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BREAST CANCER Treatment
Surgery, Radiation therapy, Indications
for radiation,
Types of radiotherapy, Side effects of radiation therapy,
Systemic therapy, Chemotherapy, Hormonal treatment,
Targeted therapy, Preclinical, Flax seeds, Alternative medicine
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 it was reported by
NewsMax.com that the MammaPrint test is 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.
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 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 abd 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.[40] 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
Tumor close to or to 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) (coined by Dr Jayant S Vaidya in
1999) 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 improved 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 do 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 are: (((radition
therapy can and often does cause permanent changes in the color and
texture of skin)))
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 are
also other techniques for delivering radiation to the breast. One such new
technology is using IMRT (intensity modulated radiation therapy) 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 an
even more focused beam of radiation directed at the tumor cells and
leaving 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.
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.
There are several different chemotherapy regimens that may be used. The
determination of 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: doxorubicin and cyclophosphamide
AC with paclitaxel administered after the AC
TAC: docetaxel , 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 block the estrogen
receptor on cells to prevent the transport of estrogen into the cell
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 hormone could be the reason
[6].
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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History of breast cancer
Types of breast cancer
Risk factors and etiology
Age
Alcohol
Environmental causes
Genes
Hormones
Light levels
Obesity
Unproven
Prevention in high-risk
individuals
Prevention of
Environmental Causes
Symptoms
Screening
Diagnosis
Treatment
Surgery
Radiation therapy
Indications for radiation
Types of radiotherapy
Side effects of
radiation
Systemic therapy
Chemotherapy
Hormonal treatment
Targeted therapy
Preclinical
Flax seeds
Alternative medicine
Prognosis
Breast cancer in males
Spreading elsewhere
Breast cancer awareness
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