Oncology Practice Pioneers Cancer Treatment

An oncology practice in the Diablo Valley is a pioneer in performing a new, more convenient, less expensive radiation therapy for women at an early stage of breast cancer.

Diablo Valley Oncology — with offices in Pleasant Hill, Walnut Creek, San Ramon and Brentwood — is the first practice in the East Bay offering IORT (Intraoperative Radiation Treatment), according to a Diablo Valley Oncology news release.

The practice performed the outpatient treatment twice in December at the Aspen Surgery Center (located next to John Muir Medical Center in Walnut Creek), and is ready to do more in coming months, said Dr. Sachin Kamath, a radiation oncologist with Diablo Valley. IORT with portable equipment allows localized radiation treatment at the time of the lumpectomy, while the tissue is opened up for the surgeon, rather than the more traditional procedure of multiple radiation treatments in the weeks after the operation.

"Radiation therapy is a critical element of breast cancer treatment," said Kamath. "However, historically it has required several weeks of daily treatments, which can pose a financial and logistical challenge for some patients. The Xoft eBx System gives us the ability to provide the necessary radiation treatment at the time of surgery and is less disruptive and less burdensome on the patient's lifestyle." Xoft is the Sunnyvale company that makes the equipment for IORT.

The electronic brachytherapy technology for IORT uses a miniaturized X-ray tube inside a wand-like applicator that delivers radiation at very close range to the tumor bed of a patient at the time of a lumpectomy. It minimizes radiation exposure to healthy tissue. It administers radiation to get cancer cells in hard-to-reach crevices in the tissue, Kamath said.

Older existing technologies require the use of heavier equipment such as a linear accelerator or a live radioisotope-based machine — both of which require expensive radiation-shielded rooms — with daily treatments over a period of several days to weeks. The Xoft machine requires no special shielding because it uses electronics with on-off switches, enabling safer, more accurate control of radiation delivery to the target tissue, Kamath said.

During IORT, the radiation is evenly distributed in the area of the lumpectomy cavity. The radiation is administered through a saline-filled balloon placed in the cavity for eight to 10 minutes. After the radiation treatment, the incision is closed and the patient monitored in the recovery room for a couple of hours before going home, Kamath said. The one-time outpatient procedure saves money for insurance companies and Medicare compared to the more expensive treatments that extend over several days or weeks, he said.

IORT using the balloon targets radiation to the lumpectomy bed, instead of a more general application of radiation to the whole breast in  the older treatments in use, Kamath said.

The right cases

The procedure is for early stage breast cancer — about one-quarter of cases, Kamath said. Some candidates are eliminated because of anatomical reasons. Surgeons and oncologists work together to pick the right cases.

"The bottom line is that we need to catch more of these cancers in earlier stages," said Kamath.

Diablo Valley Oncology decided to pursue IORT after about five years of promising results from a randomized trial that included treatments at Stanford and the University of California at San Francisco, said Kamath.

Because of the shorter duration of treatment, it could be that Diablo Valley Oncology will become a regional hub for this procedure, Kamath said.