Advertisement
 

doctorslounge.com

 
Powered by
Careerbuilder

 

                    Home  |  Forums  |  Humor  |  Advertising  |  Contact
   Ask a Doctor

   News via RSS

   Newsletter

   Oncology

   News

 

 Conferences


   CME

   Forum Archives

   Diseases

   Symptoms

   Labs

   Procedures

   Drugs

   Links
   Specialties

   Cardiology

   Dermatology

   Endocrinology

   Fertility

   Gastroenterology

   Gynecology

   Hematology

   Infections

   Nephrology

   Neurology

   Oncology

   Orthopedics

   Pediatrics

   Pharmacy

   Primary Care

   Psychiatry

   Pulmonology

   Rheumatology

   Surgery

   Urology

   Other Sections

   Membership

   Research Tools

   Medical Tutorials

   Medical Software

 

 Headlines:

 
 

Back to Oncology Articles

Sunday 12th December, 2004

 

The results suggest that almost half of those diagnosed with estrogen-dependent, lymph-node negative breast cancer may not need chemotherapy.

 

tellfrnd.gif (30x26 -- 1330 bytes)send to a friend
 
prntfrnd.gif (30x26 -- 1309 bytes)printer friendly version

  Related
 
  Breast cancer information  
   

A new test can predict both the risk of breast cancer recurrence and may identify women who will benefit most from chemotherapy, according to research supported by the National Cancer Institute (NCI), part of the National Institutes of Health, and performed in collaboration with the National Surgical Adjuvant Breast and Bowel Project (NSABP) and Genomic Health Inc.

These results suggest that almost half of over 50,000 U.S. women diagnosed with estrogen-dependent, lymph-node negative breast cancer* every year are at low risk for recurrence and may not need to go through the discomfort and side effects of chemotherapy.

The test is based on levels of expression (increased or decreased) of a panel of cancer-related genes. This panel is used to predict whether estrogen-dependent breast cancer will come back, according to a study that will be published online in the New England Journal of Medicine on Friday, December 10, 2004. Scientists on this study also will present new results on that day at San Antonio Breast Cancer Symposium indicating that the same test can predict which women benefit most from chemotherapy. Women with low risk of breast cancer recurrence--about half of the women in the recent study--do not appear to derive much benefit from chemotherapy.

The researchers used tissue samples and medical records from women enrolled in clinical trials of the cancer drug tamoxifen, which blocks the effect of estrogen on breast cancer cells. These women had a kind of breast cancer defined as estrogen receptor-positive, lymph node-negative. The technique used is known as reverse-transcriptase-polymerase-chain-reaction (RT-PCR). Each year, over 50,000 women are diagnosed with this kind of breast cancer, which needs estrogen to grow but has not spread to the lymph nodes. Currently, many women with this type of breast cancer in the United States do receive chemotherapy in addition to hormonal therapy.

 

"The test has the potential to change medical practice by sparing thousands of women each year from the harmful short- and long-term side effects associated with chemotherapy."

   

Using samples from 447 patients and a collection of 250 genes in three independent preliminary studies, 16 cancer-related genes were found that worked best. The scientists created a formula that generates a "recurrence score" based on the expression patterns of these genes in a tumor sample. Ranging from 1 to 100, the recurrence score is a measure of the risk that a given cancer will recur.

Prior to this research, analysis of the expression of genes was performed on tumor specimens that were frozen rather than on tissue prepared for routine pathologic evaluation (fixed and embedded). The expression analysis depended on measurement of RNA (the molecule necessary for the translation of a gene into a protein), and RNA is altered when tissues are fixed and embedded. Frozen tissues are generally not readily available in routine practice. Researchers at Genomic Health Inc. developed a method for performing these analyses on tissues embedded in paraffin wax. Their method allows them to use the altered RNA that is found in fixed tissue.

The results published in the New England Journal of Medicine validate the ability of the recurrence score to predict risk of recurrence. Using biopsy tissue and medical records from another NSABP tamoxifen trial, researchers divided 668 women into low, intermediate, and high risk of recurrence groups. Fifty-one percent were in the low risk group (with a score of less than 18); 22 percent were at intermediate risk (recurrence score 18 or higher but less than 31); 27 percent were at high risk (a score of 31 or higher).

These risk group divisions correlated well with the actual rates of recurrence of breast cancer after 10 years. There was a significant difference in recurrence rates between women in the low and high risk groups. In the low risk group, there was a 6.8 percent rate of recurrence at 10 years; in the intermediate and high risk categories these rates were 14.3 percent and 30.5 percent, respectively. Up to a recurrence score of 50, rates of recurrence increased continuously as the recurrence score increased. These trends held across age groups and tumor size.

advertisement.gif (61x7 -- 0 bytes)
 

Are you a doctor or a nurse?

Do you want to join the Doctors Lounge online medical community?

Participate in editorial activities (publish, peer review, edit) and give a helping hand to the largest online community of patients.

Click on the link below to see the requirements:

Doctors Lounge Membership Application


"These results were generated perhaps a decade earlier than would have been possible if the researchers had not had access to biopsy tissue from the NSABP trials," notes Sheila E. Taube, Ph.D., associate director of NCI's Cancer Diagnosis Program.

The same 21-gene test has also been used to predict how beneficial chemotherapy will be for women with estrogen receptor-positive, lymph node-negative breast cancer for women on tamoxifen in NSABP trials. These results will be presented at the San Antonio Breast Cancer Symposium on December 10, 2004.

"NCI staff worked with the company, NSABP and experts from other NCI Cooperative Groups to develop an overall strategy; this plan was fruitful and may lead to providing an important tool for physicians and women to use in considering breast cancer treatment decisions," said Taube.

In the treatment study, women with high recurrence scores, who are representative of about 25 percent of patients with this kind of breast cancer, had a large benefit from chemotherapy in terms of 10 year recurrence-free rates. Women with low recurrence scores, who represent about 50 percent of these patients, derived minimal benefits from chemotherapy. The group under study was not large enough to determine whether chemotherapy is detrimental to the low risk group.

"The test has the potential to change medical practice by sparing thousands of women each year from the harmful short- and long-term side effects associated with chemotherapy," said JoAnne Zujewski, M.D., senior investigator in NCI's Cancer Therapy Evaluation Program.

Source

Paik S, Shak S, Wolmark N, et al. A multigene assay to predict recurrence of tamoxifen-treated, node-negative breast cancer. New England Journal of Medicine, 351(27). December 30, 2004.

 

 advertisement.gif (61x7 -- 0 bytes)

 

 



We subscribe to the HONcode principles of the HON Foundation. Click to verify.
We subscribe to the HONcode principles. Verify here

Privacy Statement | Terms & Conditions | Editorial Board | About us
Copyright 2001-2012 DoctorsLounge. All rights reserved.