External Breast Radiation Methods
External beam breast radiation (EBI) is done to kill breast cancer cells that may remain after surgery to prevent recurrence, or to slow down or shrink an existing breast tumor. The most common type of radiation treatment for breast cancer is some form of external beam radiation. External beam breast radiation may cover the entire breast or it may target only the tumor bed.
Preparing For External Radiation
Before you begin radiation therapy, your radiation oncologist will carefully plan your treatment. The amount of radiation and the area that will be covered depend on how extensive your cancer and your surgery were and your lymph node status. You may need to have ultrasounds, MRI, or CAT scans done to help locate and measure the tissue that needs treatment. Special X-rays, called port films, will be taken of the target area to check the aim of the radiation beams. A simulation session will be done to make sure that your treatment will be accurate as possible and avoid radiation exposure to healthy tissue. Your clinic may use tiny tattoos or temporary ink marks on your breast skin to use as guidelines during treatments. If you're having chemotherapy, radiation will usually be scheduled after you've finished all your infusions; however, sometimes radiation and chemotherapy may be given together.
Conventional External Breast Radiation
Conventional external beam radiation therapy covers your entire breast and in some cases your underarm lymph node area. This type of treatment is called whole breast radiation (WBI) and is given daily Monday through Friday for six weeks. If you don't live near a radiation clinic, ask your oncologist about accelerated whole breast radiation. You may be able to have accelerated whole breast radiation, which can be completed in three weeks.
Personalized External Beam Partial Breast Radiation
Small early-stage breast cancers may be treated from within the breast by brachytherapy, but others may qualify for external beam partial breast radiation (EB-PBI). These personalized therapies require careful planning and monitoring, and may be done with image-guided radiotherapy (IGRT) equipment. Some types of EB-PRI use 3D Conformal Radiation Therapy, which employs external X-ray, proton, or neutron beams, while others use Intensity Modulated Radiotherapy (IMRT). Just as for whole breast radiation, a machine from outside your body will aim the energy, but it will focus on a limited area of your breast. Partial breast radiation limits damage to healthy tissue, speeds recovery, and has few side effects. Sometimes an extra dose of radiation, called a boost, will be done just to the tumor bed, as extra insurance against recurrence.
Treatment and Recovery From External Breast Radiation
External beam radiation may cause some side effects, such as fatigue, radiation dermatitis, fibrosis, swelling, and tenderness of the radiated area. If your underarm area is included in radiation, you may experience arm lymphedema. Most of these side effects will disappear in a few weeks or months after completing treatment. Wear loose clothing made of soft natural fibers, with a soft, wire-free bra, and use hydrating skin care creams and ointments to give comfort and speed your recovery. Ask your radiation oncology team for advice about skin care and how to use those properly during treatments and recovery.
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