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T HE TARGIT TRIAL examined the merits of risk-adapted, single-dose, targeted intraoperative radio- therapy compared with external whole-breast radiotherapy. The ELIOT trial compared the effectiveness of single-dose intraoperative electron radiotherapy with that of external radiotherapy. "The goal of research projects like these is to develop shorter courses of therapy that are equally effective and have good cosmetic results, lower side effects and lower treatment costs," says Len Lichtenfeld, MD, Deputy Chief Medical Offi cer of the American Cancer Society. Methods Though both studies examined the efficacy of single-dose radiation, they differed in administration of these alternate therapies and in results. The TARGIT trial was risk-adapted, highlighting the potential to use single-dose radiation therapy as part of a structured treatment plan. Patients were randomly assigned to one of three groups, in which they received TARGIT during the lumpectomy procedure, TARGIT in a secondary procedure postoperatively when pathology identifi ed nonaggressive cancers, or traditional external beam radiation therapy (EBRT). (Patients with aggressive cancers automatically received EBRT.) The ELIOT trial assigned patients randomly to one group or the other, clearly defining it as a test of internal versus external radiation therapy. Findings After fi ve years, 2.1 percent of patients who received TARGIT therapy during lumpectomy had disease recurrence, compared with 1.1 percent of those who underwent EBRT. Though the rate of recurrent cancer was slightly higher in TARGIT patients, researchers considered it comparable within the study's error margin. Those who received TARGIT during a second procedure had a higher recurrence rate of 2.5 percent. Even with higher recurrence, overall mortality after fi ve years and mortality due to non-breast-cancer-related causes were lower in TARGIT patients, as were high-grade skin complications from radiation therapy. In the ELIOT trial, overall survival rates between the two groups were simi- lar, but recurring breast cancer rates were not. After fi ve years, breast cancer recurred in 4.4 percent of patients who underwent intraoperative radiotherapy, compared with 0.4 percent in the external radiotherapy group. Challenges One of the limitations of the TARGIT trial was patient selection. Though the trial allowed patients with tumors up to 3.5 centimeters in diameter to participate, clinician discretion led to the average diameter of participants' tumors being less than 2 centimeters, making it dif- ficult to apply the results to all breast cancer patients. Just 1,305 patients participated in the ELIOT trial — a relatively small sample size, especially when compared with the 3,451 who participated in the TARGIT trial. Despite these limitations, offering a single-dose course of radiation at the time of lumpectomy does address the time, ability and fi nancial constraints thought to lead many patients to halt courses of postopera- tive radiation therapy. While they may not represent options for all breast cancer patients, these two trials put researchers one step closer to realizing the full potential of single-dose concentrated radiation therapy in lumpectomy patients. ■ POSTOPERATIVE RADIATION THERAPY IS THE STANDARD OF CARE FOR BREAST CANCER PATIENTS WHO UNDERGO LUMPECTOMY. TWO RECENT CLINICAL TRIALS LOOK AT ALTERNATIVE OPTIONS. Examining Merits of Single-site Radiation Therapy in Lumpectomy Patients By Valerie Lauer CORE SPECIAL CLINICAL SECTION: IMAGING 2 2 | Long Island MD NEWS ■ M D N E W S . CO M