SEOUL, South Korea -- While, overall, women with advanced stage lung cancer tend to live longer than men, the same is not true for premenopausal women, researchers found.
SEOUL, South Korea, Sept. 4 -- While, overall, women with advanced stage lung cancer tend to live longer than men, the same is not true for premenopausal women, researchers found.
Non-small-cell lung cancer survival was longest, at 11.6 months, for postmenopausal women, intermediate for men, and shortest, at 7.0 months, for premenopausal women younger than age 45 in pooled analysis of two large trials presented here at the International Association for the Study of Lung Cancer meeting.
The female survival advantage appeared to be primarily accounted for by women over age 60, which supports the role of estrogen in lung cancer, reported Heather A. Wakelee, M.D., of Stanford (Calif.) University, and colleagues.
"Consistently across stages, across studies, women live longer than men and here we have the younger women . . . doing worse than men," Dr. Wakelee said. "That's something that we really hadn't seen before."
"One of the big things that's been coming out in lung cancer is the estrogen story," she said. "At least in the lab it's been shown that estrogen can stimulate lung cancer growth."
So, the researchers looked to see if the differences in survival between women and men might be mediated by hormonal status as hypothesized in a prior observational study.
They analyzed data for 1,590 non-small-cell lung cancer patients from two Eastern Cooperate Oncology Group (ECOG) trials, excluding those treated with bevacizumab (Avastin) in one of the trials because of confounding factors.
There was no difference in prognostic factors across age and gender groups. The majority of participants were men (62%) and at least 60 years old (58.2%).
Median survival was significantly shorter among women younger than age 60, which was chosen as a cut-off age for menopausal status, than among older women (9.0 months versus 11.6, P=0.029).
For men, there was no significant difference between those younger than 60 or 60 and older (P=0.17).
When the researchers further stratified by age to separate out women who were clearly premenopausal, the difference was even more dramatic and showed opposite trends for men and women. The median survival findings were: