Catching Ovarian Cancer Early May Miss Aggressive Tumors
TUESDAY March 24, 2009 -- Early-stage ovarian cancers may be slower growing and less likely to spread than the more aggressive forms typically found in advanced stages of the disease, researchers report.
The finding calls into question the effectiveness of ovarian cancer screening, the study authors say.
"Our study showed that the ovarian cancers currently detected at an early stage have gene expression profiles that correlate with favorable outcomes, rather than being representative of the entire spectrum of disease aggressiveness. This highlights the potential challenges of developing a screening test for this disease, because earlier detection of aggressive cases is essential if screening is to reduce ovarian cancer deaths," lead investigator Dr. Andrew Berchuck, a gynecologic oncologist at Duke Comprehensive Cancer Center, in Durham, N.C., said in a Duke news release.
He and his colleagues analyzed gene expression patterns in 166 ovarian cancer tissue samples, including advanced ovarian cancers from patients who lived more than seven years and from patients who died within three years of diagnosis. The analysis revealed genes associated with longer survival.
"We found that certain patterns predicted long-term survival, and others predicted a poor prognosis in advanced stage cases. Cancers that were detected at an early stage almost always shared gene expression characteristics with advanced stage cases that were long-term survivors, suggesting a shared favorable biology," Berchuck said.
The study was published in the March 24 issue of the journal Clinical Cancer Research.
"While these results could be seen as discouraging, it must be remembered that this information is an important piece of the ovarian cancer puzzle, and data like these that increase our understanding of the disease hopefully will eventually lead to breakthroughs in prevention, early detection and treatment of this deadly disease," Berchuck said.
Currently, there is no approved ovarian cancer screening test for the general population, but the CA125 blood test and transvaginal ultrasound imaging are being evaluated in clinical trials.
Posted: March 2009