BOSTON, Oct. 29, 2012 (GLOBE NEWSWIRE) -- Elderly women with early-stage breast cancer who received adjuvant radiation therapy after lumpectomy surgery have improved cause-specific survival (CSS) compared to those patients who underwent surgery alone, according to research presented today at the American Society for Radiation Oncology's (ASTRO's) 54th Annual Meeting. Additionally, the data suggests that patients who have a life expectancy of at least 10 years after diagnosis and treatment benefit in local tumor control and in overall survival if they receive adjuvant radiation therapy.
This study evaluated the records of 29,949* women (*updated data) from the Surveillance, Epidemiology and End Results (SEER) database between 1990 and 2008, ages 70 to 84, diagnosed with clinical stage I, estrogen receptor positive (ER+) breast cancer who underwent lumpectomy with or without adjuvant radiotherapy and who survived at least one year after initial diagnosis. Seventy six percent of the patients (22,781) received adjuvant radiation treatment. The median survival was 13.1 years for patients treated with surgery and radiation and 11.1 years for patients receiving surgery alone. CSS after five years was statistically significant at 98.3 percent for patients who received adjuvant radiation treatment compared to 97.6 percent of patients who received surgery alone. After 10 years, CSS was 95.4 percent for patients who received adjuvant radiation compared to 94.3 percent of patients who received surgery alone. At five, 10 and 15 years, the overall survival (OS) of patients was 89.5 percent, 66.8 percent and 40.8 percent, respectively, for those treated with surgery and radiation, compared to 83.0 percent, 56.1 percent and 30.2 percent for those treated with surgery alone. The Kaplan-Meier method was used to calculate CSS and OS. As women aged, the use of radiation therapy decreased?accounting for 80 percent of women aged 70-74, 74 percent of women aged 75-79 and 61 percent of women aged 80-84.
This study furthered results of a previous Cancer and Leukemia Group B (CALGB) study that examined the addition of radiation to lumpectomy and tamoxifen in women age 70 and older with clinical stage I, ER+ breast cancer. The CALGB study included 636 patients; 317 patients, or almost 50 percent, were treated with adjuvant radiation therapy. The study concluded an absolute reduction of six percent in ipsilateral breast tumor recurrence with the use of radiation at a median follow-up of 10.5 years, but there was no improvement in CSS or OS.
"Our study reviewed a large population and found that elderly women with early-stage breast cancer who were treated with adjuvant radiation after surgery had an improvement of their breast cancer survival rate, which suggests that radiation, for appropriate elderly women, should be strongly considered as part of their treatment plan," said Randi J. Cohen, MD, lead author of the study and a radiation oncologist at the University of Maryland in Baltimore. "A woman's age alone should not impact whether or not radiation treatment is presented as a viable treatment option."
The abstract, "Improved Survival with Adjuvant Radiation in Elderly Women with Early-Stage Breast Cancer," will be presented in detail during a scientific session at ASTRO's 2012 Annual Meeting at 11:00 a.m. Eastern time on October 29, 2012. To speak with Dr. Cohen, call Michelle Kirkwood on October 28 – 31, 2012, in the ASTRO Press Office at the Boston Convention and Exhibition Center at 617-954-3461 or 617-954-3462, or email michellek@astro.org.
ASTRO's 54th Annual Meeting, held in Boston, October 28 – 31, 2012, is the premier scientific meeting in radiation oncology and brings together more than 11,000 attendees including oncologists from all disciplines, medical physicists, dosimetrists, radiation therapists, radiation oncology nurses and nurse practitioners, biologists, physician assistants, practice administrators, industry representatives and other health care professionals from around the world. The theme of the 2012 Annual Meeting is "Advancing Patient Care through Innovation" and examines how innovation in technology and patient care delivery can lead to improved patient outcomes. The four-day scientific meeting includes six plenary papers and 410 oral presentations in 63 oral scientific sessions, and 1,724 posters and 130 digital posters in 18 tracks/topic areas.
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ASTRO is the largest radiation oncology society in the world, with more than 10,000 members who specialize in treating patients with radiation therapies. As the leading organization in radiation oncology, biology and physics, the Society is dedicated to improving patient care through education, clinical practice, advancement of science and advocacy. For more information on radiation therapy, visit www.rtanswers.org. To learn more about ASTRO, visit www.astro.org.
2012 American Society for Radiation Oncology (ASTRO) 54th Annual Meeting
News Briefing, Tuesday, October 30, 7:00 a.m. – 7:45 a.m. Eastern time
Scientific Session: October 29, 2012, 11:00 a.m. – 12:30 p.m. Eastern time, Boston Convention & Exhibition Center
82 Improved Survival with Adjuvant Radiation in Elderly Women with Early-Stage Breast Cancer
R. J. Cohen1, L. Li2, W. Citron1, M. Oh1, C. Drogula1, S. Cheston1, C. Bui1, S. J. Feigenberg1, 1University of Maryland, Baltimore, MD, 2Bryn Mawr Hospital, Bryn Mawr, PA
Purpose/Objective(s): The Cancer and Leukemia Group B (CALGB) studied the addition of radiation to lumpectomy and tamoxifen in women age 70 and older with clinical stage I, estrogen receptor positive (ER+) breast cancer. At a median follow-up of 10.5 years, there was an absolute reduction of 6% in ipsilateral breast tumor recurrence with the use of radiation, but there was no improvement in overall survival (OS) or cause specific survival (CSS). The purpose of this study was to evaluate survival outcomes of elderly women with ER+, early stage breast cancer treated with lumpectomy and radiation versus lumpectomy alone using a large, population-based database.
Materials/Methods: The Surveillance, Epidemiology, and End Results (SEER) database was utilized to obtain data for all women ages 70 to 84 years old diagnosed with T1 N0 M0, ER+, breast cancer between 1990 and 2008 who underwent lumpectomy with or without adjuvant radiotherapy. The Kaplan-Meier method was used to calculate OS and CSS.
Results: 29,127 women who survived at least one year following initial breast cancer diagnosis were identified. Median follow-up was 10 years. 50% of patients received adjuvant radiation. With increasing age, the use of adjuvant radiation decreased with 55% of women age 70-74, 50% of women 75-79, and 40% of women 80-84 years old receiving external beam radiation. At 5 years, CSS was 97.6% (95% confidence interval, CI: 97.3%-97.8%) for surgery alone versus 98.3% (95% CI: 94.9%-95.8%) for adjuvant radiation. The improvement in CSS with the addition of radiation persisted at 10 years: 94.3% (95% CI: 93.8%-94.8%) versus 95.4% (95% CI: 94.9%-95.8%), (p less than 0.05). The median survival was 11.1 years for patients receiving surgery alone and 13.1 years for surgery and radiation. The OS was significantly better at all time points for women receiving radiation. At 5, 10, and 15 years, the OS was 83.0%, 56.1%, and 30.2% for those treated with surgery alone compared to 89.5%, 66.8%, and 40.8% treated with surgery and radiation (p less than 0.05).
Conclusions: Elderly women with early stage breast cancer treated with surgery and adjuvant radiation have improved outcomes compared to those treated with surgery alone, likely related to an improvement in locoregional control. The patients selected for radiation were likely healthier with longer anticipated life expectancy. However, even in the surgery alone patients, median survival was 11.1 years. Although information regarding hormonal therapy usage is not available, the improvement in CSS with the addition of radiation suggests that in healthy, elderly women, adjuvant radiation should be strongly considered as part of their breast cancer treatment.
Author Disclosure Block: R.J. Cohen: None. L. Li: None. W. Citron: None. M. Oh: None. C. Drogula: None. S. Cheston: None. C. Bui: None. S.J. Feigenberg: None.