Radiation Therapy for Breast Cancer: A Guide to the Latest Technology

Quick summary

Advances in radiation therapy offer many new treatment choices for breast cancer. When the oncologist recommends radiation, be sure to check whether the type of radiation she suggests is the most advanced strategy available for this particular breast cancer.

Pushing for the right radiation therapy treatment

After the oncologist recommends a course of treatment for breast cancer that includes radiation therapy , you're naturally going to have many questions. Among them will be concerns about whether the type of radiation the doctor's recommending is the most advanced and aggressive strategy available.

"Not all radiation therapy is created equal," says oncologist Shalom Kalnicki, chairman of radiation oncology at Montefiore Medical Center and the Albert Einstein College of Medicine in New York. "You want to understand what's involved and find out about all the options, so you can make the best choice."

For suggestions on what to ask during this important discussion, see 15 Questions to Ask About Radiation Therapy for Breast Cancer . Certainly, the oncologist knows more about breast cancer than you do and may have solid reasons for recommending a particular treatment -- but it's also possible she's recommending only the treatment available in the hospitals she's affiliated with. To prepare for this talk, you'll want to know the terms for the wide variety of techniques available. Here's a rundown of the newest radiation technologies:

3-D conformal radiation therapy (3D-CRT)

Probably the most common form of standard radiation used today is conformal radiation, in which doctors use computer technology to map the tumor with imaging techniques s uch as MRIs and PET scans. This allows doctors to target the radiation beam to more closely match the shape of the tumor. Scans cover the tumor's width, height, and depth -- hence the term 3-D.

IMRT (intensity-modulated radiation therapy)

IMRT has gradually become the standard of care for many types of cancers, particularly cancers of the head and neck, lung, abdomen, and pelvis, for which precision in delivering radiation is important. But it's also starting to be used in breast cancer treatment, particularly in patients who've had standard radiation therapy and have recurrent tumors. Here are some basics to know about IMRT:

  • It delivers precise, strong radiation. IMRT uses a linear accelerator to deliver thousands of precisely focused small beams of radiation that follow the exact contours of a tumor, allowing the radiation oncologist to target the tumor much more exactly while damaging less of the surrounding tissue. Because surrounding tissue is better protected, the radiation dosages delivered via IMRT can also be higher, resulting in more effective treatment.
  • It's not available everywhere. Unfortunately, because it uses different machinery than standard radiation therapy, IMRT is not available in all hospitals. If you ultimately decide that this is the treatment you want, you may have to ask her doctor whether you -- or the person you're caring for -- should seek treatment at another hospital or cancer center. It may be worth fighting for, however: The studies are impressive, and many experts advocate a switch to IMRT for the treatment of some breast tumors.

Image-guided IMRT (IG-IMRT, or IGRT)

  • It delivers more easily adjusted radiation. This even more advanced form of IMRT uses online computer imaging to adapt radiation therapy to the changing contours of the tumor in real time, during the radiation therapy itself. (In regular IMRT, the mapping is usually done ahead of time.) The computer compares images taken before the procedure to those taken during the procedure its elf. Since tumors typically shrink as a result of radiation therapy, IG-IMRT (also called IGRT) allows doctors to adjust the radiation to accommodate the shrinking tumor margins, protecting the growing area of healthy tissue around the edge.
  • It's good for delicate locations. Also called image-guided adoptive planning, IG-IMRT has been used with great effectiveness to treat tumors in delicate, complex locations such as the head and neck. Study results show that IG-IMRT allows doctors to use high doses of radiation with less damage to healthy tissue.

Helical tomotherapy

Another type of IMRT, this technique uses a large linear accelerator inside a doughnut-shaped contraption that spirals around the body during treatment, delivering beams of radiation from many angles. Advocates believe this technique, also called a spiral CT scan, allows even more precisely focused radiation. It's also sometimes used as a screening technique.

Respiratory gated radiation therapy

Because radiation therapy requires such precise targeting, even the tiny movements caused by breathing, swallowing, and blood flow can throw off the radiation beams and lead to tissue damage. To solve this problem, respiratory gated treatment employs computer imaging to map radiation treatment, so that the dose of radiation is modified to accommodate changes in the shape of the tumor caused by the patient's breathing or swallowing. (Without respiratory gating, doctors typically radiate the entire area that the tumor moves through as the patient breathes, which causes radiation to be delivered to healthy tissu e.)

Sometimes called target motion management, this brand-new therapy increases the success of treatment for tumors in the breast near the lung or heart.

Stereotactic radiosurgery

Used almost exclusively for brain tumors, this technique aims a very high-dose radiation beam at a small area during a single session. It's the dramatic procedure you see on hospital shows during which the patient's head is enclosed inside a frame to hold it still. A related technique, stereotactic radiotherapy, uses smaller, fractional doses of radiation given multiple times. This type of surgery would only be used in a breast cancer patient whose cancer had spread to the brain.

Melanie Haiken

Melanie Haiken discovered how important it is to provide accurate, targeted, usable health information to people facing difficult decisions when she was health editor of Parenting magazine. See full bio