Feature: Intraoperative breast RT in practice
In June 2010, the TARGIT (Targeted Intraoperative radiation Therapy)Trial confirmed that delivering radiation at the time of lumpectomy was as effective in preventing breast cancer recurrence as whole breast radiation therapy in selected patients. Since January, radiation oncologists and surgical oncologists at Northwestern Memorial Hospital have paired up to offer the new protocol to women at low-risk, primarily older patients with T1 lesions.
The treatment provides a full dose of radiation therapy during breast-conserving surgery, combining both radiation therapy and lumpectomy and the radiation course during a two-hour operation. The treatment delivery device is placed directly into the lumpectomy cavity, so radiotherapy can be directed to the part of the breast where the cancer was, while sparing the rest of the breast, chest and shoulder from the effects of radiation.
“With this technique, the radiation oncologist will be in the operating room administering radiation to the tumor bed immediately following the surgeon’s removal of the tumor,” explained William Small, Jr., MD, vice chairman of radiation oncology at Northwestern Memorial Hospital and professor of radiation oncology at Northwestern University Feinberg School of Medicine.
The model re-invents the conventional process of lumpectomy followed by a six-week course of radiation therapy, making it more convenient for women. Plus, as Small explained, “Treatment planning is very different from conventional planning.”
The streamlined intraoperative protocol eliminates CT-based treatment planning. Instead, the radiation oncologist uses intraoperative ultrasound to localize the target and then applies the entire radiation dose.
Although the workflow is simplified, the protocol requires a philosophical shift on the part of radiation oncologists, Small noted, because radiation oncologists must meet with patients prior to surgery.
The simplified treatment planning is paralleled by simplified treatment for patients. The conventional six-week schedule can be challenging for women who have busy schedules or do not have access to a center offering radiation therapy. In some cases, the six-week schedule causes women to not comply with the recommended course of treatment, increasing their risk for cancer recurrence.
Intraoperative radiation therapy employs the same follow-up process as conventional treatment. However, because pathological results are typically not available at the time of treatment, patients whose pathology results reveal features conducive to a higher recurrence risk may undergo additional surgery or external beam radiotherapy.
Currently, only women with early stage breast cancer are considered candidates for intraoperative radiation therapy.
“This isn’t a replacement for traditional breast cancer treatment, but for the right candidate it may be an attractive alternative,” said Small. “This has potential to expand access to radiation therapy, allowing more women to comply with the recommended course of treatment. Hopefully, with a more concise and convenient treatment available, a broader group of women will have the option to choose breast-conserving treatment options.”