During the removal of the breast can not excise all the breast tissue, especially immediately adjacent to the skin and run along the pectoral muscles. In most cases, if after such an operation is a little glandular tissue, she is developing normally. However, in the remaining tissue may be some cancer cells that may be the cause of recurrence of breast cancer. The extent of this risk may be low or high, depending on the nature and extent of the tumor. Therefore, based on different data histology of the tumor removed, your doctor may prescribe radiation therapy after surgery.
With a high risk of tumor recurrence after mastectomy are associated the following factors:
Tumor size greater than 5 cm (there may be a tumor or a few together form a 5-cm)
Cancer has spread to the lymph and blood vessels,
The tumor removed with clean margins is not (that is, the edges of the removed tissue are cancerous cells).
Cancer defeated four or more lymph nodes or damage of at least one lymph node in premenopausal women.
Cancer has on the skin of the breast (eg, in the form of inflammatory cancer).
These factors increase the risk of breast cancer recurrence after mastectomy and 20 - 30%.
In order to reduce this risk and is assigned to radiation therapy, which helps to reduce it by two thirds, for example, if the risk was 30%, radiotherapy reduces it to 10%). Irradiation is carried out in the area where the tumor was removed, and sometimes in the lymph nodes.
In some patients the risk of cancer recurrence moderate. They seem to be on the verge of high and low risk of recurrence. An example of this might be a situation when the tumor diameter is 4 cm and two affected lymph nodes. The doctor and patient should carefully assess the specific situation. Most women want to do everything possible to fashion a more reduce their risk of cancer recurrence. But some women may opt out of radiation therapy, assessing their chances with your doctor.
It should be noted that in most cases (70%) after mastectomy does not require radiation therapy.