Breast cancer Guide, Meaning , Facts, Information and Description
Breast cancer is cancer of breast tissue. Worldwide, it is the most common form of cancer in females, affecting approximately 10% of all women at some stage of their life in the Western world. Although significant efforts are made to achieve early detection and effective treatment, about 20% of all women with breast cancer will die from the disease.
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2 Screening 3 Diagnosis 4 Treatment 5 Prognosis 6 Breast cancer awareness 7 External links |
Epidemiology
The risk of getting breast cancer increases with age. For a woman who lives to the age of 90 the odds of getting breast cancer her entire lifetime is about 12.5% or 1 in 8. Men can also develop breast cancer, although their risk is less than 1 in 1000 (see sex and illness). This risk is modified by many different factors. In some families, there is a strong inherited familial risk of breast cancer. Some racial groups have a higher risk of developing breast cancer - notably, women of European and African descent have been noted to have a higher rate of breast cancer than women of Asian origin. (figures from breastcancer.org)
Other established risk factors include having no children, having the first child later, not breastfeeding, early menarche (the first menstrual period), late menopause and taking hormone replacement therapy.
The probability of breast cancer rises with age but breast cancer tends to be more aggressive when it occurs in younger women. One type of breast cancer that is especially aggressive and disproportionately occurs in younger women is Inflammatory Breast Cancer. It is initially Staged as Stage IIIb or Stage IV. It also is unique because it often does not present with a lump so that it often is not detected by mammography or ultrasound. It presents with the signs and symptoms of a breast infection like Mastitis.
Two genes, BRCA1 and BRCA2, have been linked to the familial form of breast cancer. Women in families expressing these genes have a much higher risk of developing breast cancer than women who do not. Together with Li-Fraumeni syndrome (p53 mutations), these genetic abberations determine around 5% of all breast cancer cases, suggesting that the remainer is sporadic.
Screening
Due to the high incidence of breast cancer among older women, screening is now recommended in many countries. Screening methods suggested include breast self-examination and mammography. Only mammography has been proven to reduce mortality from breast cancer. In some countries routine (annual) mammography of older women is encouraged as a screening method to diagnose early breast cancer.
At this stage mammography is still the modality of choice for screening of early breast cancer. It is the gold-standard for other imaging methods such as ultrasound, NMR-tomography and CT which are less useful due to their lower spatial resolution. CT by itself is nearly useless for breast cancer screening as NMR-tomography provides better resolution and quality (and costs much more).
The mainstay of breast cancer diagnosis is the triad of clinical history, physical examination and imaging (either mammography or ultrasound). If clinically indicated, a suspicious lump will then be biopsied for histological confirmation of whether it is malignant or not. The biopsy is usually performed either with a fine needle guided by ultrasound or with a larger "core" needle. The diagnosis of breast cancer is confirmed by biopsy results.
A pathology report will usually contain a description of cell type and grade. The most common invasive breast cancer cell type is infiltrating ductal carcinoma. Other types include adenocarcinoma, and infiltrating lobular carcinoma.
After diagnosis, the next phase is tumour staging - this aims to measure the extent of the tumour and whether or not it has metastasized (spread to distant sites).
For suspicious, high risk cases, other investigations which include CT scans, nuclear medicine imaging, chest X-rays and blood tests will be done to look for any metastasis or secondary cancer that has spread a long way from the site of the primary tumour.
One way of categorising tumour is by staging it using the TNM (Tumour, Nodes and Metastasis) system, which in turn determines treatment recommendations. The TNM article also discusses some additional classifications, such as grading (how invasive are the cancer cells). Also note that the specific numbering in the TNM system depends on the type of cancer (breast, lung, etc.). For the standard numbering in breast cancer staging, see [1]. Some biological features of the cancer such as estrogen receptor and HER2-neu oncogene expression are also determined as they also affect treatment recommendations.
Depending on the staging and type of the tumour, 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.
Standard practice requires that the surgeon must 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 10-40 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 dissection has become popular as it requires the removal of far fewer lymph nodes, resulting in fewer side effects.
At present, the treatment recommendations 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 an 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. The following list is a compilation af possibilities:
Diagnosis
Despite efforts to increase screening of older women, most women have breast cancer first present to their family practitioner with a lump in their breast.Staging
The cancer is staged depending on factors which include the size of the tumour, whether there is lymph node involvement or not and whether there is distant spread of cancer cells. The subtype of inflammatory breast cancer is automatically staged as Stage IIIb or Stage IV if metastasis has occurred.Treatment
The mainstay of breast cancer treatment is surgery with adjuvant chemotherapy and/or radiotherapy.
For some early tumours, systemic treatments may not be recommended. Following mastectomy, radiation therapy may not be recommended if the number of lymph nodes involved are less. For advanced tumours, there is an established role for all three modalities of treatment (surgery, radiation, systemic therapy) as the combination produces the best results.
The emotional impact of cancer diagnosis, symtoms, 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.
On-line cancer support groups are also very beneficial to cancer patients, especially in dealing with uncertainty and body-image problems inherent in cancer treatment.
Prognosis
Long term outcome depends on the staging of the breast cancer at diagnosis and how well the cancer has been treated. Generally speaking, the earlier the cancer is detected, the better the prognosis.