Estrogen May Improve Colon Cancer Survival
Younger Women With Advanced Disease Live Longer
By
Salynn Boyles
WebMD Health News
Reviewed By
Louise Chang, MD
Sept. 29, 2009 -- Younger women with advanced colon cancer live slightly
longer than younger men with advanced disease, but the survival advantage
disappears as women age and their estrogen levels drop, a new study shows.
Previous research suggests a role for the female hormone in protecting
against colorectal cancer. Women are less likely than men to get the disease,
and they tend to be diagnosed later in life.
The new study is the first to suggest that estrogen also improves outcomes
in premenopausal women and that it may help cancer treatments work better,
researcher Heinz-Josef Lenz, MD, of the University of Southern California tells
WebMD.
"Young women seem to be benefiting more from the latest, aggressive
treatments for colorectal cancer than young men are," says Lenz, who co-directs
the colorectal cancer center at USC's Norris Comprehensive Cancer Center/Keck
School of Medicine.
Estrogen May Help Chemo Work
About 150,000 new cases of colon or rectal cancer will be diagnosed in the
United States this year, and nine out of 10 cases will occur in people over the
age of 50, according to the American Cancer Society (ACS).
When younger adults do get colorectal cancer, some studies suggest the
disease may be more aggressive.
In the newly published research, Lenz and colleagues analyzed data from a
large national cancer registry that included about 53,000 patients with
advanced colorectal cancer who were diagnosed and treated between 1988 and
2004.
On average, women younger than age 45 lived longer than men of the same age
-- 17 months vs. 14 months.
Survival times were about equal for women and men between the ages of 45 and
54. But as a group, older women (55 years and older) with cancer that had
spread beyond the colon or rectum had a shorter survival than men -- seven
months vs. nine months.
The survival advantage among young women was seen in all ethnic groups, and
the gender disparity was greatest among younger patients treated after
1999.
The study appears in the Oct. 15 issue of the journal Clinical Cancer
Research.
"Up until eight or nine years ago we had only one drug (5-fluorouracil) to
treat colorectal cancer," Lenz says. "Now we have many more treatment options
and this research suggests that young women benefit more from these drugs than
men."
'Too Soon to Recommend Estrogen'
It is not clear exactly how estrogen protects against colorectal cancer. One
theory points to a protein called estrogen receptor beta that helps estrogen
work.
As women age and their estrogen production drops, they also produce less
estrogen receptor beta. This loss is emerging as an important step in the
progression of hormone-dependent tumors, the researchers write.
American Cancer Society Director of Prostate and Colorectal Cancers Durado
Brooks, MD, calls the study "intriguing," but he says its relevance for
colorectal treatment remains to be determined.
"I can certainly see where some investigator might want to look at whether
adding estrogen to chemotherapy in men and older women with colorectal cancer
might make a difference in survival," he says. "But it is way too early to
recommend that as a treatment strategy."
There are also suggestions from several recent studies that hormone
replacement therapy lowers a woman's risk for developing colorectal cancer
after menopause.
But this potential benefit has to be weighed against the increased risk for
breast cancer and certain risk factors for heart disease associated with hormone therapy, Brooks says.
SOURCES: Hendifar, A. Clinical Cancer Research, Oct. 15, 2009; vol 15: online edition.
Heinz-Josef Lenz, MD, associate professor of medicine; co-director of gastrointestinal oncology and colorectal cancer, University of Southern California/Norris Comprehensive Cancer Center, Keck School of Medicine, Los Angeles.
Durado Brooks, MD, director of prostate and colorectal cancers, American Heart Association.
American Cancer Society: "Detailed Guide: Colon and Rectum Cancer.
News release, American Association for Cancer Research.
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