radiation therapy for breast cancer | OCROC

What is radiation therapy for breast cancer?

Radiation therapy targets breast cancer cells with high-energy radiation in an attempt to kill them and shrink tumors. Radiation causes damage to the DNA of cancer cells, or produces free radicals within these cells, to prevent them from reproducing.

Radiation therapy for breast cancer is generally performed after surgical treatment or following chemotherapy after surgery, most commonly after lumpectomy. This helps to eliminate any lingering cancer cells, which helps to prevent breast cancer recurrence. Radiation therapy is performed in approximately one-half of breast cancer patients, according to the National Cancer Institute.

Radiation Therapy Planning for Breast Cancer

A breast cancer radiation therapy plan will vary significantly according to each individual patient’s condition. There are not only different types of breast cancer radiation therapy, but also different types of breast cancers. Radiation therapy also has potential to damage healthy cells, so it is especially critical that radiation therapy be carefully planned to minimize patient risk. Factors to consider in radiation therapy planning include:

  • Type of cancer.
  • Position of cancer in relation to healthy tissue.
  • Size of cancer.
  • Other treatments being administered for breast cancer and other health conditions.
  • Patient’s overall health, age and medical history.

Due to the numerous factors affecting radiation therapy, it is important that a breast cancer radiation therapy plan is made in collaboration with a multidisciplinary breast cancer treatment team. This team should include breast imaging specialists, breast-dedicated surgeons, medical oncologists and radiation oncologists.

Types of Breast Cancer Radiation Therapy

Radiation oncologists will work closely with other members of the multidisciplinary breast cancer treatment team. They also will consult and share information with the patient and her family to develop a breast cancer radiation therapy plan.

This plan will consider the results of multiple diagnostic tests and a thorough review of available health information to discuss the appropriate option for radiation therapy.

External beam radiation therapy

External beam radiation therapy is the most commonly used type of radiation therapy in breast cancer treatment. During external beam radiation therapy, a machine called a linear accelerator delivers photon beams (X-rays) to the location of cancer within the body.

Radiation is targeted precisely to avoid unnecessarily harming healthy tissue. This procedure is much like receiving an X-ray. External beam radiation therapy is generally given 5 days per week for 6 to 7 weeks.

3D-conformal radiation therapy

3D-conformal radiation therapy is a version of external beam radiation therapy that uses CT, MRI and/or PET/CT to more accurately target cancerous tissue. An even more advanced planning uses dose painting or field within a field to dose sculture around the area of interest while sparing critical structures.


Brachytherapy, also called internal radiation, is an alternative to external beam radiation therapy. This is used in Accelerated Partial Breast Irradiation (APBI) where a device is placed in the lumpectomy tumor bed by the breast surgeon. The catheters from the device are attached to High Dose Rate (HDR) equipment. The radioactive source travels thru the catheters to the device to deliver the radiation. The treatment is delivered twice a day, spaced 5-6 hours apart for 5 days, for a total for 10 fractions.

Breast Cancer Radiation Therapy Side Effects

Radiation therapy can cause side effects during treatment, as well as long-term side effects, although these will vary on a case-by-case basis. Some common side effects experienced by women undergoing breast cancer radiation therapy include:

  • Minimal Fatigue.
  • Chest or breast pain, minimal.
  • Skin reactions to radiation therapy.

A multidisciplinary breast cancer treatment team will consider possible side effects and discuss them with you prior to developing a treatment plan. There are also medications available to treat symptoms like skin dryness with moisturizing creams, as well as strategies you can employ to reduce the effect of radiation therapy side effects.

Orange County Radiation Oncology Center

Breastlink works with a range of radiation oncologists, including Orange County Radiation Oncology Center (OCROC). OCROC is a conveniently located in Santa Ana, California and plays a key role in Breastlink’s multidisciplinary breast cancer treatment team. OCROC’s breast cancer radiation team is led by Ernest Ngo, MD, FACRO and Chu-Pei Feng, MD, PhD.

Breast Cancer Radiation Therapy | radiation therapy for breast cancer

Orange County Radiation Oncology Center
1100 A N. Tustin Avenue
Santa Ana, CA 92705

Phone: 714.835.8520
Fax: 714.835.3610

Ernest Ngo, MD, FACRO

Dr. Ernest Ngo has conducted extensive research in the field of radiation oncology and has given numerous lectures to the medical community. He enjoys developing innovations to improve his patients’ treatments and meeting the challenges each cancer patient presents him with. He was one of the Pioneers in Orange County in the use of Stereotactic Radiosurgery (SRS) for brain tumors.

His patients have said, “you are knowledgeable in so many areas and you always make us laugh. We really enjoy coming here.” “Friendly, patient and caring. I very much am thankful to be in his care.” Those words define Dr. Ngo.

In his spare time Dr. Ngo enjoys spending time with his family, especially his wife, children, and grandchildren.  Other hobbies are auto racing, building model boats, gardening and ballroom dancing.

  • BOARD-CERTIFIED:  American board of Radiology (Therapeutic Radiology)
  • FELLOW: Fellow of the American Board of Radiation Oncology.(FACRO)
  • RESIDENCY: Radiation Medicine, Loma Linda University Medical Center.
  • INTERNSHIP (Radiology): White Memorial Medical Center, Los Angeles.
  • M.D.: Loma Linda University School of Medicine. Loma Linda, CA
  • BSc:  Chemistry and Premed:  University of California, Riverside, CA
    • MEMBER: ASTRO: American Society of Therapeutic Radiology and Oncology. ACRO:  American College of Radiation Oncology.
  • VOTED: One of Orange County’s “Top Doctors” by area physicians, Orange County Magazine, 2000.

Chu-Pei Feng, MD, PhD

  • Dr. Chu-Pei Feng is board-certified by the American Board of Radiology, Radiation Oncology.
  • Dr. Feng completed her residency and fellowship at John Hopkins University of Medicine, Baltimore.
  • She completed her PhD at the University of Maryland School of Medicine in Baltimore.

Radiation Therapy for Breast Cancer Consultation

If you would like more information about radiation therapy for breast cancer, or would like to schedule an appointment, please contact us.

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