That's the conclusion of new research that found that women with early endometrial cancer who add radiation to their treatment can improve their odds of surviving longer.
"Endometrial cancer is the most common gynecological malignancy, and it's treated in a different fashion depending on which area of the country women live," said one of the study's authors, Dr. David Gaffney. He is an associate professor in the department of radiation oncology at Huntsman Cancer Hospital at the University of Utah Medical Center, Salt Lake City.
"There's been a great deal of controversy regarding radiation for stage 1, but in the appropriate subset of patients, a survival benefit was evident in our study," Gaffney added.
The study findings appear in the Jan. 25 issue of the Journal of the American Medical Association.
Each year, more than 40,000 U.S. women are diagnosed with endometrial cancer, according to the American Cancer Society. This type of cancer is often diagnosed at an early stage because irregular bleeding often signals its presence. Because it's usually diagnosed early, the five-year relative survival rate is already quite high -- about 90 percent, the society said.
To get that number even higher, researchers have been studying adding adjuvant therapies, such as radiation or chemotherapy, to surgical treatment for women with early endometrial cancer. However, because these therapies can have serious side effects, doctors need to know there's a clear benefit that outweighs the potential risks. But, the studies done to date have produced inconsistent findings.
In an attempt to learn if radiation therapy could provide an additional survival benefit to surgery for women with early endometrial cancer, Gaffney and his colleagues gathered data from the Surveillance, Epidemiology and End Results (SEER) cancer study, conducted between 1988 and 2001.
The database included 21,249 women with stage 1 endometrial cancer. Stage 1 means the cancer is confined to the uterus and hasn't spread to other areas. About 75 percent of women are diagnosed at this stage, according to the National Comprehensive Cancer Network. Staging also includes a letter grade between A and C, which indicates how far into the uterine lining the cancer has progressed, with C indicating the deepest penetration. In addition to being "staged," tumors are also given a grade, and the higher the grade, the more aggressive the cancer is likely to be, according to Gaffney.
The women averaged just over 63 years of age at the time of diagnosis.
Nearly 20 percent of these women -- 4,080 -- received adjuvant radiation therapy. The remaining women did not.
The researchers found the biggest benefit from adjuvant radiation for women with stage 1C endometrial cancer. In women under 56 years old with stage 1C, grade 1 cancer, the five-year overall survival rate was 98 percent for women who received adjuvant radiation and 88 percent for women who didn't. In the 56- to-75-year age group, those numbers were 94 percent versus 85 percent, respectively. In the over 75 group, the rates were 84 percent compared to 67 percent, respectively.
For women in the under-56 age group with higher grade cancer -- grades 3 or 4 -- the five-year overall survival rate was 86 percent for those who received radiation therapy, versus 77 percent for those who didn't. For older women, those between 56 and 75, those numbers were 66 percent versus 56 percent. For those older than 75, the survival rates were 53 percent versus 39 percent, respectively.
"This study strongly suggests that for women [with stage 1C] cancer, radiation is something to strongly consider," said Dr. Len Lichtenfeld, the deputy chief medical officer for the American Cancer Society. "When the disease is confined to the uterus, but more advanced, adjuvant radiation therapy does have a benefit."
That doesn't mean the therapy is without its drawbacks, however, Lichtenfeld said. Radiation therapy can have serious side effects, and women need to work with their doctors to come up with a treatment plan they're comfortable with, he added.
"There's no one-size fits all treatment," Lichtenfeld said.
More information
You can learn more about endometrial cancer from the American Cancer Society.
