Prone positioning for breast radiation treatment

The USC Norris Comprehensive Cancer Center at Keck Medicine of USC is offering prone-position radiation treatment for patients with early stage breast cancer through Jason Ye, MD, assistant professor of clinical radiation oncology at the Keck School of Medicine of USC.

By allowing gravity to pull the breast tissue away from the chest wall, the prone, or face down, position, consistently reduces, if not eliminates, the inclusion of the heart and lung within the radiation field. In the traditional supine position with the patient lying on her back, gravity pulls the breast closer to the body, potentially leading to radiation exposure of internal organs.

In the early 1990s, doctors at USC led by Silvia Formenti, MD were at the forefront of exploring the prone position for radiation treatment. Ye learned the technique from Formenti while performing his residency at Weill Cornell Medical College, where she is now chair of the department of radiation oncology.

The prone radiotherapy of the breast that Ye brought back to Keck Medicine is more advanced than what Formenti pioneered previously at the school.

At Norris, Ye has access to specialized equipment to employ the technique better than ever before. In addition to a prone breast board, the treatment machine captures cone beam computed tomography images that are 3D-matched with a CT scan taken earlier to know precisely where to target.

“The way most places do this verification, whether supine or prone, is through a plain x-ray, so you don't really see what's going on inside the body,” Ye said.

Norris is one of the few sites in Southern California that offers the approach with this technology.

Radiation oncologists aren't typically trained in the prone position. They are used to working in the supine, where they can see how the beam hits the skin. Most sites also do not have the specialized equipment needed, which Ye said is why only about 10 percent of radiation oncology practices use the technique.