Boston - Women with early stage breast cancer who choose lumpectomy and radiation as their treatment option may be able to significantly shorten their total treatment time using three-dimensional conformal radiation therapy (3DCRT) according to new research from the Radiation Therapy Oncology Group (RTOG) presented at the American Society for Therapeutic Radiology and Oncology (ASTRO) 50th Annual Meeting in Boston. RTOG, an NCI-funded national clinical trials group, is a clinical research component of the American College of Radiology (ACR).

Breast conserving therapy of lumpectomy followed by radiotherapy, with its superior cosmetic result and equivalent survival outcome, is an accepted option instead of mastectomy for many patients with stage I or II breast cancer. A major drawback of standard breast conserving therapy is that it is a more complicated treatment regimen requiring five to seven weeks to complete radiotherapy. Using 3DCRT to more accurately target the radiation and spare uninvolved areas of the breast, RTOG researchers are able to deliver radiation to the tumor bed site in higher doses more quickly thus shortening the post lumpectomy treatment time to one week.

"These are very preliminary but encouraging results for women who need treatment but who also have families, careers and other factors to consider when deciding on breast conservation therapy for cancer," says Frank Vicini, M.D., chief of Oncology, Beaumont Hospitals, Royal Oak, MI. "We are leading a large, National Cancer Institute-sponsored clinical trial to give us more information on the benefits vs. risks of accelerated breast irradiation in one week compared to standard radiation therapy for up to seven weeks."

The phase II study, RTOG 0319, enrolled 58 women from 24 academic and community institutions in the United States and Canada from August 2003 until April 2004. The women enrolled on the study received 3DCRT twice daily, with each dose separated by six hours, for five consecutive days. Fifty-three of the patients were evaluable for efficacy reporting with a median follow-up of 4.0 years. At four years the disease-free survival rate was 84 percent, mastectomy-free survival was 90 percent, and overall survival was 96 percent. This is comparable to published rates for standard therapy.

"RTOG is able to test innovative treatment options such as accelerated partial breast irradiation with 3DCRT in a wide variety of treatment facilities both in the community and in academic centers. This allows us to respond to the needs of community physicians and moves proven, new therapies into general practice faster," said Walter J. Curran, Jr., the RTOG Group Chair, and the Lawrence W. Davis Professor and Chair of the Department of Radiation Oncology in the Emory School of Medicine and Chief Medical Officer of the Emory Winship Cancer Institute.

ASTRO Abstract #6, Initial Efficacy Results of RTOG 0319: Three Dimensional Conformal Radiation Therapy (3D-CRT) Confined to the Region of the Lumpectomy Cavity for Stage I/ II Breast Carcinoma, is available at http://www.redjournal.org/article/S0360-3016(08)00990-5/fulltext.

Information about RTOG is available at www.rtog.org.

In addition to Dr. Vicini, authors include: K. Winter, Radiation Therapy Oncology Group, Philadelphia, PA; J. Wong, Washington University of St. Louis, St. Louis, MO; H. Pass, John Hopkins, Baltimore, MD; R. Rabinovitch, New York Presbyterian Hospital, New York, NY; S. Chafe, Anschutz Cancer Pavilion, Aurora, CO; D. Arthur, Cross Cancer Institute, Edmonton, AB, Canada; I. Petersen, Medical College of Virginia, Richmond, VA; J. White, Mayo Clinic, Rochester, MN; and B. McCormick, Memorial Sloan Kettering Cancer Center, New York, NY. The research was funded by National Cancer Institute grants CA21661, CA37422, and 32115.

The Radiation Therapy Oncology Group (RTOG) is a clinical research enterprise of the American College of Radiology (ACR), located in the ACR Philadelphia, PA office. RTOG is a multi-institutional international clinical cooperative group funded primarily by National Cancer Institute grants CA21661, CA32115 and CA37422. RTOG has 40 years of experience in conducting clinical trials and is comprised of over 300 major research institutions in the United States, Canada, and internationally. The group currently is currently accruing to 40 studies that involve radiation therapy alone or in conjunction with surgery and/or chemotherapeutic drugs or which investigate quality of life issues and their effects on the cancer patient.

The American College of Radiology (ACR) is a national professional organization serving more than 32,000 radiologists, radiation oncologists, interventional radiologists and medical physicists with programs focusing on the practice of radiology and the delivery of comprehensive health care services.

Photo courtesy of Beaumont Hospitals