Study shows tougher fight for young breast cancer victims

By Helen Chickering, NBC Medical Reporter  

LOUISVILLE (WAVE) - The pink ribbon disease may soon be wearing a new color, or at least a different shade of pink. Breast cancer researchers have made an important discovery about how the disease behaves in younger women, specifically why it is often so much deadlier. Until now, doctors had few clues other than family history, or the thinking that younger women are often diagnosed late. But new findings suggest the tumors in younger women have a unique set of personality traits - and they are anything but pastel.

34 year old Corinna Proctor divides her days between the office, and the hospital battling breast cancer.

"It came out of left field and I didn't expect it at all," says Corinna.

Women under 40 account for only 5% of breast cancer cases, but when it strikes, the disease is often more aggressive.

"For many, many years, we said, 'Well because they were unfortunate to get breast cancer', and that's a bad thing," says Dr. Kim Blackwell, a cancer researcher at Duke University Medical Center.

Now, researchers are figuring out why.

"We found in our study there were things in young women's tumors tick that make them unique," Dr. Blackwell says.

The unique genetic pathways were uncovered by Dr. Blackwell and a team of researchers at Duke University Medical Center who compared thousands of genes in hundreds of breast cancer tumors.

"It really is the first demonstration of a biologic reason for why younger women don't do as well when they are diagnosed with breast cancer," says Dr. Blackwell.

The finding also raises the question - could breast cancer in younger women be different enough that it should be considered a completely separate disease?

Probably not says Dr. Ann Partridge, an oncologist at Dana Farber Cancer Institute.

"Breast cancer in general is not just one disease, it's multiple diseases and in younger women the mix is different than in older women," says Dr. Partridge

Researchers are now working on understanding those differences so they can create tailored treatments. That is good news for patents like Corinna. She is looking forward to a day when cancer therapy is no longer part or her routine.

Researchers say the genetic differences they found in the tumors of younger patients are associated with genes that help control a tumor's ability to survive, which would help explain why breast cancers in younger women are often more aggressive and don't respond as well to treatment.

More studies are needed to confirm and better understand the genetic differences.

The research is published in the July 10 issue of the Journal Clinical Oncology.

From the National Cancer Institute: Breast cancer is the leading cause of cancer death in young women ages 15-54. More than 11,100 women under age 40 will be diagnosed with breast cancer this year, and more than 1,100 will die from the disease. The five-year survival rate for young women with breast cancer is 82 percent, which is lower than their post-menopausal counterparts. Young women with breast cancer struggle with many issues that their post-menopausal counterparts don't face, including: the possibility of early menopause, pregnancy after diagnosis, generally more advanced cancers at diagnosis, and higher mortality rates.

Duke researchers looked at samples of nearly 800 breast tumors from women in five countries on three continents, and divided them into age-specific cohorts. The investigators found more than 350 sets of genes that were active only in the tumors from women under age 45. Conversely, tumors arising in women over age 65 did not share these activated gene sets. The breast tumors that arose in younger women shared a common biology, and this discovery was truly remarkable. The genes that regulate things like immune function, oxygen supply and mutations that we know are related to breast cancer, such as BRCA1, were preferentially expressed in the tumors taken from younger women, but when we compared younger women's tumors to older women's tumors, we found those same gene sets were not expressed in the 'older' tumors.

Researchers have already developed compounds that target some of the activated gene expression pathways that the Duke team discovered, and many of these compounds have promise for combating young women's tumors, Dr. Blackwell said. Identifying these characteristic gene expression profiles will be an important part of finding new therapies, she said.

Researchers say many of the gene sets seen in 'younger' tumors distinguished these cancers from 'older' tumors, but the reverse was not true. There was nothing seen in the older women's tumors that set them apart genomically. Researchers say identifying these distinguishing characteristics may be the first step in developing more effective treatments for these younger patients.