Featured Research

from universities, journals, and other organizations

DNA repair system affects colon cancer recurrence and survival

Date:
May 20, 2011
Source:
Journal of the National Cancer Institute
Summary:
Colorectal cancer patients with defects in mismatch repair -- one of the body's systems for repairing DNA damage -- have lower recurrence rates and better survival rates than patients without such defects, according to a new study.

Colorectal cancer patients with defects in mismatch repair--one of the body's systems for repairing DNA damage--have lower recurrence rates and better survival rates than patients without such defects, according to a study published online May 19th in the Journal of the National Cancer Institute.

About 15% of colorectal cancers are associated with mismatch repair defects. Some defects are caused by the inherited gene mutations found in Lynch syndrome and others occur by chance, or "sporadically." But it has never been clear whether mismatch repair defects are linked to cancer recurrence rates, time-to-recurrence and site of recurrence and whether such defects influence response to chemotherapy.

To explore these questions, Frank A. Sinicrope, M.D., of the Mayo Clinic in Rochester, Minn., and colleagues analyzed data from more than 2,000 clinical trial patients who had been treated after surgery with chemotherapy that included 5-fluorouracil (5-FU), a standard drug used in colorectal cancer. All patients had stage II or III colon cancer.

The patients with defective mismatch repair had lower rates of tumor recurrence, longer remissions, fewer metastases, and better survival rates compared to those without the defects. Both overall survival and disease-free survival were improved.

Whether mismatch repair status influences response to 5-FU therapy has been a subject of some debate. In this study treatment with 5-FU reduced recurrence rates in stage III, regardless of mismatch repair status, but not stage II patients.

The researchers also compared the effects of 5-FU-based therapy in patients thought to have inherited mismatch repair defects versus those whose defects occurred sporadically. They suggest that 5-FU appeared to reduce recurrences only in those with inherited defects.

"In conclusion," they write, "our data demonstrate that patients with defective mismatch repair colon cancers have a statistically significant reduction in their rates of tumor recurrence, a delayed time to recurrence, and better survival rates" than those without the defects. They note that the difference between inherited and sporadic tumors, though a preliminary finding, warrants further study.

In an accompanying editorial, Sabine Tejpar,M.D., Ph.D., of University Hospital Gasthuisberg, Leuven, Belgium, and colleagues note that the influence of mismatch repair defects on patients' prognosis and response to 5-FU has long been a contentious issue. They say that this study, with its large number of samples, provides "valuable information about the prognostic and certainly the predictive role" of mismatch repair defects. The editorialists conclude that it will be important to validate whether patients should have their mismatch repair defects identified as hereditary or sporadic before deciding on chemotherapy with 5-FU.


Story Source:

The above story is based on materials provided by Journal of the National Cancer Institute. Note: Materials may be edited for content and length.


Journal Reference:

  1. Frank A. Sinicrope, Nathan R. Foster, Stephen N. Thibodeau, Silvia Marsoni, Genevieve Monges, Roberto Labianca, Greg Yothers, Carmen Allegra, Malcolm J. Moore, Steven Gallinger and Daniel J. Sargent. DNA Mismatch Repair Status and Colon Cancer Recurrence and Survival in Clinical Trials of 5-Fluorouracil-Based Adjuvant Therapy. JNCI J Natl Cancer Inst, May 19, 2011 DOI: 10.1093/jnci/djr153

Cite This Page:

Journal of the National Cancer Institute. "DNA repair system affects colon cancer recurrence and survival." ScienceDaily. ScienceDaily, 20 May 2011. <www.sciencedaily.com/releases/2011/05/110519161239.htm>.
Journal of the National Cancer Institute. (2011, May 20). DNA repair system affects colon cancer recurrence and survival. ScienceDaily. Retrieved October 21, 2014 from www.sciencedaily.com/releases/2011/05/110519161239.htm
Journal of the National Cancer Institute. "DNA repair system affects colon cancer recurrence and survival." ScienceDaily. www.sciencedaily.com/releases/2011/05/110519161239.htm (accessed October 21, 2014).

Share This



More Health & Medicine News

Tuesday, October 21, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

How Nigeria Beat Its Ebola Outbreak

How Nigeria Beat Its Ebola Outbreak

Newsy (Oct. 20, 2014) The World Health Organization has declared Nigeria free of Ebola. Health experts credit a bit of luck and the government's initial response. Video provided by Newsy
Powered by NewsLook.com
Another Study Suggests Viagra Is Good For The Heart

Another Study Suggests Viagra Is Good For The Heart

Newsy (Oct. 20, 2014) An ingredient in erectile-dysfunction medications such as Viagra could improve heart function. Perhaps not surprising, given Viagra's history. Video provided by Newsy
Powered by NewsLook.com
Ebola Worries End for Dozens on U.S. Watch Lists

Ebola Worries End for Dozens on U.S. Watch Lists

Reuters - US Online Video (Oct. 20, 2014) Forty-three people who had contact with Thomas Eric Duncan, the first person diagnosed with Ebola in the U.S., were cleared overnight of twice-daily monitoring after 21 days of showing no symptoms. Rough Cut (no reporter narration). Video provided by Reuters
Powered by NewsLook.com
CDC Calls for New Ebola Safety Guidelines

CDC Calls for New Ebola Safety Guidelines

AP (Oct. 20, 2014) Centers for Disease Control and Prevention Director Dr. Tom Frieden laid out new guidelines for health care workers when dealing with the deadly Ebola virus including new precautions when taking off personal protective equipment. (Oct. 20) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins