The Use of IMRT Technique in Breast Cancer

The aim of radiation therapy to the breast is to kill cancer cells that could persist after therapy and cause breast cancer to relapse locally. Radiation therapy is utilized aspart of the overall breast-conserving strategy because radiation decreases the risk of local cancer recurrence and improves survival. Patients with DCIS treated with mastectomy do not need treatment with radiation therapy. Radiation therapy after a lumpectomy decreases the risk of cancer recurrence. Patients with node negative stage I breast cancers treated with breast-conserving surgery utilizing a lumpectomy are currently recommended to receive additional treatment with radiation therapy.Patients with node negative stage II breast cancers treated with breast-conserving surgery utilizing a lumpectomy are currently recommended to receive additional treatment with radiation therapy because radiation decreases the risk of local cancer recurrence and improves survival. The role of radiation therapy following mastectomy in women with stage II or III breast cancer is somewhat controversial. Radiation therapy was not typically recommended for women with stage II or III breast cancer treated with mastectomy.Current evidence increasingly supports the use of radiation following surgery and chemotherapy in women with stage II or III breast cancer. Certain groups of women known to be at high risk of local breast cancer recurrence should strongly consider radiation therapy. These include: Cancer greater than 5 centimeters in greatest dimension; 4 or more involved axillary lymph nodes; Cancer involving the margin of resection. Radiation therapy also plays an important role in women with stage IV or recurrent breast cancer. Radiation therapy also plays an important role in providing symptomatic relief from advanced breast cancer. Patients developing metastatic cancer to the bone, skin,selected lymph nodes, and other sites can achieve a complete remission when treated with radiation to the site of cancer recurrence. Radiation can relieve symptoms from cancer and prevent fractures of bones when used early. IMRT is a newer method of delivering radiation to target structures that differs from traditional methods of radiation delivery. The basis of IMRT is the use of intensity modulated beams that can provide two or more intensity levels for any single beam direction and any single source position.IMRT treatment plans are able to generate concave dose distributions and dose gradients with narrower margins than those allowed using traditional methods. This fact makes IMRT especially suitable for treating complex treatment volumes and avoiding close proximity organs at risk (OAR) that may be dose limiting. IMRT theoretically may provide benefits in terms of increased tumour control through escalated dose and reduced normal tissue complications through OAR sparing. The main benefit expected with IMRT is a reduction in adverse event rates, especially those associated with radiation damage to nearby OAR. IMRT has the capacity to deliver biologically effective doses to the planned target volume while avoiding nearby tissue and OAR, the expected result would be fewer adverse effects but similar treatment-related outcomes, and this evidence review continues to support this. No evidence was found to suggest that this reduction in toxicity comes at a price of higher recurrence rates