Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Childhood cancer survivors' exposure to chemotherapy, radiation does not increase risk of birth defects in their children

13.12.2011
A large, retrospective study shows that children of childhood cancer survivors who received prior treatment involving radiation to testes or ovaries and/or chemotherapy with alkylating agents do not have an increased risk for birth defects compared to children of survivors who did not have such cancer treatment.

The findings provide reassurance that increased risks of birth defects are unlikely for cancer survivors who are concerned about the potential effects of their treatment on their children, and can help guide family planning choices.

"We hope this study will become part of the arsenal of information used by the physicians of childhood cancer survivors if reproductive worries arise," said lead author Lisa Signorello, Sc.D., associate professor of medicine at Vanderbilt University in Nashville, TN, and senior epidemiologist at the International Epidemiology Institute in Rockville, MD. "Childhood cancer survivors face real reproductive concerns, including unknowns related to the effects of therapy. But, hopefully this study will provide some reassurance that their children are unlikely to be at increased risk for genetic defects stemming from their earlier treatment."

According to Signorello, childhood cancer patients frequently receive aggressive, though life-saving, radiation and chemotherapy treatments that can affect their ability to have children. For girls, radiation to the pelvis – and the resulting damage to the uterus – has been associated with a risk for pregnancy outcomes such as miscarriage and preterm birth, and effects on the ovaries can lead to infertility. Radiotherapy and chemotherapy with alkylating agents (e.g., busulphan, cyclophosphamide and dacarbazine) are DNA-damaging treatments, affecting both cancer and healthy cells. Studies to date have not adequately addressed the question of whether genetic damage from a parent's treatment could be passed down to their offspring. Genetic-based birth defects are rare in the general population (about 3 percent), and while previous research results indicated little or no increased risk for birth defects among the offspring of cancer survivors, such studies were relatively small in size and lacked detailed information about radiation and chemotherapy treatments, such as specific radiation doses to the testes and ovaries.

In the current study, investigators used information from the Childhood Cancer Survivor Study, a large retrospective study of treatment and outcomes in more than 20,000 childhood cancer survivors diagnosed between 1970 and 1986. Signorello and her colleagues examined data from 4,699 children of 1,128 men and 1,627 women who were 5-year childhood cancer survivors. The survivors reported their children's health problems through questionnaires, and investigators also examined medical records from survivors and their children, focusing on survivors' history of radiation to the testes or ovaries and chemotherapy with alkylating agents.

Of the survivors, 63 percent (1,736) had received radiation for their cancer as children, and 44 percent of men (496) and 50 percent of women (810) had received chemotherapy with alkylating agents. Overall, 2.7 percent (129) of the survivors' children had at least one birth defect, such as Down syndrome, achondroplasia or cleft lip. Researchers found that 3 percent of children of mothers exposed to radiation or treated with alkylating chemotherapy agents had a genetic birth defect, compared to 3.5 percent of children of mothers who were cancer survivors but did not have such exposures. Only 1.9 percent of children of male cancer survivors who received these DNA-damaging treatments had such birth defects, compared to 1.7 percent of children of male survivors who did not have this type of chemotherapy or radiation. The researchers concluded that children of cancer survivors were not at higher risk for birth defects stemming from parents' exposure to chemotherapy and/or radiation.

The researchers also noted that a strength of their study is the comparison they made to the children of other cancer survivors and not to the children of people randomly sampled from the general population. Signorello said that comparing cancer survivors to individuals in the general population can be difficult because the latter may not be as thorough in reporting health problems of their children, and the children of cancer survivors may be under heightened clinical surveillance and may appear to have higher rates of birth defects as a result. The investigators did, however, find that the overall prevalence of birth defects among the cancer survivors' children was very similar to what has been reported in the general population.

The study is among the largest to examine birth defects in children of childhood cancer survivors, and among the first to evaluate birth defects using medical records to validate both the children's health problems and the parents' radiation and chemotherapy exposures.

"The possibility of birth defects in offspring has been a lingering concern among cancer survivors because it's hard to address," Signorello said. "We know these are rare outcomes, and a large study group was needed to address these questions. It took years to validate the parents' self-reported outcomes, and to assemble and use the medical records of radiation and chemotherapy treatment exposures to allow us to quantify their exposure doses. These are the strongest results to date, adding greater certainty to other studies examining this common concern among survivors of childhood cancer."

The researchers would like to continue to sequence the DNA of families of childhood cancer survivors (survivors and their children) to see if there is any evidence of radiation- or chemical-induced genetic damage, even if the children did not have birth defects. They would also like to combine data from all U.S. and international studies on this topic in order to provide even larger, more definitive results.

ASCO Perspective: ZoAnn Dreyer, MD, ASCO Cancer Communications Committee member and pediatric cancer specialist

"As the proportion of childhood cancer survivors within our population grows, it is clear that a very large number of former patients will be impacted by the results of this study. Cancer survivors and newly diagnosed patients worry about the effect that chemotherapy and radiation therapy may have on their future children. While we as oncologists have felt the risk of congenital abnormalities to be low, we now have concrete data from a very large number of children to support us in our conversations with survivors and newly diagnosed patients. These results will reassure survivors that their previous cancer therapy does not appear to result in an increased risk of birth defects in their future offspring."

Helpful Links from Cancer.Net

Cancer Survivorship: Next Steps for Patients and Their Families
(http://www.cancer.net/patient/Survivorship)
Guide to Childhood Cancer
(http://www.cancer.net/patient/Cancer+Types/Childhood+Cancer)
Childhood Cancer Survivorship
(http://www.cancer.net/patient/Survivorship/Childhood+Cancer+Survivorship)
The Genetics of Cancer
(http://www.cancer.net/patient/All+About+Cancer/Genetics/The+Genetics+of+Cancer)
The Journal of Clinical Oncology is the tri-monthly peer-reviewed journal of the American Society of Clinical Oncology (ASCO), the world's leading professional society representing physicians who treat people with cancer.

ATTRIBUTION TO THE JOURNAL OF CLINICAL ONCOLOGY IS REQUESTED IN ALL NEWS COVERAGE.

Nicole Fernandes | EurekAlert!
Further information:
http://www.asco.org

More articles from Health and Medicine:

nachricht Microgel powder fights infection and helps wounds heal
14.11.2018 | Michigan Technological University

nachricht Spread of deadly eye cancer halted in cells and animals
13.11.2018 | Johns Hopkins Medicine

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: UNH scientists help provide first-ever views of elusive energy explosion

Researchers at the University of New Hampshire have captured a difficult-to-view singular event involving "magnetic reconnection"--the process by which sparse particles and energy around Earth collide producing a quick but mighty explosion--in the Earth's magnetotail, the magnetic environment that trails behind the planet.

Magnetic reconnection has remained a bit of a mystery to scientists. They know it exists and have documented the effects that the energy explosions can...

Im Focus: A Chip with Blood Vessels

Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.

Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...

Im Focus: A Leap Into Quantum Technology

Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.

In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...

Im Focus: Research icebreaker Polarstern begins the Antarctic season

What does it look like below the ice shelf of the calved massive iceberg A68?

On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.

Im Focus: Penn engineers develop ultrathin, ultralight 'nanocardboard'

When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure

Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

“3rd Conference on Laser Polishing – LaP 2018” Attracts International Experts and Users

09.11.2018 | Event News

On the brain’s ability to find the right direction

06.11.2018 | Event News

European Space Talks: Weltraumschrott – eine Gefahr für die Gesellschaft?

23.10.2018 | Event News

 
Latest News

UNH scientists help provide first-ever views of elusive energy explosion

16.11.2018 | Physics and Astronomy

How the gut ‘talks’ to brown fat

16.11.2018 | Life Sciences

Massive impact crater from a kilometer-wide iron meteorite discovered in Greenland

15.11.2018 | Earth Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>