Breast cancer treatment

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. Treatment possibilities include radiation therapy, chemotherapy, hormone therapy, and immune therapy.

NCCN provides clinical practice guidelines for various types of breast cancer.

Surgery

Surgical removal of the entire breast is called mastectomy.

Lumpectomy techniques are increasingly utilized for breast-conservation cancer surgery.

• Two or more tumors exist in different areas of the breast (a "multifocal" cancer).
• The breast has previously received radiotherapy.

Radiation therapy

Radiation therapy involves using high-energy X-rays or gamma rays that target a tumor or post surgery tumor site. This radiation is very effective in killing cancer cells that may remain after surgery or recur where the tumor was removed. Radiation therapy for breast cancer is usually performed after surgery and is an integral component of breast-conserving therapy.

Radiation therapy eliminates the microscopic cancer cells that may remain near the area where the tumor was surgically removed. The dose of radiation must be strong enough to ensure the elimination of cancer cells. However, radiation affects normal cells and cancer cells alike, causing some damage to the normal tissue around where the tumor was. Healthy tissue can repair itself, while cancer cells do not repair themselves as well as normal cells.

Although radiation therapy can reduce the chance of breast cancer recurrence, it is much less effective in prolonging patient survival.

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).

• As part of breast conserving therapy when the whole breast is not removed (lumpectomy or wide local excision)
• After mastectomy: Patients with higher chances of cancer recurring because of conditions such as a large primary tumor or substantial involvement of the lymph nodes.
• Multiple areas of tumor (multicentric disease)

Types of radiotherapy

However there is yet to be a demonstrated difference in treatment outcomes (both tumor recurrence and level of side effects) for IMRT in breast cancer when compared to ordinary radiotherapy treatment.

Side effects of radiation therapy

However many breast cancer patients develop a suntan-like change in skin color in the exact area being treated.After surgery, radiation and other treatments are complete many patients notice the affected breast seems smaller or seems to have shrunk.

The use of adjuvant radiation has significant potential effects if the patient has to later undergo breast reconstruction surgery.

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.

Hormonal treatment

Patients with estrogen receptor positive tumors will typically receive hormonal therapy after chemotherapy is completed. Typical hormonal treatments include:

• The drug is less effective in postmenopausal breast cancer patients who had a deficiency in the CYP2D6 gene, which is key for activating tamoxifen and many other drugs.
  

The patients whose tumors showed an increased glucose uptake, called a PET flare, were the same patients who benefited from estrogen therapy. It's too early to know why estrogen has a negative effect on metastatic breast cancer tumors.

Targeted therapy

In patients whose cancer expresses an over-abundance of the HER2 protein, a monoclonal antibody known as trastuzumab (Herceptin) is used to block the activity of the HER2 protein in breast cancer cells, slowing their growth. In the advanced cancer setting, trastuzumab use in combination with chemotherapy can both delay cancer growth as well as improve the recipient's survival.

Target	Drug	Type	Efficacy Trial
ER/PR	Anastrozole(Arimidex) Letrozole(Femara)	Aromatase inhibitor
	Exemestane(Aromasin) Fulvestrant(Faslodex)	Other
HER2 receptor protein	Trastuzumab(Herceptin), Pertuzumab	Monoclonal antibody
	lapatinib(TykerB)	Kinase inhibitor
	NeuVax dHER2 MVF-HER-2	Vaccine	NeuVax is a HER2/neu peptide-based T-cell immunotherapy aimed at preventing disease recurrence and prolonging survival in cancer patients that have tumors expressing the HER2/neu oncoprotein. To date, clinical study results have demonstrated that NeuVax significantly reduces the rate of cancer recurrence while showing minimal side effects
	E1A (gene therapy)	Other
HER1/ EGFR	Iressa (gefitinib)	tyrosine kinase inhibitor	However, clinical studies did not find most EGFR inhibitors effective against breast cancer for a large enough proportion of patients. Some oncologists believe it may be possible to select a fraction of patients, either through genetics or the characteristics of their tumors, who have a better chance of having the drugs work
IGF-1 receptor protein (insulin-like growth factor-1)	IMC-A12 CP-751, 871 AMG 479 h7C10	Monoclonal antibody
	OSI-906	Kinase inhibitor
PI3K/AKT/mTOR cell survival pathway	BGT226 BEZ235A RAD001 Rapamycin	Kinase inhibitor
VEGF receptor protein (involved in forming tumor blood vessels)	Bevacizumab(Avastin)	Monoclonal antibody	The results of a recent clinical trial showed that bevacizumab (Avastin) is an effective addition to chemotherapy in women with metastasized breast cancer. Bevacizumab blocks the growth of blood vessels that can feed the tumor and promote growth. Targeted therapy with novel (newly discovered) therapies is in the forefront of ongoing research.
	Sunitinib Vatalinib Pazopanib AZD2171 AMG706	Kinase inhibitor
	AMG386 PTC299	Other
P53	P53 peptide vaccine	Vaccine
	Gendicine (from China)	Gene therapy
	ALT801 (p53 inhibitor) Ad5CMV-p53 (or INGN 201)(gene therapy) Anti-p53 T-cell reinfusion	Other
Other Targets	Dasatinib (SRC inhibitor)	Kinase inhibitor
	AS1402 anti-MUC1 antibody THERATOPE Dendritic cell vaccines	Vaccine
	AZD2281 (PARP protein inhibitor) BSI-201 (inhibitor) C1311 in phase II trial (topoisomerase II inhibitor)	Other

Flax

The preliminary research into flax seeds indicates that flax can significantly change breast cancer growth and metastasis, and enhance the inhibitory effect of tamoxifen on estrogen-dependent tumors.

Immuno Therapy

Harnessing Infection to Fight Cancer by activating the immune system (experimental).

The human immune system does battle cancer.

Alternative treatments

A wide range of alternative non medical treatments of breast cancer have been proposed. Beyond conventional TNM staging, doctors can now order a gene expression profile on tumors to predict whether a breast cancer patient will have a high chance of developing breast cancer again.

Treatment response assessment

• MRI accurately detects residual breast tumors after radiofrequency ablation
• water diffusion MRI — a potential new biomarker of response to cancer therapy

Managing Side Effects

Around a third of patients with cancer use complementary therapies, including homeopathic medicines, to try to reduce these side effects.