Dennis Holmes
If USC cancer specialists have their way, certain women with early-stage invasive breast cancer will be able to receive their entire course of radiation therapy in a single treatment – while still under anesthesia after surgery.
USC/Norris Comprehensive Cancer Center is participating in an international, multi-center clinical trial of intraoperative radiotherapy, a technique aimed at women who undergo lumpectomy – a minimally invasive, breast-conserving surgery. Initial European studies indicate intraoperative therapy has similar side effects and effectiveness as external-beam radiation.USC breast surgeon Dennis R. Holmes calls the new technique “a tremendous advancement” both in terms of improved breast-cancer treatment and reduced disruption to patients’ lives.
Ordinarily, when physicians find invasive breast cancer early – and women have a single, small tumor and no sign of cancer spread to the lymph nodes – there’s no need for a mastectomy. The cancer may be effectively treated by lumpectomy with follow-up radiation therapy.
But traditional radiation therapy requires that patients visit a medical center five days a week for six to seven weeks. Some women find this so disruptive to their lives that they opt for the more invasive mastectomy rather than undergo weeks of radiation.
“With intraoperative radiotherapy, radiation is administered during the surgical procedure, avoiding the need to return for additional radiotherapy later,” says Holmes, a clinical surgeon in the Keck School of Medicine of USC and principal investigator in the intraoperative radio-therapy trial at USC/Norris. “It only takes 20 to 35 minutes to administer, after the tumor has been removed.”
The new technique involves a special gold-tipped wand attached to the arm of a machine called Intrabeam. While the patient is still under anesthesia, physicians maneuver and manipulate this wand inside the cavity left by the removed tumor. The device accelerates electrons and shoots them through the gold tip, emitting X-rays exactly where they are needed: in the tissues immediately surrounding the tumor, where the risk of cancer recurrence is greatest.
Surgeons then close the incision, and pathologists check the tumor’s margins to ensure its full removal.