With state-of-the-art equipment and some of the field’s top experts, UCLA Health has emerged as a leader in an approach to radiation therapy that can reduce toxicity and length of treatment while offering potentially superior tumor control.
Unlike traditional radiation therapy, which sends wide beams of radiation to the entire tumor from a limited number of angles, TomoTherapy does its work slice-by-slice (tomographically) in a continuous fashion, operating like a computerized TomoTherapy (CT) scanner by rotating around the patient and providing radiation in a spiral delivery pattern. “By doing that, TomoTherapy is able to optimize the beam deliveries from all directions, increasing the precision,” explains Daniel Low, PhD, professor and vice chair of medical physics for UCLA’s Department of Radiation Oncology, who has contributed to the technology’s quality assurance innovations.
Before the advent of guided-image radiation therapy, radiation oncologists had no way to image the area being treated as the radiation beam was turned on, notes Patrick Kupelian, MD, professor of radiation oncology and the department’s vice chair of clinical operations and clinical research, as well as one of the earliest to use TomoTherapy clinically. “TomoTherapy was one of the first systems to integrate radiation delivery with an imaging device, so that you can be sure that you’re on target and make adjustments accordingly,” Dr. Kupelian explains.
The ability to more precisely target the radiation field in a way that avoids critical structures enables the radiation oncologist to deliver higher doses during each session, with the potential to shorten the sessions as well as the overall course of treatment.
“For prostate cancer, instead of seven to nine weeks of treatment, you might have one to two weeks,” says Dr. Kupelian. “It’s a tremendous convenience and much less of a burden for patients.”
The TomoTherapy system also facilitates so-called adaptive radiotherapy. The size and anatomical formation of tumors change during the course of radiation treatment. “TomoTherapy’s integrated imaging system acquires scans each day that not only help to position the patient, but also can be used to monitor the size and location of the tumor to determine if there needs to be adjustments in the treatment plan,” Dr. Low explains.
TomoTherapy is used at UCLA to treat a wide variety of cancers, but is particularly well suited for challenging cases involving large areas, or when the dose needs to be specially shaped to conform to the patient’s anatomy. These include head and neck cancers, lung cancers, abdominal and pelvic cancers, and gynecologic cancers. For cancers of the tongue, throat and larynx, TomoTherapy’s precise delivery can help to avoid damage to the salivary glands and side effects such as dry mouth and pain, notes Ke Sheng, PhD, who helped to develop the first TomoTherapy system at the University of Wisconsin and is now an associate professor of radiation oncology at UCLA. For cervical and endometrial cancers, he adds, TomoTherapy can protect the bowel, bladder and rectum and reduce the risk of troublesome side effects.