it has become "invasive or infiltrating", i.e., the tumor has broken through the ducts and lobules of the breast to spread via the blood stream and lymphatics to other areas.
In situ cancer is easily treated with surgical excision (called "lumpectomy") without removing the entire breast. Even bigger cancers can now be removed in a limited way, or treated "conservatively" as opposed to "radically", as long as radiation is performed after surgery. Nevertheless, modified radical mastectomy is still considered the gold standard of treatment, until, perhaps, the advent of comprehensive genetic oncology (genetic treatment of cancer).
Dr. William S. Halsted, the father of American Surgery, developed the surgical treatment for breast cancer in New York and was the first to perform a radical mastectomy in 1882. For almost the next century, Halsted's operation became the standard treatment for breast cancer. In 1978, Dr. Bernard Fisher, from the University of Pittsburg, published a study which showed that lumpectomy (or limited breast resection) coupled with radiation therapy was as effective as total radical mastectomy. This led to a change in how breast cancer is currently treated. In the 1990s, sentinel node biopsy was developed to refine the removal of axillary nodes which determines whether cancer is localized or already spread out to the lymph glands.
Depending on the biological behavior of the cancer, its size, hormone dependence, etc., there is now an array of treatment modalities available.
When a tumor is detected by mammogram (remember, most breast cancers present as painless lesions), a choice can be made between a needle biopsy with ultrasound or stereotactic guidance (with the patient awake) or an open biopsy in the operating room under anesthesia (with the patient asleep).
The tissue that is sampled is then sent to pathology for a series of tests. Pathologists will examine the tissue under the microscope to determine if the lesion is cancer (malignant) or if it is not (benign fatty tissue, fibroadenoma, cyst, etc.). If the biopsy is positive for cancer, the patient can discuss with her surgeon the necessity of removing only a portion of the breast or removing the entire breast (with or without plastic surgery reconstruction).
If a limited resection is the choice, the patient will have to undergo radiation as well to guarantee that microscopic cancer cells, outside of the area of resection, are eradicated. If the entire breast is removed and the axillary nodes are found to be clean or free of cancer cells, no further treatment aside from hormonal treatment, such as the antiestrogen Tamoxifen, may be necessary. However, if the axillary lymph nodes are positive, adjuvant chemotherapy might be beneficial, regardless of the side effects.
Chemotherapy, which is started only after the surgical wound has healed, usually requires placement of a MediPort or access chamber into the subclavian vein so that powerful drugs such as clyclophosphamide, methotrexate, fluorouracil adriamycin, etc. can be safely administered for 3-6 months. External beam radiation for 5-7 weeks might also be necessary. Internal radiation or brachytherapy is an option. The latter involves low-dose or high dose implantation of radioactive substances.
Other treatments are put in place depending on whether the cancer is estrogen postive, progesterone positive or if there is overexpression or amplification of HER2/neu gene ( 15-20% of breast cancers) which is associated with a worse prognosis and higher recurrence rate. The monoclonal antibody trastuzumab (Herceptin) may be effective in these aggressive types of breast cancer.
The take home message is that breast cancer comes in many forms and can be treated in a variety of ways. The most important message to women in their 40s is: get your yearly mammogram.
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