Endometrial cancer remains the most common gynecological malignancy in the United States, according to background information in the article. However, the optimal supplemental treatment for stage I endometrial cancer remains uncertain.
Christopher M. Lee, M.D., of Huntsman Cancer Hospital and University of Utah Medical Center, Salt Lake City and colleagues conducted a study to quantitatively evaluate the frequency and effect of adjuvant (supplemental) radiation therapy (RT) on overall and relative survival for women with stage I endometrial cancer. The study included 21,249 patients with American Joint Committee on Cancer stage IA-C node-negative endometrial cancer. The researchers used data from the Surveillance, Epidemiology, and End Results Program of the U.S. National Cancer Institute, from January 1, 1988, to December 31, 2001.
Of the 21,249 women, 4,080 received adjuvant RT (19.2 percent) and 17,169 did not receive adjuvant RT (80.8 percent). Adjuvant RT significantly improved overall survival for patients with stage IC/grade 1 and stage IC/grades 3 and 4 disease. Further analysis revealed a statistically detectable association of adjuvant RT with improved relative survival in patients with stage IC/grade 1 (56 percent lower rate of death) and stage IC/grades 3 and 4 (28 percent lower rate of death).
"As the largest reported population analysis to our knowledge of adjuvant RT in early stage endometrial adenocarcinoma to date, it is significant that our study reveals a benefit for improved overall and relative survival for adjuvant RT in stage IC/grade 1 and stage IC/grades 3 and 4 disease. This information should be added to previous articles in the literature that confirm beneficial effects of adjuvant RT on both local and distant tumor control for certain patient cohorts," the authors write.
"Statistical analysis cannot replace clinical judgment when considering the individual patient, tumor characteristics, and the potential risks and benefits of adjuvant RT. Hopefully, appropriate adjuvant RT will be used to decrease the death rate from this most common of gynecological malignancies. Future work is needed to continue to delineate clinical and biological factors that can guide treatment and account for disparities in outcome between varied subsets of patients," the researchers conclude.
(JAMA. 2006;295:389-397. Available pre-embargo to the media at www.jamamedia.org)
Editor's Note: This study was supported in part by a grant from the Cancer Center Support.