New Techniques for Delivering Radiation Therapy During Cancer Surgery

Columbia’s radiation oncologists and surgeons are treating a growing number of patients using an innovative radiation therapy at the time of surgery. By delivering a single, concentrated dose of radiation to the cavity where a cancerous tumor has just been removed, intraoperative radiation therapy—IORT—can reduce the risk of cancer recurrence, can preserve healthy tissue, and may eliminate the need for postoperative external beam radiation. 

NYP/Columbia in 2013 became one of the first hospitals in the New York metropolitan area to offer IORT to patients diagnosed with early-stage breast cancer. 

During an IORT procedure, a radiotherapy applicator is placed directly in the tumor bed, targeting the area that has the highest risk of tumor recurrence and helping to destroy any cancer cells that might have been left behind.

Conventional therapy for early-stage breast cancer involves three and a half weeks of external beam radiation after surgery. But data from two randomized trials suggest that in well-selected patients, IORT is as effective as conventional radiation treatment in reducing the risk of local cancer recurrence. The best candidates for IORT are postmenopausal women undergoing a lumpectomy to remove a single tumor that is less than three centimeters in size. 

Physicians recommend that patients receive additional postoperative radiation treatments if the final pathology report shows that the cancer spread to the lymph nodes or is particularly aggressive, such as triple-negative breast cancer. But 85 percent of those who receive IORT can forgo postoperative radiation treatments and avoid the related side effects such as a sunburn-like skin reaction and fatigue. 

The convenience of IORT is especially important to some patients. “About a third of the patients we treat with IORT are elderly women who would otherwise skip radiation, because traveling to the hospital every day for several weeks would have been too difficult,” says Eileen P. Connolly, MD, PhD, assistant professor of radiation oncology at CUMC.

Dr. Connolly and her team are soon launching a study to see if other women—younger patients who have not started menopause and those who have triple-negative breast cancer—may benefit from IORT plus conventional radiation therapy after surgery.

Last year, NYP/Columbia also started offering IORT for other types of cancer in the abdomen and pelvis. 

“When we use IORT for tumors in the abdomen or pelvis, our goal is to maximize the therapy the patient is receiving and reduce the risk of recurrence as much as possible,” says David P. Horowitz, MD, assistant professor of radiation oncology at CUMC. “We’re not necessarily trying to eliminate a course of radiation therapy the way we do with the early-stage breast cancer patients.”

A key advantage of IORT is that it allows physicians to focus a higher dose of radiation on the tumor site while sparing the surrounding tissues in the abdomen and pelvis. Patients also tolerate the treatment well and it does not extend the surgery recovery time.